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961Coffee Pests and their Management CCoffee Pests and their Management

Juan f. BarreraEl Colegio de la Frontera Sur, Tapachula, Chiapas, Mexico

The perennial and evergreen nature of the coffee plant (Coffea spp.) favors attack by a number of insects and mites (Table 17, Figs. 73 and 74). All portions of the plants are susceptible to attack, and damage may appear at the seed bed, nursery, plantation, or in the warehouse. Certain pests affect the coffee plant only temporarily, while oth-ers live for several generations on the plant. In some instances, the attack may cause the death of the plant, but in most cases the pests only weaken the plant, reducing yield. When the bean is attacked, quality also may be affected.

Insects constitute the most numerous group of coffee pests; of more than 850 species of insects that feed on coffee in the world, approximately 200 (23.5%) have been reported in the tropical and sub-tropical areas in America. Out of these, hardly thirty species, mostly indigenous, cause losses considered important. The pests and the seriousness of the problems they cause vary from one country to another, and from one area to another. The coffee pest that is considered the most important in tropical America is the coffee berry borer, Hypothenemus hampei (Ferrari) (Coleoptera: Curculionidae: Scolytinae), now cos-mopolitan but originating in Africa. The coffee leaf miner, Leucoptera coffeella Guérin-Méneville (Lepidoptera: Lyonetiidae), and the root mealy-bugs (Pseudococcidae) are causing serious prob-lems in several countries. Bugs of the genus Antestiopsis (Pentatomidae), which are very harm-ful in Africa, have not yet been reported in the American hemisphere.

Most of the insects that are found in coffee plantations are beneficial because they contrib-ute to plant pollination, degrade organic matter, or feed on phytophagous organisms. A study conducted in Mexico showed that parasitic and

predatory organisms, which regulate the popula-tions of many pests, represented 42% of the total of species collected in a coffee plantation. For this reason, it is important to protect and maintain the natural enemies of pests, avoiding the indis-criminate use of chemical pesticides and some agronomic practices that are harmful to natural control. The goal of this section is to describe the biological and ecological characteristics of the main insects and mites of C. arabica L. and C. canephora Pierre ex Froehner, the damage caused by these pests, their natural enemies, and pest management in coffee growing countries of tropical America. The pests to be described are listed in Table 17, which also includes the parts of the plant that are damaged and the development stage of the coffee plant that they damage. The cri-terion applied to include these organisms in the category of “major pests,” was that they were reported in at least one of the manuals on coffee pests that have been published in Brazil, Colom-bia, Costa Rica, Cuba, El Salvador, Guatemala, Honduras, Jamaica, Mexico or Venezuela.

Coffee Berry Borer, Hypothenemus hampei (Ferrari) (Coleoptera: Curculionidae: Scolytinae)

Distribution

This is the most serious insect pest of coffee worldwide. It originated in Africa. In the Americas, it is found in coffee plantations from Mexico to Brazil, including some countries in the Caribbean region such as Cuba, Jamaica, the Dominican Republic and Puerto Rico.

Damage and Economic Importance

Coffee berry borer (Fig. 73) is a direct pest because it causes direct damage to the product to be harvested, the coffee bean. The attacked green, ripe and dry fruits or berries usually show a hole

962 Coffee Pests and their ManagementCCoffee Pests and their Management, Table 17 The most common phytophagous insects and mites of cof-fee in tropical America

Taxon (scientific and common name)

Country where the insect/mite is reported as coffee pest

Developmental stage feeding in/on the plant

Plant parts affected

Acari: Tarsonemidae

Polyphagotarsonemus latus (Banks)

Brazil Nymph, adult Leaves

Acari: Tenuipalpidae

Brevipalpus sp. Brazil, Jamaica, Mexico Nymph, adult Leaves

Acari: Tetranychidae

Olygonychus coffeae (Nietner)

Guatemala, Mexico Nymph, adult Leaves

Olygonychus ilicis (McGregor) Brazil, Guatemala Nymph, adult Leaves

Olygonychus punicae (Hirst) El Salvador Nymph, adult Leaves

Olygonychus yothersi (McGregor)

Colombia, Costa Rica, Venezuela

Nymph, adult Leaves

Coleoptera: Anthribidae

Araecerus fasciculatus (DeGeer)

All coffee growing coun-tries in America

Larva, adult Bean

Coleoptera: Cerambycidae

Plagiohammus maculosus (Bates)

Costa Rica, El Salvador, Guatemala, Honduras, Mexico

Larva Stem, root

Plagiohammus mexicanus Breuning

Mexico Larva Stem, root

Plagiohammus spinipennis (Thomson)

Mexico Larva Stem, root

Coleoptera: Curculionidae

Brachyomus quadrinodosus (Lacordaire)

Venezuela Adult Leaves

Cleistolophus similis Sharp Costa Rica Adult Leaves

Compsus sp. Colombia Adult Leaves

Epicaerus capetillensis Sharp Guatemala, Honduras, Mexico

Adult Leaves

Hypothenemus hampei (Ferrari)

Mexico to Brazil, including Cuba, Jamaica, Dominican Republic, and Puerto Rico

Larva, adult Fruit, bean

Lachnopus buchanani Marshall

Cuba Adult Leaves

Macrostylus boconoensis Bordón

Colombia, Venezuela Adult Leaves

Pantomorus femoratus Sharp Costa Rica Adult Leaves

963Coffee Pests and their Management CCoffee Pests and their Management, Table 17 The most common phytophagous insects and mites of coffee in tropical America (Continued)





Pantomorus godmani Crotch

Brazil Adult Leaves

Steirarrhinus sp. Costa Rica Adult Leaves

Xylosandrus morigerus (Blandford)

Mexico to Brazil Larva, adult Young stems, branches

Coleoptera: Scarabaeidae

Anomala sp. El Salvador Larva Root

Dyscinetus picipes Burmeister Cuba Larva Root

Phyllophaga spp. Widely distributed in coffee plantations in America

Larva Root

Phyllophaga latipes (Bates) El Salvador Larva Root

Phyllophaga menetriesi (Blanchard)

El Salvador Larva Root

Phyllophaga obsoleta (Blanchard)

El Salvador Larva Root

Phyllophaga sanjosecola Saylor

Costa Rica Larva Root

Phyllophaga vicina Moser Costa Rica Larva Root

Hemiptera: Aphididae

Toxoptera auranti (Boyer de Fonscolombe)

Tropical and sub-tropical areas of the Old World. Widely distributed in coffee plantations in America

Nymph, adult Leaves, buds and other tender parts of the plant

Hemiptera: Coccidae

Coccus spp. Mexico Nymph, adult female Aerial part of the plant

Coccus hesperidum L. Guatemala, Mexico Nymph, adult female Aerial part of the plant

Coccus viridis (Green) Brazil, Colombia, Costa Rica, Cuba, Ecuador, El Salvador, Guatemala, Honduras, Jamaica, Mexico, Puerto Rico, Surinam, Venezuela

Nymph, adult female Aerial part of the plant

Parasaissetia sp. Colombia Nymph, adult female Aerial part of the plant

Parasaissetia nigra (Nietner) El Salvador, Guatemala, Puerto Rico, West Indies


Saisettia spp. El Salvador, Mexico Nymph, adult female Aerial part of the plant

964 Coffee Pests and their ManagementCCoffee Pests and their Management, Table 17 The most common phytophagous insects and mites of coffee in tropical America (Continued)





Saisettia coffeae (Walker) Brazil, Costa Rica, Cuba, El Salvador, Guatemala, Honduras, Mexico, Dominican Republic, Venezuela


Saisettia olae (Oliver) Brazil, Cuba, Guatemala, Mexico


Toumeyella sp. Venezuela Nymph, adult female Root

Toumeyella liriodendri (Gmelin)

Guatemala Nymph, adult female Root

Hemiptera: Cerococcidae

Cerococcus catenarius Fonseca

Brazil Nymph, adult female Aerial part of the plant

Hemiptera: Diaspididae

Chrysomphalus sp. Guatemala Nymph, adult female Aerial part of the plant

Chrysomphalus dictyospermi (Morgan)

Guatemala Nymph, adult female Aerial part of the plant

Ischnaspis longirostris (Signoret)

Colombia, Cuba, Guatemala


Lepidoshaphes beckii (Newman)

Venezuela Nymph, adult female Aerial part of the plant

Selenaspidus articulatus (Morgan)

Colombia, Ecuador, Mexico Nymph, adult female Aerial part of the plant

Hemiptera: Margarodidae

Icerya purchasi Maskell Venezuela Nymph, adult female Aerial part of the plant

Hemiptera: Ortheziidae

Insignorthezia insignis Browne Brazil, Colombia Nymph, adult female Aerial part of the plant

Praelongorthezia praelonga (Douglas)

Brazil Nymph, adult female Aerial part of the plant

Hemiptera: Pseudococcidae

Brevicoccus sp. Guatemala Nymph, adult female Root

Ceroputo sp. Costa Rica Nymph, adult female Root

Dysmicoccus sp. Colombia, Ecuador Nymph, adult female Root

Dysmicoccus bispinosus (Beardsley)

Brazil, Guatemala, Hondu-ras, Mexico

Nymph, adult female Root

Dysmicoccus brevipes (Cockerell)

Costa Rica, El Salvador, Guatemala, Honduras, Mexico


965Coffee Pests and their Management CCoffee Pests and their Management, Table 17 The most common phytophagous insects and mites of coffee in tropical America (Continued)





Ferrisia virgata (Cockerell) Brazil, Mexico, West Indies Nymph, adult female Aerial part of the plant

Geococcus sp. Mexico, Venezuela Nymph, adult female Root

Geococcus coffeae Green El Salvador, Guatemala, Honduras, Surinam


Geococcus radicum Green El Salvador Nymph, adult female Root

Neochavesia caldasiae (Balachowsky)

Colombia Nymph, adult female Root

Rhizoecus sp. Mexico, Venezuela Nymph, adult female Root

Rhizoecus andensis Hambleton Colombia Nymph, adult female Root

Rhizoecus coffeae Laing Costa Rica Nymph, adult female Root

Paraputo sp. Guatemala Nymph, adult female Root

Planococcus citri (Risso) Brazil, Colombia, Costa Rica, Cuba, El Salvador, Guatemala, Honduras, Jamaica, Mexico, Puerto Rico

Nymph, adult female Root, aerial part of the plant

Planococcus halli Ezzat & McLonnell


Pseudococcus elisae (Borchsenius)


Pseudococcus longispinus (Targioni-Tozzeti)


Pseudococcus jongispinus Targioni-Tozzetti

Mexico Nymph, adult female Aerial part of the plant

Puto sp. Costa Rica Nymph, adult female Root

Puto antioquensis (Murillo) Guatemala Nymph, adult female Root

Rhizoeccus campestris (Hambleton)


Rhizoeccus caticans (Hambleton)


Rhizoeccus kondonis Kuwana Guatemala Nymph, adult female Root

Rhizoeccus nemoralis Hambleton

El Salvador, Honduras Nymph, adult female Root

Hymenoptera: Formicidae

Acromyrmex spp. Venezuela Adult Leaves

Acromyrmex coronatus (F.) Brazil Adult Leaves

Acromyrmex octospinosus (Wheeler)

Trinidad Adult Leaves

966 Coffee Pests and their ManagementCTaxon (scientific and common name)




Atta spp. Guatemala, Ecuador, Nicaragua, Venezuela

Adult Leaves

Atta cephalotes (L.) Colombia, Costa Rica, Mexico, Surinam, Trinidad

Adult Leaves

Atta fervens Say Mexico Adult Leaves

Atta insularis Guérin-Méneville

Cuba Adult Leaves

Atta laevigata Smith Brazil Adult Leaves

Atta mexicana (Smith) Guatemala, Mexico Adult Leaves

Atta sexdens (L.) Brazil Adult Leaves

Atta sexdens rubropilosa Forel

Brazil Adult Leaves

Lepidoptera: Apateloididae

Olceclostera moresca (Schaus.)

