mq 3 - the super mealybug

MQ · 3

MONDOCACTUS

QUADERNI

The Super MealybugObservations on a recently introduced mealy bug species: Hypogeococcus festerianus(Lyzer & Trellers)by Andrea Cattabriga

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Titolo

2

MONDOCACTUS QUADERNI n. 3

The Super Mealybug.Observations on a recently introduced mealy bug species: Hypogeococcus festerianus(Lyzer & Trellers)

by Andrea Cattabriga.Text, drawings and pictures by the author.

Originally published onPiante Grasse,Vol XII, n° 4, Oct-Dec 1992 pp. 108-122.

Digital repring November 2014.

[email protected]

This work is distributed under Creative Commons License Attribution-NonCommercial-NoDerivatives 4.0 International.

Editorial

Dear reader,

the series “Mondocactus notebooks” collects a re-newed edition of the articles devoted to the succu-lent plants that I produced from 1983 until today.

The text of the articles was deliberately preserved in its original form, so any errors in grammar and concept have not been corrected. For this occasion was also produced this version of the English text, accessible by pressing the [EN] at the bottom right of each page. I apologize for the low quality of the translation, accomplished with the tools available on the internet, but its only purpose is to make the least understandable text to an international audience.

Reading the various items you can appreciate signi-ficant variations of the style adopted from time to time, due to both a gradual maturity of expression, and the need to adapt the article to the kind of pu-blication in which it was intended, it was a maga-zine of an association of amateurs, or a commercial journal.

The purpose of this project is to integrate the gene-ral information available on the mondocactus web-site pages with free downloadable documents on specific topics.

good readingAndrea Cattabriga

http://www.mondocactus.com

mailto:info%40mondocactus.com?subject=Richiesta%20di%20informazioni%20da%20Mondocactus%20Quaderni%3A%20

3 – La supercocciniglia

The Super Mealybug.Observations on a recently introduced mealy bug species: Hypogeococcus festerianus(Lyzer & Trellers)

IntroductionIn any ecosystem there are more or less simple re-lationships between all organisms that belong to it. Some of these reports are favorable, as is the case of the symbiosis between fungi and algae in the formation of lichens (in this case, in fact, the two organisms will benefit each other), others are indifferent because nobody gets a real benefit while others are unfavorable for at least one of the parts involved and the latter is the case of parasitism. When parasitism develops in a natural contest exist opposing forces that tend to limit it (such as the existence of other predators, which in turn feed on the parasites); but when the parasites migrate or are made to migrate to new environments in their favor or in the absence of their natural predators their development is no longer limited and may spread to become difficult to control.

The trade of the plants has been and is still one of the main vehicles of spreading plant diseases. Just think of the Colorado potato beetle (Leptino-tarsa decemlineata) or vine phylloxera (Phylloxe-ra vastatrix), insects imported from the Americas, which caused huge disasters in the cultivation of these plants in Europe.

The import of exotic pests through succulents trade in particular is much more intense than you might suppose, and this comes from the fact that currently the plants in question come from many different countries.

This report aims to be a substantial contribution to limit the spread of a peculiar pest that only in

recent years has been in Europe and that, precisely because of its peculiarities, may apply to become one of the most important pests for these types of plants.

Generalities about the most common succulents’ parasitesAnyone who has a little experience with the cul-tivation of succulents knows the susceptibility of these plants against various parasites. Given the high water content, these plants are often attacked by predators thanks to special structures attached to the mouth and part of the buccal apparatus it-self (biting and sucking mouthparts) can penetrate the epidermis of the plant to get to suck the sap from the underlying tissues. Among these bodies more insidious is worth mentioning the red spider mite (often the species Tetranychus urticae) which is a Arachnid order of Acari and far more dangerous Nematodes (Heterodora spp., Globodera spp.) that infest the roots producing small galls and can only be destroyed by heat.

Instead, the most common parasites and that can be controlled more easily are the various species of mealy bugs.

Succulent plants are attacked by these insects both at the level of the aerial part and the roots which evidence is their production of a thick waxy fluff that makes them waterproof. Some species produce a protective scale, which is also made up of wax.

Scale insects have always known in Europe. All


plant collectors have incurred battles, if not real wars, against such pests. To greatly limit the de-velopment of infestations may be sufficient an ac-curate treatment at the beginning and end of the growing season to be performed on all plants in the collection by distribution of specific chemical pre-parations. The occasional and localized treatments, i.e. carried out on individual plants that appear already infested creates a endemic condition, that is a constant presence of insects in various stages of development, which can become epidemic when conditions reach the optimum.

To date in Italy were reported as many as 16 spe-cies of exotic mealybug (Marotta, Garonne, 1991) related to succulents and probably introduced by the trade of the same (we attach the listing of these species separately).

Scale insects, however, are also represented by other species, some of which attack citrus fruits, grapes and other fruit; a species also has been the subject of farming in the past because of its drying was extracted a natural dye of considerable value, the red cochineal, used to dye clothing or colour for miniaturists. The species is native to the Americas (Mexico, Peru), but following his discovery the in-sect was imported by the Spaniards along with the plant, an opuntia, that hosts it in nature and brou-ght up in the Canary Islands in secret. The name of this species is Dactylopius cacti (= Coccus cacti), but the market interest in this insect decreased when synthetic dyes were invented. Lately this natural pigment is returning to be interesting for the market and the breeding of cochineal is also being deve-loped in South Africa. Today, in the Canary Islands Dactylopius cacti spread everywhere and live undi-sturbed on the opuntias that infest the uncultivated places.

Spread of H. festerianus in Italy and EuropeThe warm climate of the Canary Islands has encou-raged various European companies to produce exo-tic fruits (banana, mango, papaya, avocado, etc.) while in the horticultural industry only the cultiva-tion of succulents has developed extensively. This resulted in a steady flow of imports of exotic plants from all tropical areas of the world and especially the arid areas. This has been helped even the use of the islands as a station of acclimatization of plants imported into Europe as early as’ 700 and the set-tlement of important collections of plants collected in habitats such as the great scholar of Cactaceae of South America, Ritter.

You can not know how the homoptera coccoidea pseudococcid Hypogeococcus festerianus arrived in the Canaries, but for sure you know that currently is widespread and that causes the most damage to crops of cacti in most nurseries.

The entrance of the insect in Italy however are easy to rebuild and must bind to the fact that in the last fifteen years has had a tremendous deve-lopment of the collectors of succulents. This resul-ted in a strong demand for plants of a certain size that was answered with the import of specimens from the same Canary Islands. Among the many seedlings purchased there were probably several bearing Hypogeococcus festerianus, which has the effect of causing the plant attacked the deforma-tion of the stems and the proliferation of shoots in an uncontrolled manner.

Following the introduction of H. festerianus in Italy (probably since the early ‘80s) the insect took office in some nurseries specialize in succulent, where it is checked by the use of pesticides but where is always still present with endemic infesta-tions.

The spread is the beginning is nowadays is fa-vored by the fact that the plants in the first stage of infestation maintain an active vegetation and appear very healthy, especially if imporate directly from the Canaries. The deformations are considered so natural and the plants are traded as special clum-ping varieties (especially plants that are normally solitary, as Astrophytum).

Reports on the presence of this insect will have to nurseries in Liguria, Campania, Sicily, Tuscany, Emilia, Lazio and Lombardy. recently has also been reported in the open country, the heliport of Naples (Marotta, pers. comm.) and in Sicily, in a highly

Nursery in the Canaries, with specimens of Espostoa parasitized by H. festerianus


weed, on the aboveground and belowground Cereus spp. reared outdoor or in a cold greenhouse (LONGO MAROTTA Russo Tranfaglia, 1989).

Outside the presence of the insect has been found in some nurseries in Germany and Austria.

Natural origin of H. festerianusHypogeococcus festerianus was first described in 1942 by as Pedronia festeriana Lizer and Trellers who gathered in Argentina, near Mendoza on Cereus aethiops Haw.

In March 1972 the insect was picked up again by Dr. H. ZIMMERMANN and Dr. FD BENNETT of tge Commonwealth Institute of Biological Control on branches of Harrisia (Eriocereus) martinii in Argen-tina, Prov. Formosa, and sent to Dr. Williams of the British Museum (Natural History) in London, who arranged to study it and rename it as Hypogeococ-cus festerianus. The same author in the determi-nation of the new combination in 1973 glimpsed the possibility of use of such insect as biological control against some species of Cactaceae that be-come weeds, as Hypogeococcus seemed parasitize only some genera of this family.