Colombia Larva Leaves

Lepidoptera Arctiidae

Estigmene acrea (Drury) Colombia Larva Leaves

Lepidoptera: Dalceridae

Dalcera abrasa Herrich-Schaeffer

Brazil Larva Leaves

Zadalcera fumata Schaus Brazil Larva Leaves

Lepidoptera: Elachistidae

Stenoma cecropia Meyrick Colombia Larva Leaves

Lepidoptera: Geometridae

Glena sp. Brazil Larva Leaves

Oxydia spp. Colombia Larva Leaves

Oxydia saturniata Guenée Brazil Larva Leaves

Lepidoptera: Limacodidae

Phobetron hipparchia (Cramer)

Brazil, Colombia Larva Leaves

Sibine spp. Colombia Larva Leaves

Lepidoptera: Lyonetiidae

Leucoptera coffeella (Guérin-Méneville)

Widespread wherever coffee is grown in the Neotropical area

Larva Leaves

Lepidoptera: Megalopygidae

Megalopyge lanata (Stoll) Brazil, Colombia Larva Leaves

Podalia sp. Brazil Larva Leaves

Coffee Pests and their Management, Table 17 The most common phytophagous insects and mites of coffee in tropical America (Continued)

967Coffee Pests and their Management CTaxon (scientific and common name)




Lepidoptera: Noctuidae

Agrotis spp. Colombia, Costa Rica, Ecuador, El Salvador

Larva Stems of small plants in germinating seedbeds or recently transplanted plants

Agrotis ipsilon (Hufnagel) Brazil Larva Stems of small plants in germinating seedbeds or recently transplanted plants

Agrotis repleta Walker Venezuela Larva Stems of small plants in germinating seedbeds or recently transplanted plants

Feltia spp. Costa Rica, El Salvador, Venezuela

Larva Stems of small plants in germinating seed-beds or recently transplanted plants

Pseudoplusia includens (Walker)

Honduras Larva Leaves

Spodoptera sp. Colombia, Costa Rica, Ecua-dor, El Salvador

Larva Stems of small plants in germinating seedbeds or recently transplanted plants

Spodoptera eridania (Stoll) Venezuela Larva Stems of small plants in germinating seed-beds or recently transplanted plants

Spodoptera frugiperda (Smith) Costa Rica, Brazil Larva Stems of small plants in germinating seedbeds or recently transplanted plants; leaves

Trichoplusia ni (Hübner) Colombia Larva Leaves

Lepidoptera: Psychidae

Oiketicus geyeri (Berg) Brazil Larva Leaves

Oiketicus kirbyi Lucas

Brazil, Cuba Larva Leaves

Lepidoptera: Saturniidae

Automeris sp. Brazil, Colombia Larva Leaves

Automeris complicata Walker

Brazil Larva Leaves


968 Coffee Pests and their ManagementC

on its apical portion. The hole is located at the center or ring of the berry’s ostiole and the emis-sion of sawdust can be observed through this hole. Its attack reduces the yield and affects the bean quality. Characteristic damage includes the rotting of developing beans as a result of sap-rophytic microorganisms that enter through the hole, the drop of young berries due to attack, and the loss of bean weight due to insect feeding. The borer can cause bean yield losses of 30–35% with 100% of perforated berries at harvest time; nev-ertheless, damage can be greater if harvest is delayed. All the commercial coffee varieties and species are attacked by this insect. However, it shows preference for C. canephora, and its multi-plication is also higher on beans of this coffee species. Recently it was suggested that H. hampei serves as a vector for Aspergillus ochraceus Wilh.,

which produces ochratoxin A, a potent toxin that sometimes contaminates green coffee beans, roasted coffee, and coffee brews, including instant coffee.

Description

The egg is elliptical, crystalline and yellowish toward maturity. Its length varies from 0.52 to 0.69 mm. The larva is white-yellowish, without legs, with a “C”-shaped body and a wide thoracic region. The head is light brown, with visible and forward-extending mandibles. Visible hairs spread over the head and body. Females molt twice and males once. The length of the last lar-val instar is from 1.88 to 2.30 mm. The pre-pupa is similar to the larva, but its color is milky-white,






Automeris coresus Boisduval Brazil Larva Leaves

Automeris illustris Walker Brazil Larva Leaves

Eacles imperialis magnifica (Walker)

Brazil Larva Leaves

Eacles masoni Schaus Ecuador Larva Leaves

Lonomia circunstans (Walker) Brazil Larva Leaves

Orthoptera: Gryllidae

Paroecanthus guatemalae Saussure

Guatemala, Honduras Adult female Stem, branch

Paroecanthus niger Saussure El Salvador, Guatemala Adult female Stem, branch

Orthoptera: Tettigoniidae

Gongrocnemis sp. Guatemala Nymph, adult Leaves, buds, fruit pulp, beans

Idiarthron atrispinum (Stål) Costa Rica, Guatemala Nymph, adult Leaves, buds, fruit pulp, beans

Idiarthron subquadratum Saussure & Pictet

Colombia, Guatemala, El Salvador, Honduras, Mexico

Nymph, adult Leaves, buds, fruit pulp, beans

969Coffee Pests and their Management C

its body is less curved, and it does not feed. The pupa is milky-white and yellowish towards maturity. Many of the adult’s characteristics can be seen in the pupal stage. The pupa varies from

1.84 to 2.00 mm long. The adult is elongated with a cylindrical body slightly arched towards the end of the abdomen. It is about 1.50–1.78 mm long and its body is bright black, although

Coffee Pests and their Management, Figure 73 Some coffee pests: (a) Coffee berry borer, Hypothenemus hampei (Curculionidae) infesting a coffee berry; (b) Damage of coffee leaf by coffee leaf miner, Leucoptera coffeella (Lyonetiidae); (c) Root mealybugs (Pseudococcidae); (d) Scale insects on coffee leaf (Coccidae).

970 Coffee Pests and their ManagementC

Coffee Pests and their Management, Figure 74 Some additional coffee pests: (a) Coffee branch perforat-ed by Xylosandrus morigerus (Curculionidae); (b) Coffee stem attacked by a stem borer, Plagiohammus maculosus (Cerambycidae); (c) Aphids on coffee leaf; (d) Adults of a katydid, Idiarthron subquadratum; (Tettigoiidae) (e) Oviposition by a bush cricket, Paroecanthus (Gryllidae) on the stem of a coffee bush.

971Coffee Pests and their Management Cyellowish when emerging from the pupa. The head is ventrally located and is protected by the pronotum. The antennae are elbowed and clubbed at the ends. Mouthparts are the typical chewing type and the elytra are convex and pos-sess longitudinal grooves that alternate with lon-gitudinal series of bristles. Females have well-developed wings that allow them to fly, while the males’ wings are atrophied. Females are easily differentiated from males because they are larger.

Biology and Ecology

Adult females initiate the infestation. In general, a berry is infested by a single female. If the coffee bean is watery or milky, the insect tends to aban-don it and the bean usually rots. But if the bean consistency is hard enough, the founding female constructs a gallery where she lays the eggs. The eggs are oviposited one by one, forming small groups within the coffee bean. The female lays from 1 to 3 eggs per day during the first 15–20 days; afterwards, the egg laying diminishes grad-ually. Both the founding female and the larvae build tunnels in the bean, where they also feed. Pupation takes place within the coffee bean where the larva hatched. The duration of the bio-logical cycle, from egg to adult, varies according to the temperature: 21 days at 27°C, 32 days at 22°C and 63 days at 19.2°C. As the first adult off-spring appear, the population inside an infested bean typically consists of 25–30 individuals in all stages of development, of which there are approximately 10 females for each male. Mating is conducted between siblings inside the bean. The mated females leave the bean where they developed to look for another where they will oviposit. Several generations occur while berries are available. After coffee harvest, the borer continues to reproduce in the non-harvested berries located on the plant and on the ground. In locations with low rainfall, where there is a clearly defined period between harvests, the

adults find refuge in the black, dry berries. Adult females emerge massively from these old berries with first rainfall, initiating the infestation by attacking berries from the earliest flowerings of the new harvest.

Natural Enemies

Coffee berry borer is attacked by several natural enemies. Four parasitoid species from Africa are the best known: Prorops nasuta Waterston (from Cameroon, Ivory Coast, Zaire, Kenya, Tanzania, Togo, Uganda) and Cephalonomia stephanoderis Betrem (Ivory Coast, Togo) (both Hymenoptera: Bethylidae), and two solitary ectoparasitoids of the larva, pre-pupa and pupa, Heterospillus coffei-cola Schimideknecht (Hymenoptera: Braconidae) (Cameroon, Zaire, Kenya, Tanzania, Uganda) (a free-living wasp that deposits a single egg near a borer’s egg cluster in a recently attacked berry) and Phymastichus coffea LaSalle (Hymenoptera: Eulophidae) (Togo, Kenya) (a gregarious endop-arasitoid of H. hampei adults which parasitizes the borer during the berry perforation). Other parasitoids that have been reported attacking H. hampei include Aphanogmus dictyna (Water-ston) (Hymenoptera: Ceraphronidae) (Uganda), Sclerodermus cadavericus Benoit (Hymenoptera: Benthylidae) (Uganda, Zaire, Kenya), Cephalono-mia hyalinipennis Ashmead (Mexico) and Cryp-toxilos sp. (Hymenoptera: Braconidae) (Colombia). In Brazil and Colombia, there are reports of an undescribed species of Cephalonomia parasitizing H. hampei.

Some of the predators that have been recorded include Dindymus rubiginosus (F.) (Hemiptera: Pyrrhocoridae) (Indonesia), Calliodes, Scoloposcelis (Hemiptera: Anthocoridae) (Colombia), and Lep-tophloeus sp. near punctatus Lefkovich (Coleoptera: Laemophloeidae) (Togo, Ivory Coast). However, most of the predators of H. hampei reported from around the world (most of them anecdotal records) have been ants (Hymenoptera: Formici-dae), including Azteca instabilis (F. Smith),

972 Coffee Pests and their ManagementC Crematogaster curvispinosa Mayr, C. torosa Mayr, Dolichoderus bituberculatus Mayr, Pheidole radoszkowskii Mayr, and Solenopsis geminata (F.). Unknown species of Azteca, Brachymyrmex, Paratrechina, Pheidole, Prenolepis and Wasmannia have been recorded as well.

Several entomopathogenic fungi attack the cof-fee berry borer, but Beauveria bassiana (Balsamo) Vuillemin is the most common species infecting H. hampei adults under natural conditions. Other fungi recorded infecting H. hampei are Fusarium oxyspo-rum Schlechtend, F. avenaceum (Fr.) Sacc., Hirsutella eleutheratorum (Nex ex Gray) Petch., Metarhizium anisopliae (Metschnikoff) Sorokin, Nomuraea rileyi (Farlow) Samson, Paecilomyces amoenoroseus (Hen-nings) Samson, P. farinosus (Holm. ex S.F. Gray), P. fumosoroseus (Wize) Brown & Smith, P. javanicus (Friederichs & Bally) Brown & Smith, P. lilacinus (Thom.) Samson, and Verticillium lecanii (Zimmer-man). Some of these fungi, such as M. anisopliae and P. lilacinus, have been isolated from H. hampei-infested berries collected from the soil.

Metaparasitylenchus hypothenemi Poinar (Tylenchida: Allantonematidae), an entomopatho-genic nematode attacking H. hampei adults, has been reported in Mexico and appears to have a wide distribution in coffee plantation in Mexico and Central America

This nematode cause sterility in female bor-ers. The natural parasitism by an undescribed species of Panagrolaimus (Rhabditida: Panagro-laimidae) has been reported in H. hampei in India and Mexico. M. hypothenemi and Panagrolaimus sp. were found infecting the same H. hampei adults in Mexico. Species from Heterorhabditidae and Steinernematidae (Rhabditida) are able to infect H. hampei in the laboratory, but this has not been observed in the field.

In Colombia, infections in the coffee berry borer caused by bacteria such as Bacillus sp. and Serratia sp. were observed. Also, infections of proteobacterium Wolbachia in H. hampei adults have been reported from samples around the world. The microsporidian Mattesia sp. was observed in a population of laboratory-reared insects.

Management

An integrated pest management strategy is used against the coffee berry borer. The principal tactics are cultural control, biological control, use of traps baited with attractants, and chemical control with synthetic insecticides. Sampling infested berries is used for pest control decision-making.

Sampling Infested Berries

The proportion of infested berries is calculated based on the following sampling protocol: in an area of 1–5 ha, 20 uniformly distributed sites are selected; at each site five coffee plants in a row are selected; 20 berries of each coffee plant are exam-ined (without tearing them off), and the number of perforated berries is recorded.