In particular, the damage caused by this para-site on Harrisia martinii in nature are summed so (McFayden, 1979): H. festerianus not cause imme-diate damage to the tissues of the host plant even when present in dense colonies, while the deve-lopment of the branches whose apexes are infested

is blocked or distorted.Laboratory studies has shown that the growth

of the plant infested be blocked only at the point where the insect is present. If there is only one individual on the apex of a branch its growth is in-terrupted unilaterally, for which the branch curve at that point. If an entire colony settles on the apex of the same branch the growth is blocked completely.

The observations of Dr. BENNETT relate to other local species of cacti infested by this insect such Cleistocactus baumannii L. and Harrisia (Eriocereus) bonplandii Parm.

Following the insect was studied by McFayden of the Commonwealth Institute of Biological Control of Tucuman, Argentina, who found that the insect was specialized in the infestation of several species in the Cereaneae subtribe and planned a intervention of biological control on the cactus Harrisia martinii Lab. in Queensland, Australia by introducing Hypo-geococcus festerianus. This project was approved and the liberation of the insect was performed on a

Lobivia aff. pentlandii used in the proof of infestation shortly before his death. Hypogeococcus was maintained for the first year only on the mass of propagules side, while in the second year also came on the tips of others shoots already on the plant and the vegetative apex of the same.

This Cleistocactus margaretanus presents an infestation to about 2/3 of its height. When the plant was purchased the stem was still growing, but the presence of the parasite has blocked its normal distention at the point of infestation to which the axis is curved conspicuously. Following H. festerianus infested even the apex of the plant completely blocking its growth.


massive scale in 1974. At that time Hypogeococcus had been reported on Cleistocactus smaragdiflorus Web., C. aethiops Haw., Monvillea spegazzinii Web., M. sp. in various parts of Argentina (the provinces of Chaco, Formosa, Mendoza and Tucuman) and in the Chaco of Paraguay (McFayden, 1979).

Observations in the field have not shown the pre-sence of other cacti spread in his ark of natural distribution, such as the various species of Opuntia and even less on other plant species not cacti.

From careful laboratory tests it was found instead that the insect can lead life, even if short, on a por-tulacacea, Portulaca oleracea L.; in this case have not been reported the deformations mentioned for Eriocereus martinii and females are much less pro-ductive.

In nature Hypogeococcus is looted from various insects, such as the following wasps that attack immature females: Anagyrus sp., Anagyrtis sp. nr. pseudococci (Girault), Signiphora sp. and two un-determined Encirtides; by Coleoptera Coccinellidae Hyperaspidius trimaculatus (L.), Diomus sp. and Dip-tera Cecidomide Kalodiplosis floridiana Felt. Labora-

tory studies have shown that a colony of Hypoge-ococcus festerianus although preyed upon by one of indeterminate encirtides continued to grow un-til the entire plant was covered with insects. Best result showed the use of cecidomide K. floridiana which quickly extinguished H. festerianus.

Recognition of cochinealCollecting mature specimens of Hypogeococcus and normal woolly mealy bugs and immersing them in alcohol in a glass tube is possible to distinguish some differences with the naked eye. Normal mealy bug is generally more voluminous and gray just pale rose. The species we deal instead is pink to reddish vinous and remains small in size. Moreover, the be-havior of the two species are different, as the nor-mal cochineal settles especially in depressions of a plant, such as the slots between the ribs, between the tubercles, the base of the fruit or at the point of contact of two neighboring plants. The defor-ming cochineal instead is localized on the areolae of all Cactaceae, and those present along the stem but especially at the apex of the plants because the

Two young plants of Cereus peruvianus infested simultaneously. The specimen highest suffered an attack while the second plant apical side. The stem of the two plants is presented bend at the base, probably not related to the presence of the insect infestation before but because the pot was not placed on a floor. Following infestation plants no longer have shown the ability to return to the upright position. The second plant later suffered an attack of rot developed between proliferation that caused the death.


young nymphs are characterized by positive photo-tropism (move toward light) and negative geotropi-sm (move upwards). The genus name refers to the behavior of other species (Hypogeococcus barbarae Rau, H. othnius Miller & McKenzie, H. spinosus Fer-ris) who prefer to infest the apparatus underground plant. The production of shoots takes place in the same areolas object of infestation, and after the proliferation, the insect migrates within the mass of shoots to find protection.