Cultural Control

There are a number of cultural practices that may be used to minimize damage by borers. The ber-ries left on the plant before maturity and on the ground after harvest are collected and boiled for 5 min to eliminate the borers in them. This practice is also called “manual control” or “rere.” Weeds are controlled after the harvest in order to facilitate the collection of berries from the ground and to increase the mortality of H. hampei by dehydra-tion of the berries. The coffee and shade plants are pruned to create less favorable environmental conditions for multiplication of the borer. Coffee plant density is decreased because high sowing densities favor infestation. The coffee plants are fertilized so that they have more uniform flower-ings. Varieties with the same fruiting pattern are used because the early flowering varieties are an infestation source for late flowering varieties; however, coffee varieties or species which flower earlier or later than the main variety can be used as “trap crops,” if managed properly. The harvest is conducted as the fruits ripen.

973Coffee Pests and their Management CBiological Control

The natural enemies most often used against the borer in tropical America have been the par-asitoids C. stephanoderis, P. nasuta and P. coffea, and the entomopathogenic fungus B. bassiana. These three parasitoids were introduced to tropical America from Africa. They are estab-lished in most of the countries where they have been released. Nevertheless, classical biological control with these African parasitoids has not been sufficient to reduce the borer population below the economic injury level. Yearly inocula-tive and inundative releases of parasitoids have been used with better results. However, inunda-tive releases are expensive because mass rearing methods and facilities have not been developed for area-wide releases. Parasitoids are produced for inoculative releases in laboratories where the borer is reared mostly in parchment coffee (35% humidity) for use in rearing the parasi-toids. A rearing system for H. hampei in an arti-ficial diet has been developed; however, its application for mass production of parasitoids is not fully employed. An alternative and less intensive rearing system to produce parasitoids for inoculative releases is production of the par-asitoids in rural areas, also known as “parasitoid rural rearing.” In this system, the coffee growers rear the parasitoids at their farms or communi-ties. Such rearing is conducted using coffee berries infested by the borer in the field. Regard-less of the rearing method used, annual releases of parasitoids are needed to manage the borer population.

The use of B. bassiana for borer control is more developed than is the use of parasitoids. Its success has resulted from the relatively easy propagation, formulation and application of this fungus. Strains of B. bassiana are commonly collected for mass production from infected H. hampei females in the field. Rice grains are used as the propagation substrate for this entomopatho-gen. The fungus requires high relative humidity for germination of the spores and it is very susceptible

to sunlight. Early in the morning is the most effective time to apply it in the field, when the borer is starting to penetrate the coffee berry.

Insect Traps

Traps are used for monitoring and control of the coffee berry borer. They are made using 2 L plastic bottles into which one or more windows have been cut to allow the entry of flying females. Bor-ers are attracted by a mixture of methanol and ethanol (1:1 or 3:1) and they are caught and drowned in the water placed at the bottom of the trap. Typically, 16–25 traps are deployed per hect-are. Each trap is suspended from a branch of a coffee plant at 1.2–1.5 m above the ground. Borers captured are removed from the traps and counted weekly. The best time to use the traps for H. ham-pei control is after the harvest, during the massive emergence of females from old berries. Better results for suppression of insect infestation in the next harvest can be obtained by combining the use of traps with strict sanitation.

Chemical Control

There are several chemical insecticides used for borer control, among which endosulfan is out-standing for its ability to cause high mortality of H. hampei. However, this organochlorine insecti-cide is being seriously questioned for negative side effects (it is highly toxic to fish and bees, and it causes secondary pest outbreaks by eliminating the natural enemies); borer resistance (appar-ently this pest is not resistant to endosulfan in tropical America; nevertheless, there is concern about the development of resistance, as in the case of New Caledonia); and sanctions in the international market due to the possible presence of residues in the coffee bean. The insecticide should only be used if the borer population reaches the economic threshold. The best time for spraying is when the adult borer starts

974 Coffee Pests and their ManagementC penetrating the fruit, at the so-called semi-con-sistency stage of development (about 20% dry weight in the bean). This period varies, according to the temperature, from 90 to 140 days after the main flowering. Formerly, treatments were throughout the plantation, but now sprays are directed only at infested areas.

Coffee Leaf Miner, Leucoptera coffeella (Guérin-Méneville) (Lepidoptera: Lyonetiidae)

Distribution

This species is found in the Neotropics: Mexico, Central America, South America and the Caribbean region. It is widespread wherever coffee is grown.


In some areas of tropical America, the coffee leaf miner is considered to be the principal insect pest of coffee; certainly this is the case in some coffee-growing areas in Brazil. Leaves are the only plant organs damaged by this insect. The damage is caused by the larva. Four larvae per leaf may cause leaf drop. The affected leaves show irregular light-brown spots. If the damaged sur-face of the leaf is rubbed, the leaf separates into two layers and between them is found a small white worm, from 2 to 5 mm in size. The coffee leaf miner lesions may be confused with the symptoms of Anthracnose (Colletotrichum sp.), but in the latter case the leaf layers do not sepa-rate when rubbed. Four months after flowering, a reduction in the rate of growth of the coffee ber-ries and an increase in leaf production take place; this allows the plant to compensate for the dam-age caused by the miner. But when the fruit growth starts again, if there is more than one leaf miner lesion per leaf it will result in economic damage. The damage increases if simultaneously the plant is under drought stress. Attack of coffee

by leaf miner can cause severe defoliation. In Ecuador, defoliation between 70 and 90% has been reported on C. arabica and from 30 to 40% on C. canephora. The lack of leaves on the plant reduces the photosynthetic activity, and conse-quently the availability of nutrients for the fruits. In Brazil, when 94–95% of the leaves were mined, a reduction in yield between 68–80% has been observed.

Description

The egg is oval, translucent yellow and similar to a flattened volcano in profile. It is 0.28 mm long, 0.18 mm wide, and 0.08 mm tall. The larva has a dors-oventrally flattened body with a more pro-nounced flattening of the head and the first thoracic segment. The true legs are found on the 1st, 2nd and 3rd thoracic segments but four pairs of prolegs occur on the 6th, 7th, 8th and 13th abdominal segments. It has four larval instars. The larva attains a length of 4.5 mm. The pupa is white in the initial stage and ochre towards maturity, except for the dorsal portion, which remains white. The pupa is covered by a white cocoon which resembles an elongated “H” or “X.” The adult is a small moth between 2.0 and 3.0 mm long with its body covered by silvery scales. The antennae are long and thin. The front wings possess a gray oval point distally, surrounded by a black line and edged by a yellow stripe that extends along the margin. Males tend to be slightly smaller than females.

Biology and Ecology

The female usually lays its eggs irregularly on the upper surface of the darkest, most mature leaves, particularly on the middle and lower parts of the coffee plant. Eggs are laid individually or in small clusters of up to seven eggs, with a total fecundity that varies between 30 and 80 eggs. Upon hatch-ing, the larva makes a semi-circular cut at its base

975Coffee Pests and their Management Cand penetrates rapidly into the leaf, where it moves about, mining the palisade parenchyma tissue. When ready to pupate, the fully developed larva leaves the gallery very early in the morning, making a semi-circular cut on the face of the leaf, through which it slips down by a silk thread which it secretes from the mouth. Cocoon for-mation and pupation take place on the lower face of the coffee leaf, often on a curvature of the leaf or close to a protruding vein. The duration of the life cycle, from egg to adult, lasts between 25 and 75 days, depending on the temperature. Several generations occur annually, particularly in coffee plantations with full sunlight or only lightly shaded. The abundance of L. coffeella is signifi-cantly affected by the onset of rainfall, and by natural enemies, which are very numerous after the end of the dry season.

Natural Enemies

The coffee leaf miner is attacked by a large number of parasitoids; predators and some insect pathogens have also been recorded. More than 20 morphospecies of parasitoids wasps (Hymenoptera) have been reported in tropical America. Eulophidae are the most common par-asitoids of L. coffeella; this group is largely unknown because keys for neotropical species do not exist. In Mexico, Neochrysocharis was the genus with the greater number of morphospe-cies, and also the one that was collected most fre-quently. It was followed, in order of abundance, by Pnigalio, Closterocerus, and Zagrammosoma. Of two braconids collected in Mexico, Stiropius letifer (Mann) was the most abundant and most widely distributed. Wasps (Vespidae) are the most important predators of coffee leaf miner in Bra-zil, but in Mexico, the most important predators are ants (Formicidae). The bacteria Pseudomonas aeruginosa (Schroeter) Migula and Erwinia her-bicola (Löhnis) Dye, and the fungus Cladospo-rium sp., have been reported infecting L. coffeella.

Management

There are several useful approaches to manage-ment of coffee leaf miner. population. Sampling is recommended prior to initiating chemical control.

Sampling Damaged Leaves

The recommended sampling protocol follows: sampling is initiated when the coffee flowers, and is conducted monthly until the berries stop grow-ing. The coffee plantation to be sampled is divided into areas not larger than one hectare. The sam-pling is conducted by selecting a zigzag path across the coffee plantation and by selecting 12 coffee plants at random. From each coffee plant, 25 leaves are selected at random, and the number of leaves with mines is recorded. The first two pairs of leaves at the tip of the branches are not sampled.

Cultural Control

The shade canopy of coffee plantation should not be trimmed immediately after harvest; it should be thinned only when the onset of the rainy sea-son is imminent. Adequate soil fertilization is important. Thick mulch coverage of the soil should be maintained. High coffee plant densities should be avoided. The coffee plant should be pruned to stimulate vigorous growth. Damaged leaves should be collected and placed in contain-ers that allow the escape of parasitoids but not of the coffee leaf miner.

Biological Control

The introduction of natural enemies into new areas has not been widely explored. The most important action conducted so far has been to protect the already existing natural enemies by

976 Coffee Pests and their ManagementCavoiding the use of broad-spectrum, residual contact insecticides. The natural control exerted by the coffee leaf miner’s natural enemies varies from 2 to 70%; however, in most cases it is unnec-essary to resort to the use of chemical control. Regrettably, the use of chemical insecticides may eliminate a large portion of the beneficial organ-isms, causing pest resurgence and making it dif-ficult to implement control. In certain countries like Honduras, high and recurring L. coffeella infestations have diminished significantly when the use of chemical control is not applied for sev-eral years and the beneficial fauna is restored. This supports the idea that coffee leaf miner con-trol should not be based on use of insecticides in order to avoid disrupting the actions of parasi-toids and predators.

Chemical Control

Numerous chemical insecticides can be used for suppression of L. coffeella and protection of foli-age. These products include both organophos-phate and pyrethroid insecticides. They are inexpensive and can be applied at the same time with other agrochemicals, but they are highly toxic and they are more likely to cause ecological disturbances. Organophosphorates are often applied twice at an interval of 30–45 days, with an additional application in cases of severe attack. In the case of pyrethroids, one or two applications at an interval of 45–60 days are rec-ommended. The application of granular insecti-cides with systemic action to the soil is also recommended in cases where it is difficult to apply foliar sprays. Soil applications interfere much less with the natural enemies of the coffee leaf miner, and this approach can be used to con-trol pests and soil diseases simultaneously. Gran-ular insecticides should be shallowly buried at the drip line of the plant once a year during the rainy season. Where this type of product is used, it is recommended that harvest occur 90 days after application.

Root Mealybugs (Hemiptera: Pseodococcidae)

Distribution

Root mealybugs are found in Neotropical coun-tries where coffee is grown. The principal root mealybugs affecting coffee plants in tropical America are shown in Table 17.


These insects attack the coffee plant roots and some species also affect the foliage. The foliage of attacked coffee plants appears withered, the color of the leaves fade, and they have copper, brown or necrotic edges. Additionally, total or partial leaf drop may occur. These symptoms are more evident during the dry season. In case of serious attacks by Dysmi-coccus bispinosus (Beardly), a thick, cork-like, dark crust covers the main and secondary roots; the attacked roots lose their absorbent root hairs. Heav-ily attacked plants perish. Infestation appears to be associated with ants (Formicidae). The symptoms may be confused with the symptoms of fungal diseases and with physiological plant problems. In the case of Neorhizoeccus coffeae (Laing) and D. brevipes (Ckll.) infestations, the branches turn whitish and the affected root seems to be covered with flour, the crust separates easily, and consider-able deteriorated tissue appears. The attacked plants have little anchorage and are easily dislodged.

Root mealybugs have become important coffee pests in some areas of tropical America during the last 20 years. In Guatemala, the most harmful species is D. bispinosus; in Costa Rica, N. coffeae and D. brevi-pes; in El Salvador, D. brevipes, Rhizoeccus nemoralis Ham. and Geococcus coffeae Green; and in Colombia, Chavesia caldasiae (Balachowsky). At some coffee plantations in Colombia, Planococcus citri (Risso) has also appeared as a pest, causing up to 30% yield loss in the attacked trees. Other forms of damage caused by root mealybugs include excessive extraction of potassium, destruction of the absorbent root hairs,

977Coffee Pests and their Management Cdevelopment of small rotting areas which tend to atrophy, and enhanced entry of plant pathogens. This damage creates a general condition of weakness, slow growth and plant death in many cases.

Dysmicoccus brevipes weakens the coffee plants but it rarely kills them. In Costa Rica, plants with more than 20 mealybugs per liter of soil are more susceptible to infection by the fungus Cercospora coffeicola Berk & Cooke. Damage is more apparent on nutrient-deficient soils, and where weeds are abundant. Plants in seed beds and tree nurseries are also attacked. The varieties of C. arabica grown in Central America (e.g., Caturra, Catuaí, Bourbon) are susceptible to the mealybug attack, while tolerance has been observed on C. canephora, C. dewevrei De Wild. & Durand, and C. excelsa Chev.

Description

Mealybug eggs are small (0.5 mm). The nymphs are oval, slightly swollen, usually white, yellow or pink-colored, and covered by a white waxy-mealy dust with waxy filaments projecting laterally. The female nymphs molt three times, and the males, contrary to the females, form a waxy cocoon in the third instar, where they pupate. The adult females have no wings and they are similar to the nymphs but larger. Smaller species, such as Geococcus and Rhizoecus, are from 1.5 to 2.0 mm long and the larger ones, such as Dysmicoccus and Pseudococcus, are from 2.5 to 5.0 mm long. Males are white, fragile-looking, smaller than the females, and they possess a pair of wings and a pair of terminal filaments.

Biology and Ecology

Mealybugs generally live attached to the coffee root, forming numerous colonies. Their reproduction may be sexual or parthenogenetic (partial or total). Eggs are laid in groups and covered by a layer of cotton-like wax or by an egg sac of crystalline wax filaments. A single female may deposit 300–600 eggs.

Other species, such as Pseudococcus adonidum (L.) are oviparous. Females die shortly after the eggs hatch. Upon eclosion, the small nymphs start look-ing for an appropriate place to settle on the plant root; at the selected site, they insert their mouthparts, and feed by suctioning the sap from the root. Some of them settle down permanently on a site until they reach maturity, and others may change their feeding site by moving short distances. Depending on the type of soil, the humidity, aeration and age of the coffee plant, they usually place themselves between 10 and 60 cm under the soil surface, their popula-tion diminishing as the soil depth increases. Differ-ent species prefer different parts of the root. For example, D. brevipes and R. nemoralis prefer the main and the lateral roots, while G. coffeae attacks the absorbent roots; the smaller species attack the whole root system near the soil surface.

As they feed and develop, the nymphs and adults excrete their characteristic waxy cover and form compact colonies. Mealybugs excrete sugary substances (honeydew), which supports the growth of fungi (i.e., Bornetina), which contribute to for-mation of the thick, cork-like, dark crust covering and sheltering the mealybug colony; a succession of crusts give a knotty appearance to the root. The sug-ary substances also attract certain ant species, which live in a symbiotic association (trophobiosis) with the mealybugs. In exchange for the sugary foodstuff, the ants give them protection and transportation from one root to another and from one plant to another. The ants that associate with mealybugs in South America and in some of the Caribbean Islands are in the genus Acropyga. In Colombia, the Hope ant (A. robae Donisthorpe) and the Amagá ant (A. fuhrmanni Forel) are associated with N. cof-feae and C. caldasiae, respectively. In Guatemala, D. bispinosus seems to be associated with the presence of the ant Solenopsis geminata (F.). P. citri does not produce large quantities of sugary excretions when it lives on the plant roots, and is not attractive to ants. In certain cases, the mealybugs have lived for more than a year in the absence of ants.

The life cycle, from egg to adult, requires from 30 to 120 days, according to the species and the

978 Coffee Pests and their ManagementCtemperature. Five generations develop per year in the case of D. bispinosus. Root mealybugs develop better during the rainy season, particularly in low or medium altitude plantations in Central Amer-ica. Other conditions that favor their development are sandy, acid pH, and medium moisture soils. In Colombia, the damage caused by Rhizoecus sp. seems to increase in old, poorly fertilized planta-tions, and in Guatemala D. bispinosus is found most frequently in 1–5 year-old plantations. Mealybugs are polyphagous, also attacking other plants such as shade trees (Inga spp.), cassava (Manihot escu-lenta Crantz), sugarcane (Saccharum), banana trees (Musa), lemon trees (Citrus) and some herbs that grow on the coffee plantation. In Costa Rica, Anred-era ramosa (Moq.) Eliasson is an alternate host of D. brevipes; in El Salvador, D. bispinosus has been found associated with Lantana camara L.

Natural Enemies

In general, the literature on coffee mealybugs in tropical America does not make reference to their natural enemies. In Cuba, Coccidoxenoides peregrinus (Timberlake) (Hymenoptera: Encyrtidae) is cited as a solitary, primary endoparasite of the pseudo-coccid complex in coffee. Other natural enemies of mealybugs reported in Cuba are Diadiplosis cocci Felton (Diptera: Cecidomyiidae), Leptomastix dactylopii Howard (Hymenoptera: Encyrtidae) and Signiphora sp. (Hymenoptera: Signiphoridae).

Management

There are management options for mealybugs, but insecticides are normally used once pest popula-tions develop.

Sampling

Sampling should preferably be conducted on young coffee plantations (up to 6 years old). Plants near

ant nests should be examined critically; from 15 to 20 plants/ha should be checked, paying more atten-tion to those that are close to the ant nests and/or possess yellow leaves. The surrounding shade trees and bushes should also be checked. The plants are checked by moving the stems in all directions in order to gain visibility of the base of the roots.

Cultural Control

Mealybugs should not be present in the seed bed and tree nursery. The limits of any infestation sites should be determined and marked. Adequate fertilization should be provided, including addition of organic matter to the soil. Physical conditions of the soil should be improved in order to avoid floods. Planting coffee trees on land previously supporting plants that are highly susceptible to mealybugs (e.g., cassava, sugarcane) should be avoided. Alternate host plants should be eliminated from the plantation. Severely dam-aged plants should be removed and burned.

Biological Control

This is practically unexplored in the coffee grow-ing countries of tropical America.

Plant Resistance to Insects

In Guatemala, some research has been conducted which supports the use of plants grafted on resis-tant rootstocks of C. canephora (genotypes 3757, 3754, 3751, 3581, 3752 and 3756) and C. dewevrei.

Chemical Control

Systemic organophosphorate and carbamate insec-ticides produce good results, although they are expensive. The presence of mealybugs in seed beds or on plants younger than 1 year old is sufficient

979Coffee Pests and their Management Cjustification for insecticide application. On planta-tions older than 3 years, insecticide application is made if more than 1.6 colonies per plant, on average, are found. In no case should the damage be allowed to exceed 25% of the absorbent roots. Insecticides are applied on the drip line of the plant if the dam-age is on the small roots. If the damage is on the main root a funnel-shaped hole should be made around the tree trunk, the insecticide should be poured in and the hole should be covered again with soil, adding also a layer of dead leaves. Application of granular insecticides is made at the beginning of the rainy season or 3 months before starting the harvest.

Scale Insects, Mealybugs and Related Foliage Pests (Hemiptera)

Distribution

Different scale insects, mealybugs and related foliage pests live on the coffee plant. The geo-graphic distribution of some is restricted to a few countries of tropical America, whereas others are distributed more widely. Some are reported attacking the coffee plant only in South America, others only in Central America or the Caribbean (Table 17).


Scale insects, mealybugs and related species attack the aerial part of the coffee plant and, in some spe-cies, also the root (e.g., Planococcus citri [Risso]). The leaves, fruit, branches and young tissues of the aerial part of the attacked coffee plant often support colonies or groups of circular, oval or elon-gated scales, which may be flattened or swollen, with a soft or hard consistency. In other cases, colo-nies of insects have a soft body covered with white, cotton-like filaments. These insects cause damage by removing large quantities of sap, which causes plant malnutrition. Also, sticky honeydew and blackish molds can be found covering the foliage.

When Capnodium (sooty mold) and Meliola (black mildew) fungi grow on the honeydew excreted by the scales, they interfere with photosynthesis. Ants are present where scale insects are feeding.

In cases of severe attack, a dirty appearance on the plant, general weakening, growth delay, yel-lowing and drop of foliage and fruit are observed. With the articulated scale, Selenaspidus articulatus (Morgan), old attacks may be recognized because the site where the scales were located turns yellow or discolored, resembling infection by the coffee rust fungus (Hemileia vastatrix Berk. and Br.). Some species, such as the green scale, Coccus viridis (Green), are considered to be quite impor-tant to coffee production, though some attack a number of different cultivated plants. Severe infes-tations of C. viridis may kill young tree nursery plants. The incidence of these pests is highest on coffee plantations lacking adequate shading.

Pest Description

The following cases are presented as examples: C. viridis – adult females are motionless, oval, some-times asymmetric, very flat and pale yellow. They have some black spots centrally, and they tend to be soft and elastic. They are about 2.2 mm wide and 4.0 mm long. The presence of males is very rare. Saisettia coffeae (Walker) – adult females are motionless, almost spherically shaped and dark brown. They are 2.0–3.5 mm in diameter. The males are winged. P. citri – adult females are mobile, oval, pale yellow or dark orange, with very clear segments on the body, and 4.0 mm in size. They are covered with a dusty white glandular secretion except for a longitudinal stripe dorsally. They have filaments lat-erally. Males are smaller (1.0 mm), violet to yellow in color, and they have well-developed wings.

Biology and Ecology

The biology of these insects varies among spe-cies and can be quite complex. The first instar

980 Coffee Pests and their ManagementChas legs and antennae and is very active. To feed, the insects attach and insert their mouthparts. After the first molt, they generally lose their legs and antennae and the insect becomes sessile. By then, it begins to secrete a waxy, scale-shaped layer that covers the body. In the case of scales of the family Diaspididae, this layer of scale is almost always separated from the insect’s body. Adult females remain under this cover and they produce their eggs or directly give birth to the nymphs therein. The location on the plant, and the age of the plant they prefer to attack, depends on the species of scale: C. viridis is commonly located along the leaf veins, on the back of the leaves, on young buds and on seed bed coffee fruits of nursery plants; S. articulatus is found mainly on the leaves and fruits of production plants; the round scale, Parasaissetia sp., mostly attacks the stems and branches of coffee plants younger than 1 year; the black scale, Ischnaspis longirostris (Signoret), infests the leaves, branches and fruits of old, poorly attended coffee planta-tions; Cerococcus catenarius Fonseca gathers in the form of a line or chain along the trunks and branches; P. citri attacks new branches, leaves, flower buds, fruit peduncles and fruits; Orthezia spp. attack branches, leaves and fruits, mostly of robusta coffee in Brazil. The males develop very much like the females except that in the last stage, before transforming into adults, they go through a pupal stage; the wings develop exter-nally over the pupa. Most of the scales reproduce parthenogenetically. Some species are oviparous (S. coffeae, S. olae [Oliver]) and others are vivipa-rous (Coccus hesperidum L.). The total number of eggs produced per female varies among the species; for example: C. viridis, between 50 and 600 eggs; Orthezia praelonga Douglas, more than 200 eggs; C. catenarius, about 900; S. coffeae can lay up to 1,600 eggs. The complete life cycle, from egg to adult, lasts between 40 and 60 days. The scale insects are more abundant during the dry season and at the onset of the rainy period. Hard rains and natural enemies are important factors in the mortality of these pests.

Natural Enemies

These insects are susceptible to a large number of parasites, predators and pathogens as natural enemies.

Management

Sampling

During the dry season, inspections should be con-ducted to check for the presence of scales and related species in the coffee plantation, as well as on other plants cultivated nearby or at the same time.

Cultural Control

The nursery shading should be reinforced during the dry season. Affected plants should not be transplanted. Weeds should be suppressed. The pests should be kept under control on host plants existing in or near the coffee plantations. Sanitary pruning should be performed to eliminate (by burning) old and unproductive branches infested by the pests.

Biological Control

Natural enemies should be protected and pre-served, using insecticide only if necessary.