The insect, such as the common mealy bug win-ters in colonies protected by small woolly cocoons not necessarily on the plant; indeed it is possible to find these cocoons under the pots, on pallets in a shaded or soil if undertaken gravels porous like lava red, in which the insect lurks inside the crevices. The casing that protects Hypogeococcus was found to be much more robust and consistency almost pa-per, presumably effective protection that nullifies the action of pesticides.

In the laboratory, the insect has presented three neanidal ages in females and 4 males. Furthermore it was observed as adults are able to move actively in search of new sites (in contrast to what happens in the other scale insects). The eggs are laid for a period ranging from one month to year-round if heated greenhouse. Are laid 24 eggs a day, which

in favorable conditions (20-30 ° C) hatch after 20 minutes; in dissected mature females were counted 80-100 eggs. Females produce protective wax in which, if it were made possible by external causes, remain hidden throughout their lives; males moving in the outer parts of proliferations, where they spin cylindrical whitish small shelters where they remain to spend the last post-embryonic period before be-coming adults.

The juvenile phase is completed in 28-30 days, the lives of adults is about 60 days to 10 days for the female and the male. In cold weather the insect does not go into stasis (diapause) but continues to develop, although slowed.

The study of the insectIn the summer of 1991 we personally found an infe-station of remarkable proportions in a large succu-lents nursery. So it was that we found an opportu-nity to deepen our knowledge of this parasite. One of infested plants was purchased and placed under observation in isolation. Meanwhile we arranged to extend the research on the presence of this insect in other nurseries. The same year it was decided to conduct a study on the insect, which is reported here.

In the summer of 1992, we again went to the nursery above to acquire other specimens of cac-ti of different genera to assess any differences in morphogenetic alterations. In autumn 1992 by these populations of cochineal we got male spe-cimens. We tried to determine the species of the insect and thus we became aware of the fact that the scale insect had already been the subject of stu-dy by Dr. S. MAROTTA and A.P. GARONNA University of Potenza since 1988 and reported in Italy since 1986 in greenhouses on the Italian Riviera (SUSS & TREMATERRA, cit. By MAROTTA, 1991) with the name Hypogeococcus festerianus. The Same MAROT-TA has subsequently verified the likely belonging to the species of the insect Hypogeococcus pungens (Granara) (Marotta, pers. Comm.). Followed exchan-ges of material and information with Dr. MAROTTA which allowed us to verify the conclusions obtained from our observations.

Aim of the studyThe purpose of this study was to evaluate the real responsibility for Hypogeococcus fesierianus (Lyzer & Trellers) in alterations of morphogenesis and development observed in specimens of Cactaceae haunted by it. In addition, to compare the extent and type of deformation that causes the same in-

Branches of × Epiphyllum. The insect is protected within the convolutions of the stem.


sect species in Cactaceae very distant both phyloge-netic both in their distribution.

MaterialsFor evidence of infestation, a small population of the cochineal was obtained through the purchase of a portion of an infested cactus species Backe-bergia militaris in summer of 1991. The plant was presented with a slight alteration, consisting in the formation of a head of five branches and resulted in only slightly infested areolas baseline.

A specimen of Lobivia (L. aff. pentlandii Britton & Rose) was used as the first guest.

The breeding of the parasite was carried out in heated greenhouse with temperatures at night win-ter of +7 ° C.

For comments on the alterations inflicted on va-rious species of cacti, a group of plants of diffe-rent species were purchased in 1992 from the same nursery. The state of morphological alteration in these specimens was already advanced. The species affected by these observations were: Cleistocactus margaretanus, Pilosocereus palmeri (Rose) Byl & Rowley, Espostoa lanata (HBK) Br. & Rose, Cereus peruvianus (L.) Mill., Melocactus sp., Ferocactus wi-slizenii (Eng.) Br. & Rose, Lobivia pentlandii (Hook.) Br. & Rose, Gymnocalycium baldianum (Speg.) Speg., Astrophytum myriostigma L. Leuchtenbergia principis Hook., Mammillaria aff. scrippsiana Br. & Rose.

A plant of × Epiphyllum sp. was haunted by ac-cident from the first colony of H. festerianus grown in the greenhouse; Also this specimen was added to the previous.

MethodEvidence of infestation: the group of Backebergia militaris was divided and the five portions were grafted on as many Myrtillocactus geometrizans. A portion of the infested plant has been preserved separately while the five grafts were treated repea-tedly with different insecticides, until the cochineal has not been completely eliminated.

Scale insects preserved by the treatment have been used to infest another cactus, Lobivia pent-landii. To this end it was followed by two methods:1. Direct transport of adults over the host of the

cochineal, at various points of the same.2. Through direct positioning of the portion of in-

fested plant on guest.Observations on the plant infested Lobivia pent-

landii have followed continuously for the following two years, until the death of the same.

Results of observations

Evidence of infestationThe plants of Backebergia militaris grafted, fol-lowing the disappearance of the total parasite are back to develop in the normal manner, without pro-liferation (the species is in fact characterized by a development cereiforme up to a solitary old age, in which occurs the spontaneous production of bran-ches side, but which are never produced in large groups).

The first attempt of the infestation, which is to transport individuals adults on the plant gave nega-tive results and saw the scale insects perish before they could settle on the plant. The second method

On this Ferocactus wislizeni the cochineal caused the production of sprouts in individual areoles next to the plant apex. Following one of the branches has developed a beginning of fasciation (crest).

In the case of this Melocactus applies the previous example; the growth of sprouts has closed the vegetative apex, which growth was alredy stopped for some time and which houses a large colony of insects.


has yielded positive results leading to the infesta-tion of the host plant following the spontaneous migration of the parasite from the portion of infe-sted plant in dehydration and the guest.

The infestation is determined by the migration of pests in particular points of the host plant, which consists wholly in the areolas, the base of the spi-ne. Areolae infested preference were found to be both those positioned at a height of about 2/3 of the plant, and those around the apex of the same.

The infestation, determined in the summer months was followed immediately by a morphologi-cal alteration in the development of the host plant, consisting in the immediate proliferation of a side branch of the normal plant.

In the following period were observed the fol-lowing phenomena:

Each areola at the apex of this branch has produ-ced a new secondary bud. Each of these sub-bran-ches, just come to differentiate the areolas again has proliferated in tertiary ramifications.

Some secondary and tertiary branches have chan-ged into flowers.

The base of infested branch has developed a den-se mass of adventitious roots.

The activity of growth was apparently slowed the entry into the host plant dormant during the winter. The temperature at which the plant was maintained was night from a minimum of +5 °C to a maximum of +10 °C in the coldest period. Occasionally the temperature had sags up to 5 °C (three days, con-secutively).

The spring vegetative growth was followed by the recovery of the modification of the plant affected by the morphogenetic infestation and intense proli-feration of the parasite that later migrated to other parts of the plant, such as the vegetative apex of a second branch normal and the apex vegetative main plant.

At the end of August the infestation has been accompanied by rotting that resulted in the death of the whole plant.

Comparisons between infestations of different plant speciesHildewinteria, Pilosocereus, Espostoa, Cereus - mas-sive development of buds at the apex of the plant or along the stem generally in the upper half of the same, usually followed by the distortion of the branch at the point of infestation.

When infestation commonly develops a single large mass of shoots which are protecting the fema-les; secondarily from that core infestation spread

the nymphs that can originate new nuclei of in-festation or remain on the main mass of shoots. Often this mass undergoes degeneration, it will de-velop outbreaks of rot that spread also to the main branch.

Melocactus, Ferocactus - are usually attacked the areolas at the vegetative apex; thereupon, su-periorly to the plugs and simultaneously in each

Specimen of Espostoa ritteri infested by the mealy bug in a European nursery. Among the proliferations has developed a crested branch.

Infestation of H. festerianus on Melocactus matanzanus.


areola, develop sprouts single or multiple youthful appearance, the vegetative apex of the latter are secondarily infected, and in turn give rise to se-condary branches, etc. Sometimes the branches give fasciation (crests).

Lobivia, Gymnocalycium, Astrophytum - are at-tacked all the areolas and the development of se-condary proliferations can occur at any level of the plant, but generally the proliferation remains nu-merically lower. Often initially differentiated flower buds (equipped with scales basal) differ trunk or vice versa. When the final development ends in flo-wer it is considerably reduced in size. Were not seen the fruits of these plants.