Chemical Control

Chemical control is directed only at infested plants, after checking to determine that the scale colonies are alive. For better control, mineral oil is added to the insecticide solution, with applications made every 15 days until the problem is corrected. The oil should not be used during flowering or during sunny periods of the day. During the rainy season, granulated insecticides may be used.

981Coffee Pests and their Management CCutworms and Armyworms (Lepidoptera: Noctuidae)

Distribution

These insects are widely distributed in the coffee plantations of tropical America (Table 17).


Cutworms and armyworms constitute an economi-cally important pest for many crops. Damage is caused during the night by the larval stage. The larvae attack the stems of small coffee plants in ger-minating beds, seedbeds or plant nurseries, and recently transplanted plants. On seed beds and plant nurseries, plant damage typically takes the form of plants cut at the soil level or slightly above, or withered plants. In the case of recently transplanted coffee plants, defoliated and sometimes dead coffee plants can be observed. Spodoptera frugiperda (Smith) larvae feed on the stem, causing withering and finally death of the small plants during the first year of their lives. In other cases, the stem breaks at the site of the ring formed by the larval feeding. When the infestation is severe, many plants are killed and re-sowings are needed, which increases the cof-fee plantation set-up costs. Damage is more frequent in plantations that are close to fields where corn, beans, vegetables, cassava or pasture are grown.

Pest Description

The following species are presented as examples: S. frugiperda – the larvae have a well-contrasted, inverted “Y” on the head; neonate larvae are white with a black head, but as they grow they turn dark. Large worms are light brown to dark green in color and they are about 4.0 cm long. Agrotis ipsilon (Huf-nagel) – small larvae are brown with paler back marks, and large ones, which may be as be as large as 4.0–5.0 cm, are shiny black-gray in color, with a pale gray line on the back and black tubercles on each of the segments.

Biology and Ecology

Adults are moths that are active at night, laying their eggs individually (A. ipsilon) or in groups (S. frugiperda). During the first two larval stages, they feed on leaves that are at soil level, and in the last three they act as cutting worms. During the day, they remain hidden in the soil. In some species, such as A. ipsilon, the larvae coil up when disturbed. Larvae pupate in the soil.

Natural Enemies

There are many natural enemies (parasitoids, predators and pathogens) of these pests. In Ecua-dor, the larval parasitoids Bonetia sp. (Diptera: Tachinidae) and Chelonus sp. (Hymenoptera: Braconidae) and the predatory ground beetle Calosoma sp. (Coleoptera: Carabidae), are cited.

Management

Sampling

Night-time inspection of seedbeds and the young plantations should be made to detect initial infestations.

Cultural Control

Seedbeds or plant nurseries should be kept clean of weeds and dead leaves, since the larvae seek shelter there.

Mechanical Control

Larvae should be eliminated by hand during the night-time inspections. Heavy watering should be applied to get the larvae out of their hiding places, followed by manual elimination. Light traps can be used to capture the adults.

982 Coffee Pests and their ManagementCBiological Control

Biological insecticides such as Bacillus thuringiensis Berliner should be used, particularly at the begin-ning of infestations, when the larvae are small.

Chemical Control

Insecticides can be incorporated into the soil, before or after sowing, for cutworm control. Granular products are used in a preventive manner. The use of poisoned baits during the night and dry weather is also recommended.

Brown Coffee Borer, Xylosandrus morigerus (Blandford) (Coleoptera: Curculionidae: Scolytinae)

Distribution

This pest comes from the Oriental region, having its distribution center in the Indomalayan area. It was detected in the western hemisphere in 1958–1959, and it is now found from Veracruz, Mexico to Brazil.


Various tree species can be attacked by X. morigerus (e.g., avocado, cacao, cedar, coffee). This insect dis-plays a strong preference for attacking robusta cof-fee, C. canephora. Some reports indicate that it may also infest C. arabica; however, this has not been confirmed in Mexico. The attacked coffee plant branches and young stems typically display a few or many holes of about 1.0 mm diameter. Blackening of the tissues may be seen around the perforations. A longitudinal cut of an affected branch reveals a gallery in which the whitish lar-vae can be observed, along with reddish brown adults. The attacked young branches and stems dry up distally and then die. Apparently, the

mortality of the branches and stems is caused by microorganisms that invade the plant tissues through the feeding sites formed by the brown coffee borer. Ants, termites or mites can be found in the abandoned galleries. Often the ants cause the death of branches or stems when enlarging the abandoned galleries of X. morigerus to construct their own nests. If death of branches or stems does not occur, the yield is reduced as a result of dam-age to the flowering and development of the fruit. The symptoms can be observed more frequently on weak coffee plants, but attacks may also be seen on the young stems of pruned plantations. This pest is particularly important in Ecuador. In Mex-ico, X. morigerus is also an important pest in the Soconusco region in Chiapas.

Description

The egg is oval, white and very small. The larva is milky white, with a yellowish head, and lacks legs. The pupa is white initially, turning cream to brown toward maturity. The adult is cylindrical and from 1.40 to 1.90 mm long. It is differentiated from other species of the same genus by the bright brown-reddish color, by the stouter body and because the declivity commencing only on-third of the elytral length from the base, and by the near absence of punctures on the sides of the elytra (variable). Females have well-developed wings and fly, but males are incapable of flight. Females are larger than males.

Biology and Ecology

Mated females take flight during the day, leaving the gallery where they developed in search of branches or stems, which they penetrate to construct the new galleries. The female lays from 20 to 60 eggs in 8–10 days. X. morigerus is an ambrosia beetle. The adults and larvae get more nutrition by feeding on fungi (e.g., Ambrosiaemy-ces zeylanicus Trotter is reported from Ecuador;

983Coffee Pests and their Management CRaffaelea tritirachium Batra from Mexico) than from the coffee plant tissues. These fungi grow inside the gallery, which is inoculated by the found-ing female. The larvae have three instars. The life cycle, from egg to adult, is 20–40 days. A gallery may contain more than 80 individuals in all stages of development. The sex ratio in galleries is female-dominated; various studies have found only one male for each 7, 11 or 20 females. Mating occurs within, or very close to the gallery. Infestation is apparently less evident under drought conditions, because the ambrosia fungi require moisture. Nev-ertheless, reports from Ecuador indicate that the populations are larger during the dry season of the year. X. morigerus is a pest which frequently attacks healthy plants; however, very strong attacks may be observed when the coffee plants have been weak-ened by droughts, malnutrition, nematode attacks and competition with weeds. The attacks may be accompanied by attacks from other Scolytinae.

Natural Enemies

No native parasitoids of this pest have been reported in coffee growing countries in tropical America. However, it should be mentioned that in Indonesia, a Tetrastichus sp. (Eulophidae) has been reported, and also probably a bethylid parasitoid. In Ecuador, ants (Formicidae) have been recorded as predators of the brown coffee borer, including species of Crematogaster, Leptothorax, Pheidole, Pseudomyrmex and Solenopsis. The entomopatho-genic fungus B. bassiana has been reported infecting this insect pest.

Management

Sampling

No sampling methods have been developed in coffee plantations; however, some studies indicate that penetrated branches and stems have an aggre-gated distribution in the field. Traps baited with

ethanol have been used for monitoring flying females in robusta coffee plantations.

Cultural Control

Infested vegetative material, particularly in young or pruned plantations, should be cut and burned periodically. Adequate fertilization should be applied. Shade of coffee should be regulated by pruning. Weeds should be suppressed by shading, mulching, use of ground cover, and by selective weeding by hand.

Biological Control

This approach has not yet been attempted for this species.

Chemical Control

This is recommended when the beetle population has undergone a marked increase and natural and cultural control cannot restrain it. Insecticides are useful only when adults are out of the galleries or are boring on the branches; once they have taken refuge within the galleries, insecticides have little or no effect on X. morigerus.

Stem Borers Plagiohammus spp. (Coleoptera: Cerambycidae)

Distribution

Three species of Plagiohammus have been reported attacking the stem of coffee plants in Mexico and Central America. P. maculosus (Bates) has the wider geographic distribution (Costa Rica, El Salvador, Guatemala, Honduras, Mexico), while P. mexicanus Breuning and P. spinipennis (Thomson) have been recorded attacking coffee only in Mexican plantations.

984 Coffee Pests and their ManagementCDamage and Economic Importance

A pile of white-yellowish sawdust or powder present at the base of coffee plants, at the soil level, in a good indication of infestation by Plagiohammus. Infested plants may have a withered, yellow-like and decay-ing appearance. Careful observation at the stem base may help identify the hole or holes (ca. 5.0 mm in diameter), where the sawdust originates. A longitu-dinal cut of the stem and root may uncover a large, white or creamy-colored larva with long gallery containing powder; the gallery begins at the stem and may go as low as the tip of the central tap root. These borers are one of the most destructive coffee plant pests in certain areas of tropical America. The damage is caused by the larva when it bores into the stem and the root. The borer attack delays the plant growth and it may cause death directly by damaging its root, or indirectly, by facilitating stem breakage following wind action or other factors.

Description

The egg is unknown. The larva is creamy-white, with the thorax wider than the abdomen, and legless. Its head is light brown with strong and visible mandibles extended forward. A well-developed larva is about 4.5 cm long. The pupa is brown and similar in size to the adult. The adult has an elongated body, cylindri-cal, from 2.0 to 3.5 cm long by 0.8 cm wide. The body is light brown with two white lines on the prothorax and with irregular white spots on the elytra. The antennae are longer than the body (4.0 cm).

Biology and Ecology

Not much is known about the bionomics of Plagio-hammus spp. Adult females lay eggs on the bark of coffee plant stems, at a height below 30.0 cm. Upon eclosion, the larva penetrates the stem and bores longitudinally all the way to the root, while it feeds, grows and develops. The larvae may be found in the stem, from the base to a height of one meter. When

ready to pupate, the larva moves close to the excre-tory opening, which has been made close to the ground, and it isolates itself within the stem in a chamber surrounded by sawdust. The larval period lasts from 2 to 3 years. Adults are more visible at the beginning of the rainy season (April through June), the period when egg laying occurs. The abundance of these cerambycids is higher in high-altitude cof-fee plantations (>1,000 m) and in places with long summers or with lack of rain. Abandoned coffee plantations are more severely attacked.

Natural Enemies

There is no information on the natural enemies of the Plagiohammus spp.

Management

Sampling

Coffee plants having sawdust as the base of the trunk should be searched for. If damage is recent, the sawdust is white or pale yellow.

Cultural Control

Infested stems should be removed. Adequate fertilization should be applied. Weeds should be managed by shading, mulching, ground cover, and mechanical removal.

Biological Control

This has not been attempted yet.

Chemical Control

In places where the pest appears yearly, a preven-tive insecticide application with a brush or a

985Coffee Pests and their Management Cmanual pump is recommended, treating from the stem base up to 60.0 cm high. Application may be repeated once or twice every 20 days. In order to kill the larva within the stem, a cotton ball soaked in an insecticide can be inserted through the respiration and excretion opening made by the larva, or insecticide solution can be injected into the opening with a syringe. When treating in this manner, the orifice is enlarged, the product is applied and the orifice is sealed with mud, clay or any other material that solidifies. This step, though effective, can be expensive due to the labor it may require.

White Grubs (Coleoptera: Scarabaeidae)

Distribution

Phyllophaga is a well-represented genus of white grubs in coffee plantations in tropical America (Table 17). In El Salvador, P. latipes (Bates), P. men-etriesi (Blanch) and P. obsoleta (Blanch) are found, whereas in Costa Rica P. sanjosecola Saylor and P. vicina (Moser) are reported. Other white grubs recorded in coffee are Anomala sp. (El Salvador) and Dyscinetus picipes Burmeister (Cuba).


White grubs attack the coffee plant root. The damage is caused by larvae that live in the soil and feed on the root system of the plant. In the seedbed and plant nursery, the plants wither and die rapidly; in the coffee plantation, irregular areas on one or several coffee plants, usually young, may be observed, which show symptoms of yellowishness, limited growth, scarce fruits and mummified fruits. When the affected plants are taken out of the soil, lesions, very few small roots and partial or total bark peeling on the main and secondary roots are observed. In some coffee growing areas, these pests can be economically

important, because they may cause death of the plants. The attacks are more severe in plant nurseries, on recently transplanted coffee bushes and on 1 year-old plants, although mature plantations may also suffer the attacks of these pests. In some plantations it is esti-mated that 2 or 3% of the transplanted coffee plants may be lost to white grub attack. Coffee plantations located in the vicinity of pastures are most affected.