Many specimens of Astrophytum myriostigma in-fested were offered on the market from various mer-chants, often bearing even the insect. The journal of the German association of amateur was published a photo of one of these plants, but where it is pre-sented as a particular variety (GRUNERT H., 1990).

Leuchtenbergia - The infestation occurs primarily at the apex of the tubercles and is followed by the production of sprouts, one to many (at least 5).

The plants proliferating were offered on the mar-ket by some traders as particular varieties.

Mammillaria - Probably the most horrifying exam-ple of morphological alteration.

In the present case mammillaria observed, proba-bly Mammillaria scrippsiana, was noted only at the level of the infestation areolas axillary tubercles, bearing fruit in the course of maturation. The plant has no proliferation at the level of areolas apical tu-bercles. The development of the fruits instead was strongly altered.

The fruits are resistant to the touch, strangely

deformed and bulky, but they retain the red color and the typical plumpness.

The section of a fruit made in August took over as observed in the plant the seeds have not fini-shed developing normally, but have been allowed to vegetate trophic strengthening relations with the mother plant and are developed completely in green seedlings. In the fall of many fruits have ended up tearing letting out the proliferation of shoots. The removal of a fruit has been made possible only with the use of a razor blade and was followed by a loss copious latex; the result was presented with the very swollen base. Several fruits that have not torn or that they torn in part shown the development of individual shoots, emerging directly from within floral residues. This phenomenon could be explai-ned easily if you were sitting in front of cacti as the oldest Opuntioideae in which fruits you can origi-nate new shoots. The Mammillarias as other kinds newer usually do not show such a primitive cha-racter; However, the example suggests that even in these plants is kept the presence of latent buds on

Longitudinal section of one of the fruits of mammillaria: in the center appear small masses of shoots differentiated from the initial seeds. Probably the seedlings derive their nourishment from the intensification of embryonic lymphatic vascular system, as it can be assumed by the presence of latex in the tissue of the fruit itself. Pictured is best highlighted the development of a seedling apex of the fruit, in the center of the floral residues.


fruit, even if only a strong stimulation such as that produced by H. festerianus can stimulate them.

Epiphyllum - The infested plant, a hybrid Epiphyl-lum, presented infestations especially on apical buds and those at the base of the stem. They obser-ved two behaviors:1. When attacked the apical buds the stem grows

strongly curving its axis, so that it forms a tight inner curve in which lurks the cochineal.

2. When the buds are infested basal forms an axis very shortened and strongly proliferating shoots always directed downwards. The cochineal is lo-calized below this formation.

ConclusionsIn conclusion, based on the observations reported and the inspections obtained from the publications consulted is believed that the parasite studied is the direct cause of the deformities caused on host plants. Any other factor that may be considered se-condary conveyed dall’insetto in host plants to de-termine the observed malformations, such as bacte-ria or viruses, it is considered unlikely.

Cochineal in question is not the only parasite that causes deformations in the plant that attacks. Some aphids (Eriosoma lanigerum) determine these disorders, while others (Diptera, Hymenoptera and Hemiptera) are able to cause the plant producing galls with regular shapes that serve as the insect to lay the eggs.

The phenomenon is caused by the production by the parasite for a particular substance (probably an enzyme) that is injected into the plant together with the salivary fluids. This substance interacts with the tissues of the plant, causing an abnormal production of regulatory substances or disorganized growth that subsequently determine alterations in the normal morphogenetic processes.

Alterations inflicted by H. festerianus we obser-ved are varied:1. Spatial development of the stem: the stem of

the plants of columnar or sliding, it is thin up to 0.51 cm (Epiphyllum) both with a diameter of 5 cm (Cleistocactus) presents growth arrest in point of infestation that causes the twist of axis until it assumed spiral shape.

2. Production of sprouts: secondarily to the block of development in columnar plants or directly in spherical plants the first engagement point from place to the production of shoots in large num-bers; sprouts have juvenile characters (bristly spines). Following this phenomenon can arise crests. Voluminous masses of shoots can also

develop abundant formations of adventitious roots at their base.

3. Modification of the differentiation of the gems in development: especially for species globular buds appearing already well differentiated flo-wer secondarily differ stem and vice versa.