Pest Description

The egg is white; when recently laid, they are elon-gated, and later on they adopt a round shape. The larva has a milky-white colored body with a “C” shape, with long thoracic legs covered with hair. The head is dark or light, with strong mandibles. There are three larval stages; the last stage grows up to 3.5–4.0 cm long. The pupa is brown-golden in color, with a size that varies between 1.8 and 2.0 cm. The adult is a strong, heavy bodied scarab. Depending on the species, they may be light or dark brown or reddish-brown in color, measuring from 0.5 to 2.5 cm in length; the antennae are enlarged distally, with the apical expansion consisting of several laminated segments. They are able to fly.

Biology and Ecology

Adult females, which have twilight habits, come out at the beginning of the rainy season and they lay their eggs within the first 10.0 cm of depth in the soil, close to pastures or fodders. The eggs are laid one by one or forming small groups. A female may lay up to 200 eggs. Small larvae feed them-selves with organic matter and small roots, and when they reach the last development stage, they are voracious root eaters. They are found at dif-ferent depths, according to the soil temperature and humidity. They are common in areas that have been gramineous pastures. The larval stage lasts about 6 months. Pupation takes place in a chamber or cell located in the soil at a depth between 10.0 and 20.0 cm. The duration of the life cycle, from egg to adult, varies from 9 to 10

986 Coffee Pests and their ManagementCmonths. Adults are strongly attracted by artificial light and they feed from the leaves of some plants, such as cassava, African oil palm and Erythrina trees (Fabaceae).

Natural Enemies

The larval parasitoids Campsomeris, Elis and Tiphia (Hymenoptera: Scoliidae) have been reported in coffee plantations. Parasitism of bac-teria Micrococus sp. on larvae and parasitism of fungi Spicaria sp. and Metarhizium sp. on pupae has been observed. Nematodes as parasites of lar-vae have been observed as well. A robber fly Diog-mites species (Diptera: Asilidae) has been recorded predating larvae in the soil. Several mammal, reptile and bird species predate on the adults.

Management

Sampling

Root and soil samples at a depth of up to 20.0 cm should be taken, in order to determine the infes-tation sources. The samples are taken from three coffee plants, at 30.0 m intervals. On areas <7 ha, sampling should be taken diagonally and for larger areas sampling should be taken in parallel.

Cultural Control

Weeds should be suppressed principally by shading, by mulching, by ground cover vegeta-tion, by slashing back and by selective weeding by hand. Shade trees should be pruned.

Physical-Mechanical Control

During preparation of the seedbed or plant nursery, the soil to be used for bag filling should be sifted, and the larvae found therein killed

manually. Light traps, preferably 40 watt black-light traps, should be used to capture and eliminate adults. The use of a trap for every 10–15 ha is rec-ommended, which should be turned on from 18:00 to 21:00 o’clock. This procedure has the disadvan-tage of attracting a number of other night habit insect species, which should not be eliminated.

Biological Control

Biological control has not been attempted in cof-fee plantations.

Chemical Control

In the case of plant nurseries and recently trans-planted coffee plants (<1 year old), one larva per plant justifies the use of granular insecticides. The application can also be made at sowing time. With three large larvae or seven small larvae per square meter, insecticides are recommended for young plants. Three year old plants withstand up to eight larvae; for 4 year-old plants, 12–15 larvae; well-attended mature plantations with-stand up to 20 larvae per coffee plant.

Black Citrus Aphid, Toxoptera aurantii (Boyer De Fonscolombe) (Hemiptera: Aphididae)

Distribution

This aphid comes from the tropical and sub-tropi-cal areas of the Old World. It is widely distributed in coffee plantations in tropical America.


T. aurantii attacks leaves, buds and other tender parts of the coffee plant. Coiled, deformed and curled leaves and tender buds are signs of infestation;

987Coffee Pests and their Management Calso, reduced growth, and leaf and flower drop occur. Damage may occur in seedbeds, plant nurs-eries, and on adult coffee plants. Yellow, green or black insect colonies, more or less round shaped, can be found on the lower surface of foliage. They are easily excited, producing a characteristic noise which may be audible if the colonies are very large. The infestation may be accompanied by a fungus, called sooty mold, on the foliage, and also by the presence of ants. In general, this aphid is not very important as a pest; however, a considerable yield reduction may appear when severe and prolonged attacks occur, particularly if the infestation appears during the flowering and fruiting season. The damage is often more severe in the plant nursery, on growing plants. T. aurantii is reported to be responsible for the transmission of pathogens to coffee plants in Costa Rica and Guadeloupe.

Description

The nymphs are similar to adults, but smaller and dark-brown in color. The adults have a globoid, dark green or black body, and they may or may not have wings; apterous females are larger (2.0–2.1 mm) than winged ones (1.7–1.8 mm). They bear a pair of cornicles on the back of the body.

Biology and Ecology

Adult females generally reproduce by parthenogen-esis and are viviparous. Males are winged and rarely seen. An apterous female may produce 50 female nymphs in 7 days. The life cycle, from nymph to adult, is 6 days at 25°C. These aphids excrete honey-dew on which the sooty mold fungus grows. The fungus gives a blackish appearance to the plant. The honeydew is highly appreciated by ants; hence the association of ants with aphids, providing them with protection and transport to other plants. T. aurantii finds conditions more favorable during the dry sea-son. When conditions are adverse, winged females are produced in order to disperse and colonize new plants. Infestations appear in a cyclic manner.

Natural Enemies

More than 70 species of natural enemies have been reported on T. aurantii around the world. In coffee plantations in tropical America, the following have been reported: the braconid parasitoids Diaretus sp. and Lysiphlebus testaceipes (Cresson); the entomopathogenic fungus Acrostalagmus albus Preuss; the coccinellid predators Hippodamia sp. and Cycloneda sp.; the syrphid predators Allograpta sp., Paragus borbonicus Macquart and Baccha clavata Fabricius; and the green lacewing predator Chrysopa sp. (Chrysopidae).

Management

Sampling

Growers are advised to monitor young leaves throughout the dry season for aphids or damage.

Cultural Control

Reinforce shade of coffee plantation during the dry season. Affected plants should not be transplanted.

Biological Control

It is generally acknowledged that natural enemies contribute importantly to prevent T. aurantii from having greater economic impact. Natural enemies should be conserved.

Chemical Control

If chemical control becomes necessary, either insecticidal oil or an insecticide may be used. Chemical control should only be applied at the first signs of damage during periods of young leaves’ growth. Young leaves should be completely moistened after application of chemicals.

988 Coffee Pests and their ManagementCLeaf-Cutting Ants, Atta and Acromyrmex (Hymenoptera: Formicidae)

Distribution

Leaf-cutting ants of the Atta and Acromyrmex genera are found in Neotropical countries where coffee is grown. The principal leaf-cutting ant species affecting coffee plants in tropical America are shown in Table 17.


Leaf-cutting ants attack leaves, tender buds and flowers of the coffee plant. The leaves of attacked coffee plants have semi-circular cuts or these plants are completely defoliated. Leaf fragments dispersed on the ground are seen around the defoliated plants. In recent attacks, the presence of ants carrying leaf and flower pieces may be observed. It is possible to detect earth mounds (nests) nearby or relatively far away.

Situations in which ants are direct plant pests are rare; however, in the tropical and sub-tropical areas of America, ants of the Atta and Acromyrmex genera can constitute important pests of many cul-tivated and wild plants. In tropical America, cutting ants constitute the dominant group of herbivorous animals, because they consume much more vegeta-tion than any other animal group. In the case of coffee, these ants are generally considered of minor importance. Nevertheless, in some areas like the Turrialba region of Costa Rica, A. cephalotes attacks on coffee plants can be severe in monocultures. The damage is caused by the worker caste when they cut the coffee foliage and flowers with their mandibles. In some Atta species, from 5 to 28 colonies/ha have been observed, with the possibility of having one or more millions of workers in each colony. The nests they construct may have dimensions that vary between 30 and 600 m2. From one day to the other, one or more coffee plants may be completely defo-liated by these ants. Coffee plantations near woody or weedy areas are attacked more commonly.

Pest Description

Atta cephalotes (L.) is hereinafter described. Their colonies contain three castes: queens, males and workers. Queens are big (16 mm), with a strong brown-reddish color, and they have wings (although they lose them after the nuptial flight); also, they have a pair of horns on the occipital lobules and another pair on the lower part of the head, close to the mandibles. Males are winged but smaller (13 mm) than the queens, and they do not have the aforementioned horns. Workers are wingless. Sol-dier workers present abundant yellowish hair on the forehead sides, and they are about 13–15 mm long. Forager workers have less hair and they are about 9–10 mm long; fungus-cultivator workers are lighter colored and smaller (from 2 to 4 mm).

Biology and Ecology

Atta and Acromyrmex ants are social insects that use plant leaves to cultivate symbiotic fungus (Leucoagaricus gongylophorus (Möller) Singer; Attamyces spp.), which serves as their foodstuff. They form colonies constituted of three castes: queens, males and workers; the latter are sterile and present acute polymorphism and functions (soldiers, foragers, cultivators). The mating of queens with males takes place outside the nest during the nuptial flight, at the beginning of the first rains. Newly mated females dig their nests in the soil and begin to cultivate the fungi which will serve as their food and to lay their first eggs. The eggs give birth to the larvae and after 40–60 days, the first adult workers emerge. New colonies have a single tower-like mound of small size of <200 cm2 in area, and with a small entrance hole, whereas older colonies are flat-tened, with larger entrance holes and a colony surface area >200 cm2. The growth of the colony is very slow at the beginning, but during the second and third year it accelerates rapidly and then it diminishes as the colony starts production of males and winged queens. Towards the end of the

989Coffee Pests and their Management Cthird year, the population is enormous, and it is possible to observe more than 1,000 entrance/exit holes on the nest. The Acromyrmex nests are simpler than those of Atta. In order to reach the plants which serve as their food, the forager work-ers move from the nest, which is often in non-cultivated fields, through narrow paths which can go more than 100 m in distance. The workers’ activity is more intense during the night.

Natural Enemies

Apparently these ants have few natural enemies. Several predators, such as birds, toads, lizards and anteaters feed on the queens and males during the nuptial flight. In Colombia, other carnivorous ants have been observed to be predators of leaf-cutting ants. The importance of all these natural enemies in regulating leaf-cutting ant populations is unknown.

Management

The optimal time of the year to control leaf-cutting ants has not been determined. However, the nup-tial flight period, a crucial event within the ant life cycle, should be taken into account. Considering the ecological importance of leaf cutting ants as plant population regulators in woody and grazing areas, and taking into account that in certain areas they are eaten by humans, it is recommended that population regulation, not elimination, be the primary goal.

Sampling

No sampling techniques have been developed for leaf-cutting ants in coffee plantations. The nests can be located by following the narrow paths used by the ants. Ant colony density can be estimated by sampling four 125-m2 plots at each edge of a farm (north, west, east and south), and a single 500-m2 area in the center of the farm (a total area of 1,000 m2).

Cultural Control

Queens should be eliminated at the recently formed nests using a grub hoe. Repellent plants (e.g., sor-ghum) should be sown. Because coffee on farms with low vegetational diversity is at greater risk of attack by A. cephalotes, it is recommended that shade trees be planted in order to increase shade levels and therefore to decrease ant colonization. Also, it may be desirable to plant shade trees that are palatable to leaf-cutting ants, but that should be either not commercially valuable (e.g., Erythrina poeppigiana [Walp]. Cook, Cordia alliodora (Ruiz & Pav.) Oken, Swietenia macrophylla King, Cedrela odorata L.), or that are tolerant of ant attack, in order to divert ants from foraging coffee plants.

Biological Control

Some entomopathogenic (e.g., Paecilomyces sp. and M. anisopliae) and antagonist (Trichoderma viride Persoon ex Gray) fungal strains have proved to be successful against leaf-cutting ant colonies in experimental studies. However, the practicality of these fungi has not been assessed in commercial coffee plantations.

Chemical Control

Insecticides are applied directly through some of the entrance/exit holes of the nests, taking the precaution of plugging or closing most of them before. The “ant hill beating” procedure may also be used, which consists of digging in the nest with a shovel in order to uncover the ant brood, and spraying them with insecticide. Also, leaf-cutting ants can be successfully controlled using baits containing insecticides. Treatment results can be improved by basing the amount of insec-ticide applied on an estimate of the colony volume, instead of surface colony area. An experimental study shows that mounds of dump material can be used as a highly effective

990 Coffee Pests and their ManagementCsmall-scale deterrent to protect Hibiscus plants from defoliation by A. cephalotes, but this method has not been tested in coffee.