4. Alterations of the fruit: the presence of H. fe-sterianus at the base of the fruits of Mammil-laria led to a sort of live birth, with induction to the vegetation of the seedlings during their embryonic stage. There has thus determined seed formation, but the development is con-tinued until the mixture secondarily seedlings emerging from the fruits after tearing the same and contracting trophic relationships with the mother plant.

5. Stunted growth: all plants in which we obser-ved the infestation of the vegetative showed the complete closure of the development of the same axis, the consequence of which seems to be a more boost production of side shoots.

Other species of plants grown attached dall’inset-to and reported in the bibliography consulted (Suss, TREMATERRA, 1986) are: Espostoa melanostele Vpl., E. ritteri Buin., Echinopsis sp., Parody sp., Notocac-tus leninghausii Haage Jr., Weberbauerocereus win-terianus Ritter.

Tips for controlling Hypogeococcus festerianus

GeneralThe first action to be taken to limit the spread of the insect would be to limit the introduction by the refusal of plants imported from abroad on which we note the heavily presence of the insect.

The treatments to be made for its removal should provide the flaring of the plants, the elimination of the shoots or to reduce them to allow the display of any colonies or individuals in order to make them hidden then treatments anticoccidials on the whole plant. The potting soil should be kept separate from the cultivation, treated with chemicals or incine-rated if made of peat, never reused as such. If the colonies are already present on these pots should be removed or thoroughly disinfected before reuse.

It is important to act immediately as the ability to proliferate is very high and the nymphs in mi-gration have reduced dimensions so easily escape observation.

Generally it is not recommended to continue the cultivation of seedlings on a pallet.

The new seedlings, so healthy, are kept isolated


from the infested material that is to be gradual-ly eliminated by avoiding its distribution with the sale.

Heavy infestations that occur in specialized nur-series are very difficult to control and can be more cost-effective destruction by incineration, com-pletely avoiding their spread in soils, rivers or any other open environment, as it is not clear whether this species has a chance to adapt to parasitize other plants while it is determined that resists tem-peratures of our climates.

The chemical controlThe pest that seems to have given the best results was the one conducted with the use of Aldicarb granular formulation to 4.75% of active substance (as), distributing approximately 3.54 g / m2 and para-pellets with a dose of about 5.7 g to 5450 cm3 of air (within a bell jar) and Dimethoate for a period of one week. These treatments have been effective for most individuals protected.

The use of D.D.V.P. and white mineral oil (80%) of 2% with cypermethrin (10%) to 0.1% was effec-tive only on nymphs exposed (SÜSS, TREMATERRA, 1986).

Biological controlVarious species of insects prey on H. festerianus in South America, as mentioned previously. At this point, however, one may wonder whether the in-troduction of new predators to control this pest is a practice reliable or whether it does not agree to consider that the insect comes naturally plundered by others already on our territory. Among the pests available you can groped fight with Anagyrus sp. nr. pseudococci (Girault).

The use of H. festerianus in the practice of vegetative propagation of cactiGiven the large capacity of this insect in inducing the production of myriad shoots think is immedia-te as the insect can be applied in the propagation of the species which are rare and poorly accestanti course. The attempt made by us to infest a copy of grafted Aztekiuni ritteri failed while there has been a slight infestation borne its rootstock, a Myrtillo-cactus geometrizans in October of 1992. In the case of Backebergia militaris, previously reported, the infestation has resulted in various seedlings from a single plant, which after thorough disinfection and graft have perfectly healthy specimens of this species in danger of extinction.

Other methods of vegetative propagation such as

grafting followed by shearing do not give a produc-tion so rapid and high. It is necessary to control the parasite in a careful, to prevent its migration on the single main seedling and to contain the de-velopment.

The danger of the insect against the other plants in culture should be considered carefully when you decide to raise it for purposes related to the one above; in particular it should be very well isolation of the plants with water barriers, guards to prevent the transport of nymphs through the wind, the con-tact of the specimens with any other plant pests even short-term as well as the allocation albeit short of infested plants on shelves or trays in which are located or will be located other healthy plants.

Annex 1: other exotic insectsIn Italy have been reported many other species of cochineal from warm countries, probably not only associated with the import of succulent plants but also of exotic fruits; of the 14 mentioned here, at least 13 have been reported only for the region:

Fam. Pseudococcidae: Delottococcus euphorbiae (Ezzat & McConnell), Planococcus citri (Risso), Pseudococcus affinis (Maskell), Rhizoecus cacticans (Hambleton), Spilococcus mammillariae (Bouchè), Vryburgia rimariae Tranfaglia (often this species in-fests stapelie and mesembs); Fam. Coccoidae: Coc-cus hesperidium L., Pulvinariella mesembryanthemi (Vallot), Saissetia oleae (Olivier); Fam. Eriococci-dae: Eriococcus cactearum Leonardi, Ovalicoccus agavium (Douglas); Fam. Diaspididae: Diaspis echi-nocacii (Bouchè), Abgrallaspis cyanophylli (Signo-ret). Two species of the most recent reporting are Eriococcus coccineus (Cockerell) and Selenaspidus albus (McKenzie).

Final remarksThe draft biological control of McFayden (see pa-ragraph: Source Natural H. festerianus) is not the first to be applied on cacti pests in Australia; alrea-dy years before it was introduced in that country a moth, Cactoblastis cactorum (Berg) with the specific intent to limit the spread of a species of Opuntia first introduced and then got out of hand and be-come weeds. Then the experiment was a great suc-cess and is still considered the first experiment of biological successfully conducted in the history of farming practices, and often cited as an example.

In regard to Hypogeococcus festerianus, you can not recognize that its use has been followed by a remarkable success in the control of cactus host Harrisia martinii, however it is also clear that those


responsible for its spread outside of its range had no idea of ability to adapt to the many other insect species of cacti exist on the American continent, as they could not believe that the extent of marketing of cacti in the world is such that any country on earth can be passive subject import of this para-site, in first sight so similar to other insects less dangerous and already well known by the common collectors and growers succulent. It is hoped that on its way to the richer countries of species of cacti Hypogeococcus are many natural predators are able to limit its spread, otherwise in a few decades, its presence is paleserà sadly in most of the natural areas of spread of cacti in America.

AcknowledgementsI wish to thank Dr. POLLINI Observatory of plant diseases of Bologna, Prof. M. MARINI Institute of Zoology and Professor MAINI Institute of Agricultu-ral Entomology, both of the University of Bologna, for the help allotted in the procurement of library materials; also extend a special thanks to Dr. S. MA-ROTTA’s Dip. Biol. Defense and Biotechnology Agro-forestry Potenza for giving me the use of his publi-cations and his first-hand information and finally my friend Roberto MANGANI for his willingness to provide personal observations and documentary ma-terial.

BibliographyGRUNERT HERBERT (1990) «Interessan-

te Sprossbildung bei Astrophytum myriostig-ma». Kakt. and. Sukk, 41 (7); pp. 148149.

LONGO S., MAROTTA S., Russo A., TRANFAGLIA A. (1989) «Contributo alla conoscenza della cocci-dofauna (Hornoptera, Coccoidea) della Sicilia con la descrizione di una nuova specie». Entomologi-ca, XXIV Bari; pp. 163179

MAROTTA S., GARONNA P. (1991) « Homoptera Coc-coidea: nuovi e poco conosciuti parassiti delle piante grasse in Italia». Atti XVI Cong. naz. Ento-mol. BariMartina Franca; pp. 741746.

McFAYDEN R.E. (1979) «The cactus mealybug, Hypo-geococcus festerianus (Hem.: Pseudococcidae) an agent for the biological control of Eriocereus martinii (Cactaceae) in Australia» Entomophaga, 24 (3); pp. 281 287.

Suss L., TREMATERRA P. (1986) « Hypogeococcus festerianus (Lyzer & Trellers) (Homoptera; Coc-coidea) nocivo alle cactaceae ornamentali in Li-guria» Inf. Fit., 10; pp. 4346.

TRANFAGLIA A. (1981) «Studi sugli Homoptera Coccoidea» Boll. Lab. Ent. Agr. Portici, Napoli; pp. 328.

WILLIAMs D.J. (1973) «Two Cact us feeding Me-alybugs from Argentina (Hornoptera, Coccoidea, Pseudococcidae)» Bull. Ent. Res. 62; pp. 565570.

mq 3 - the super mealybug

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