Long-Horned Grasshoppers or Katydids (Orthoptera: Tettigoniidae)

Distribution

Two Idiarthron species, I. subquadratum Saussure & Pictet and I. atrispinum (Stål), and one unknown Gongrocnemis species have been reported attacking coffee in Mexico and Central America; apparently, I. subquadratum is present in Colombia too. Of these, I. subquadratum is the most important katy-did pest in coffee because very high infestations have been reported in some coffee plantations in El Salvador and Mexico. Most of the information available on katydids comes from this species.


Attacked coffee leaves show irregular holes mar-ginally and centrally; feeding can also be observed on the tender buds, shoots and branch tips. A char-acteristic symptom of katydid damage is the appearance of green and ripe fruits with damaged pulp, so that the coffee beans are exposed. The damage is caused by both the nymphs and adults. In coffee plantations where heavy attacks of I. sub-quadratum occur, complete destruction of leaves, buds and small branches, the fall of tender fruits and the destruction of fruits can be observed. In general, I. subquadratum is not an economically important problem in coffee, although it some-times may create some concern in certain areas of Central America and Mexico. In southeastern Mexico (Siltepec, Chiapas), the most critical attack period is from June through November. Damage is more important in very shaded and abandoned coffee plantations. In addition to direct damage caused by I. subquadratum, plant pathogenic

fungi may be involved in the damage (e.g., Phoma costarricensis Echandi).

Description

The eggs of I. subquadratum are brown in color, elongated, with a hard chorion; they are oviposited in compact clusters. There are six nymphal instars. Newly emerged nymphs are fragile and gray in color. Nymphs resemble adults, but are smaller, lighter colored, and lack wings. Nymphs and adults have strong and large mandibles and the antennae are very thin and longer than the body. Adults have a heavy set, more or less cylindrical body, greenish, brown-gray or light gray in color, with females from 5.0 to 6.0 cm long. Males are smaller. With their thorny, strong and long back legs, they can jump. Their ability to fly is limited and in general their movements are clumsy. Females have an ovi-positor, from 1.0 to 2.3 cm long, at the tip of the abdomen, which looks like a spur or a knife point.

Biology and Ecology

Idiarthron subquadratum is arboreal, polyphagous, and nocturnally active. Both nymphs and adults leave their daytime shelters at night and disperse by jumping between tree and bush canopies. They hide in shady places, such as dead leaves, rotten trunks and weeds; in particular, they take refuge in plants of wind-breaks, izote (Yucca guatemalensis Baker) barriers, banana plants (Musa spp.) and Sanseviera sp. This species feeds on leaves and fruits of several plants, including coffee (Coffea spp.), banana (Musa spp.), orange (Citrus spp.), chayote [Sechium edule (Jacq.) Swartz], and pacaya (Chamaedorea sp.). Mating occurs in plant cano-pies at night or in daytime shelters. Adult females place their eggs in the soil and, in some cases, under the bark. The eggs are placed in a mass (from 5 to 50), and one female may lay several hundred. In Siltepec, Chiapas, Mexico, mating usually occurs in October, and oviposition occurs

991Coffee Pests and their Management Cin November and December. Adults are killed by low temperatures in January and February, and eggs undergo diapause. At the beginning of the rainy season, between May and June, nymphs emerge and start to feed on coffee plants. Genera-tions are overlapping in warmer regions. The life cycle from egg to adult is about 80 days at 28°C. In El Salvador, this pest is especially common in high altitude coffee plantations.

Natural Enemies

Birds, spiders, parasitic nematodes and an unknown tachinid fly species (Diptera: Tachinidae) have been reported in Mexico.

Management

Sampling

“Shelter traps” made with a 10-cm-diameter by 30-cm-long bamboo (Bambusa vulgaris Schrad.) internode closed at one end, can be used for sam-pling I. subquadratum. The bamboo traps are placed on coffee bushes upon the first rainfall events, and during daytime are checked every week for captured insects.

Cultural Control

Weed control should be applied. The shade should be regulated. Trash and rotten trunks in the coffee plantation should be prevented. Dry banana and plantain leaves should be eliminated.

Mechanical Control

Bamboo traps as described earlier for sampling can be used for elimination of I. subquadratum. The traps are placed in dark spots of the plantation and in the vicinity of the plants that are normally used as refuge. The traps are checked weekly and

the insects are killed manually and/or used as food for domestic animals (e.g., chickens and dogs).

Biological Control

Some strains of B. bassiana kill nymphs in the lab-oratory. However, the use of this biocontrol agent has not been attempted in field.

Chemical Control

When infestations are heavy, the application of chemical insecticides at the places of refuge is recom-mended. Toxic baits placed inside the bamboo traps are also recommended. The most convenient period for chemical control is 1 month after the beginning of rainfall and before oviposition takes place. Because high infestations of the pest have been related to low populations of natural enemies, insecticide use should be avoided in order to conserve natural control.

Bush Crickets, Paroecanthus spp. (Orthoptera: Gryllidae)

Distribution

Bush crickets appear sporadically, affecting coffee plants and shade trees in coffee plantations in some areas of Central America and Mexico. The reported species are Paroecanthus guatemalae Saussure (Guatemala, Honduras) and P. niger Saussure (El Salvador, Guatemala). The Paroecanthus species in Mexico remains unknown. Recently, high infes-tations of bush crickets have been reported in Honduras.


Paroecanthus spp. attack lignified stems and branches of coffee bushes and shade trees. The affected plants show small marks or holes, 3.0 mm

992 Coffee Pests and their ManagementCin diameter by 1.0 mm in depth, distributed in line throughout the affected stems and branches. This mark along the stem gives it the appearance of a flute; hence this damage is known as “flute disease.” If the stem or branch bark is lifted right below each hole, an “X” shaped scar on the wood may be observed. The damage is caused when the adult female of the cricket lays its eggs. Heavy attacks of the bush cricket (when there are many holes), may cause physiological disorders in the coffee plant, which affects its development. The cricket can be a pathogen vector, or perhaps the lesions may favor the penetration of diseases. A severe infestation can kill the coffee plant. In Honduras, where high infes-tations have been reported, the affected plants develop a yellowish color and they lose leaves and fruits.

Description

The egg is white with elongated shape (1.0 by 5.0 mm). Nymphs are similar to adults, but their wings are not well developed and they are smaller than adults. The adult has a cylindrically shaped body and is 2.0–2.5 cm long. The legs are yellowish in color and the abdomen is dark brown. The antennae are filiform and their length is almost twice the size of the body. In the female, the wings do not cover all of the abdomen, which at its tip shows the cerci and a long pin-shaped ovipositor.

Biology and Ecology

The bush cricket is active at night, while during daytime it takes refuge in dark places in the weeds, dead leaves and some plants such as bananas (Musa spp.) and izotes (Y. guatemalensis). Only on cloudy days and when it is very abundant can it be seen during the day. The female lays about eight eggs in each oviposition hole, distributing two on each end of the scar it makes on the wood, in an “X” shape. The nymphs emerge in about 3 weeks, and they go through several molts for 3 months before becom-ing adults. Nymphs and adults can feed from the

coffee plant. Three or four generations appear per year. The attacks are more severe in unshaded coffee plantations. In Honduras, acute infestations have been reported in the dry season in plantations located between 900 and 1,250 m above sea level.

Natural Enemies

An egg parasitoid wasp, Acmopolynema sp. (Hymenoptera: Mymaridae), has been reported in Honduras and Mexico.

Management

Sampling

Scouting should be conducted to determine the limits of the infestation during the dry season. Upon detection of damage, the trunk bark should be scratched in search of the insect’s eggs. If the damage is recent, the perforations are white and unhatched eggs shall be observed; if the damage is old, the perforations are dark and the eggs have hatched.

Cultural Control

Weeds should be controlled within and on the edges of the plantation. Severely damaged plants should be re-planted, or pruned of the affected stems, and burned thereafter to eliminate the eggs.

Biological Control

This has not been attempted.

Chemical Control

In plantations that are close to the affected planta-tions, a preventive insecticide application with a brush or a manual pump is recommended, treating from the stem base up to 60.0 cm high. Application may be

993Coffee Pests and their Management Crepeated once or twice every 20 days. Also, an insecti-cidal dust can be directed to the main stem, to the soil, and to the plantation edges during the dry season.

Leaf-Eating Caterpillars (Lepidoptera)

Distribution

There is a large and diverse group of leaf-eating caterpillar species in tropical American countries affecting coffee. The principal leaf-eating caterpil-lars are shown in Table 17.


Coffee bushes affected by leaf-eating caterpillars show totally or partially consumed leaves. Some-times the fruits are also affected. Eventually, voracious worms or caterpillar larvae, as well as, their feces, can be observed. Some of these are urticating caterpillars. These insects are frequently mentioned in the coffee pest manuals of South American countries, such as Brazil and Colombia. Some species even defoliate entire sections of the coffee plantation.

Description

As example of leaf-eating caterpillars, Oxidia sp. (Geometridae), is described. When small, they are black, and when large, they are light gray. These caterpillars attain a length of 5.0–6.0 cm. The lar-vae are called inchworms or measuringworms.

Biology and Ecology

Adults lay their eggs individually or in groups on the foliage of various plants. The larvae or worm feeds on the foliage. The caterpillar goes through several molts, and as it grows, feeds itself voraciously. Some

species, such as Phobetron hipparchia (Cramer), Sib-ine spp., Olceclostera moresca (Schaus), Megalopyge lanata (Stoll & Cramer) and Automeris sp., among others, have urticating hairs which cause painful lesions to anyone touching them. Measuringworms, which are active nocturnally, possess camouflage which allows them to go unnoticed during the day. In general, the pupation takes place in the soil. In Ecuador, Automeris sp. and Eacles masoni Schaus appear cyclically during the rainy season. The adults or moths have nocturnal habits. Insecticide abuse and climatological changes can affect the natural enemies of leaf-eating caterpillars, so their popula-tions may increase and become damaging.

Natural Enemies

There are many natural enemies of leaf-eating cat-erpillars. Among them, birds, parasitic Hymenoptera and Diptera, and fungal, bacterial and viral dis-eases are notable.

Management

Sampling

Regular inspection of the coffee plantation should be made to detect initial infestation sources.

Mechanical Control

The larvae of urticating worms should be elimi-nated manually using gloves. In the case of mea-suringworms, the same can be done, but at night. Adults should be eliminated with light traps.

Biological Control

Bacillus thuringiensis Berliner can be used, partic-ularly at the beginning of infestations when the caterpillars are small.

994 Coffee Pests and their ManagementCChemical Control

Some organophosphates and pyrethroids are recommended. In general, the use of chemical insecticides is not necessary, because the natural enemies provide regulation of the populations of these leaf-eating caterpillars. Thus, it is important to preserve the natural enemies, and use insecticides only in extreme cases.

Leaf Weevils (Coleoptera: Curculionidae)

Distribution

Various leaf weevils are present in coffee planta-tions in tropical America (Table 17).


Leaf weevils attack the coffee bush leaves. The leaves show irregular holes, tearing and notches on their edges, often beginning at the tip and from the edge towards the vein. The most affected parts are new leaves and shoots. The damage is caused by the adults, which feed on the coffee foliage. The attack of these weevils can become important when they affect the buds of recently pruned plants and of trees <1 year old. The lesions caused by this pest on the leaves may favor the infection of P. costarricensis.

Description

Larvae are whitish and legless. The color of adults varies according to the species, being off-white (Compsus sp.), light brown with yellow spots (Macrostylus sp.), grayish, light brown or black (Epicaerus capetilensis Sharp.) or green. Their size varies from 9.0 to 13.0 mm. The snout is fairly well developed in these insects.

Biology and Ecology

Adults feed from the foliage of coffee and other plants. A distinctive characteristic of these weevils is that when they feel threatened they contract their legs and snout and let themselves fall to the ground where they seemingly disappear. Their eggs are laid in the soil and the larvae lead a sub-terranean life (between 10.0 and 20.0 cm deep), feeding from weed roots, including the coffee plant root. The weevil populations are higher from June through August in Honduras. In Brazil, Pantomo-rus leucoloma (Boheman) is more frequent in the summer and it attacks both C. arabica and C. canephora. In Honduras, the most frequent attacks appear in the highest altitude areas. Very weedy areas favor infestation.

Natural Enemies

Predation by assassin bugs (Hemiptera: Reduvii-dae) is reported in Costa Rica.

Management

Sampling

Tender buds and new leaves of the coffee plants should be checked. When the damage only appears on old leaves and not new ones, no control mea-sure should be initiated.

Cultural Control

Weeding should not be complete, so that adult and larvae weevils have a feeding source and abstain from attacking the coffee plants.

Biological Control

It has not been attempted.

995Coffee Pests and their Management CChemical Control

When the populations are large, applications of insecticides to the foliage and then to the soil are recommended.

Coffee Bean Weevil, Araecerus fasciculatus (De Geer) (Coleoptera: Anthribidae)

Distribution

Present in all coffee growing countries in America.


Araecerus fasciculatus attacks stored coffee beans. Coffee beans stored in warehouses, coffee mills and other places used to gather the harvest will show per-forations and irregular and relatively large galleries caused by this weevil. Accumulation of a fine yellowish powder is also observed. Highly infested warehouses will have a large number of little beetles, +the walls, roofs and windows. This weevil, which attacks a wide variety of grain in storage, is considered as one of the few economically important pests of stored coffee in the American countries, particularly in South America. It creates problems in warehouses that store poorly processed coffee containing more than 12% humidity. The damage is caused by the weevil larvae, which live in and feed on the grains. The attack is also favored when the warehouse tem-perature is higher than 27°C and relative humidity is above 60%. In 6 months of infestation, losses of 30% have been estimated. C. arabica apparently is more susceptible than C. canephora. The fruits that remain on the plant after harvest may also be attacked.

Description

The larva is without legs, white, with a “C” shaped body and a relatively wide thorax. The head is small, light brown in color. They measure from

5.0 to 7.0 mm. They have about five molts. Pupal size varies from 3.0 to 4.0 mm. The adult is oval, with an arched body, covered by hairs and with a length of 2.5–4.5 mm. The head has round promi-nent eyes, with a short, wide, curved-downwards “snout” and the mouthparts distally.

Biology and Ecology

Adult females lay eggs on the parchment coffee grooves, placing one per grain and approximately three per day. The average number of eggs laid is 52. Larvae create galleries in the seed, and they pupate there also. The life cycle, from egg to adult, is 35–40 days. Between 55 and 74% of the descen-dants are composed of females. Infestation is more acute on softened coffee beans. Up to ten genera-tions are reported per year.

Natural enemies

In Colombia, the following natural enemies of A. fasciculatus have been reported: Anisep-toromalus calanadrae (Howard) (Hymenoptera: Pteromalidae), Cephalonomia gallicola (Ash-mead) (Hymenoptera: Bethylidae), Cheyletus sp. (Acari: Cheyletidae) and Monieziella sp. (Acari: Tyroglyphidae).

Management

Sampling

Fortnight visits should be made to the storehouses to check the presence of weevils, particularly in the wet season and in places with very humid weather.

Cultural Control

Adequate fertilizing, harvesting and pulp extrac-tion should be conducted. Coffee should be stored

996 Coffee Pests and their ManagementCwith adequate humidity. Warehouses and storage places should be kept clean. Infested lots should be set aside and placed in the sunlight.

Bilogical Control

It is not conducted.

Chemical Control

In the case of preventive treatments and the treat-ment of infested lots, fumigation is recommended. After fumigation, spraying of a 3-month residual effect pyrethroid with motorized equipment is recommended. The preventive treatment should be conducted when there are 1–2 weevils/m2 of sacks. Treatment of the walls, floor and roof of the warehouse where the coffee is going to be stored is also recommended.

Spider Mites (Acari)

Distribution

At least, six spider mite species have been recorded in coffee in tropical America (Table 17). Olygonychus (Acari: Tetranychidae) is the most representative genus.


Spider mites attack coffee foliage in all their stages of development. Attacked plants present yellowish, brown or copper colored leaves, with more undulated edges. Sometimes the attacked leaves may dry up and fall. Also, the leaves lose their shine and present a dirty appearance. The symptoms take place in large patches in the coffee plantation, and more frequently in old, poorly attended coffee plantations, and near the roads. These symptoms are easily recognized at a distance. Upon examination of the upper face of the leave with

a magnifying glass, little animals moving on the leave can be observed, and in general, silky threads which retain dust and other residues. The damage, which consists of the destruction of superficial cells of the leaf, is caused by immature and adult mites when they feed. Spider mites may be especially important in some areas of tropical American countries during abnormally dry weather. In severe attacks the leaf functions are interrupted and they may drop. Leaf defoliation and yield decreases may occur when more than 30 mites per leaf are present, particularly under dry weather conditions. The economic importance of some species of mites on coffee, for example, Polyphag-otarsonemus latus (Banks) (Acari: Tarsonemidae) in Brazil, is unknown.

Description

The egg is elliptic or spherical, bright orange, red-dish or red in color, depending on the species. Its length varies from 0.100 to 0.127 mm. The larva has three pairs of legs, an almost circular body, and according to the species, orange or yellow col-ored when hatching, turning green-yellowish as they feed. They are from 0.15 to 0.16 mm long. Nymphs (protonymph and deutonymph) have four pairs of legs, and they are ovoid and about 0.20 mm long. In the deutonymph, which is larger, females (0.20–0.26 mm) can be differentiated from males (0.18–0.23 mm). Adult females are larger (0.28–0.50 mm) and more oval than the males (0.25–0.35 mm). Color varies according to the species and the sex; however, colors such as red and orange are blended, and in some cases the mites have spots. The broad mite, P. latus, has a white-milky color and it is smaller than the other species (0.15–0.20 mm).

Biology and Ecology

Adult females reproduce sexually and parthenoge-netically. The eggs are laid one by one, preferentially on the upper face of leaves, close to the veins,

997Coffee Pests and their Management Calthough P. latus, unlike the others, prefers the lower side of the leaves. The eggs may be fixed to the leaf with the silk threads (cobweb) produced by the mites and which serves for protection and for moving from one leaf to another. Unlike the Tet-ranychidae, Tenuipalpidae (Brivipalpus sp.) do not produce silky threads. Egg laying, in the case of Olygonychus coffeae (Nietner), occurs at a rate of 4–6 eggs/day/female for 2 or 3 weeks. Upon eclo-sion, the larvae feed from cells that they puncture with their chelicerae, and in time they become prot-onymphs and the latter become deutonymphs. At the end of their development, both protonymphs and deutonymphs go through an inactive stage called “quiescence.” An accumulation of various residual materials such as dust and the old exuviae of spider mites can be observed in the cobweb pro-ducing species. The egg to adult life cycle varies from 8 to 28 days, according to the temperature. Females mate with one or more males, and a male may fertilize several females. Females, which are more abundant than males, disperse from one leaf to another and from one coffee plant to another, by the use of silk threads. However, the factors that contribute the most to dispersion are the wind, humans and other animals. Spider mites prefer to colonize the sunlit coffee plants and the older leaves, although in severe infestations they also attack the young leaves.

Natural Enemies

Predators such as ladybirds (Coleoptera: Coccinel-lidae) and rove beetles (Coleoptera: Staphylinidae) are reported. However, the literature on coffee pests is not clear about the predator species present.

Management

Sampling

The plantation should be checked during the summer or dry periods, preferably on roadsides. The infestation of a coffee plantation plot is

determined by making parallel inspection routes 25 m apart from each other, and examining 24 leaves at random from four coffee plants every 25 m.

Cultural Control

Shade trees should be planted in very sunlit areas. Weed control should be conducted. Adequate fer-tilizing should be applied.

Biological Control

Not applied.

Chemical Control

Some pesticides have a selective action, affect-ing only mites, and others (non-selective) kill mites and insects. In case of a simultaneous attack by mites and leaf miners, non-selective products are recommended. However, the over-use of this practice can negatively affect the beneficial parasitoids and predators. Applica-tions should be made only to infested areas. Various pesticides are recommended, making one application and sometimes a second one. A population of 30–40 spider mites per leaf in the dry season cause defoliation, so this density must be avoided.

References

Barrera JF (ed) (2002) Tres plagas del café en Chiapas. El Colegio de la Frontera Sur. México, 198 pp

Cárdenas-M R, Posada-F FJ (2001) Los insectos y otros habi-tantes de cafetales y platanales. Comité Departamental de Cafeteros del Quindío. Armenia, Colombia, 250 pp

Castillo-Ponce G, Contreras-J A, Zamarripa-C A, Méndez-L I, Vázquez-M M, HolguínM F, Fernández-R A (1996) Tec-nología para la producción de café en México. Instituto Nacional de Investigaciones Forestales y Agropecuarias. México. 88 pp. Primera reimpresión. Folleto Técnico Núm 8

Coffee Industry Development Company Ltd (1986) Growing coffee in Jamaica. Jamaica, 103 pp

998 Cold Tolerance in InsectsCGarcía-G A, Campos-A O, Barrera-S CA, Meoño-R JE (1998)

Manual de caficultura. Tercera edición. Asociación Nacional del Café, Guatemala, 218 pp

Le Pelley RH (1973) Las plagas del café. Editorial Labor, SA, Barcelona, 693 pp

Matiello JB (1991) O café. Do cultivo ao consumo. Publica-ções Globo Rural. Coleção do Agricultor. Grãos. Editora Globo, SA, Brasil, 320 pp

Muñoz-H R (2001) Plagas insectiles del cafeto. In: Manual de caficultura. Instituto Hondureño del Café, Honduras, pp 115–142

Páliz-S V, Mendoza-M J (1993) Plagas del cafeto. In: Manual de caficultura. Estación Experimental Pichilingue. GTZ, FUNDAGRO, Quevedo, Ecuador, pp 144–166

Cold Tolerance in Insects

david riversLoyola College in Maryland, Baltimore, MD, USA

Exposure to low temperatures is among the most important abiotic factors limiting the range of insects in temperate climates. The relationship between insects and cold is dynamic, particularly when considering the actual temperature at the surface of the integument versus internal and/or ambient conditions, the length of exposure to low temperature, and the degree of temperature fluc-tuation over a defined period of time (e.g., day, week or winter season). These issues make it chal-lenging to categorize insect tolerance to a specific set of temperatures, particularly in terms of sur-vival. As poikilotherms, although some are hetero-thermic under specific conditions, insects have adapted to cold environments resulting in exten-sion of locomotor and/or reproductive activity during low temperature exposure, enhancement of metabolic rate, and maintenance of a positive energy balance. The implications to many of these insects are a lengthening of the life cycle and a requirement for individuals to overwinter one or more times. The actual mechanisms associated with these adaptations have received extensive study in recent years, including attempts to deci-pher the underlying genetic basis of individual and population responses to low temperatures and seasonal change.

Classification of Cold Tolerance

Insect cold tolerance classifications have tradition-ally been divided into freezing tolerance and freeze intolerant strategies. This division has been criti-cized in recent years by a number of investigators. The arguments for the classification scheme have depended on the definitions applied to the two terms, and it is how freezing tolerant and freeze intolerant species have been defined that evokes the controversy. For example, in freeze tolerance, these insects are said to be capable of withstanding ice formation in some or nearly all parts of the body and associated fluids. Most insects in this grouping usually freeze at temperatures between −5 and −10°C, though others require lower temperatures. Once frozen, these species can tolerate cooling to much lower temperatures, and upon thawing, the insects recover and apparently resume normal development and behaviors. Some experts, how-ever, have contended that this example of freeze tol-erance is at the extreme end of cold tolerance and only represents insects which are most suited to survive low temperatures. An examination of some 60–70 species of insects classified as freezing toler-ant has led to the suggestion that there are distinct freeze tolerance strategies that allow insects to be grouped based on supercooling points (SCPs) and lower lethal temperature (LLT): (i) partially freeze tolerant species that survive a small portion of their body water converted to ice; (ii) moderately freeze tolerant species, if the exposure is sufficiently long, die at temperatures <10° below their SCP; (iii) strongly freezing tolerant insect species display LLT twenty degrees or more below their SCP; and (iv) freezing tolerant species possess very low SCPs and freeze at extremely low temperatures. Insects in this latter group are capable of surviving at tempera-tures a few degrees below their SCP.

Insects that are not tolerant of any ice forma-tion in their bodies are generally termed freeze intolerant species. The natural tendency has been to assume that these insects will die if tissues or body fluids freeze, and presumably if they avoid the frozen state, these insects will survive. Such

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