starting a cassava farm starting a cassava farm

Braima James, John Yaninek, Ambe Tumanteh,Norbert Maroya, Alfred Dixon, Rasaq Salawu, Joseph Kwarteng

Startinga

Cassava Farm

Startinga

Cassava Farm

International Institute of Tropical Agriculture

About this booklet

This booklet is one in a set of field guides prepared by the International Insti-tute of Tropical Agriculture (IITA) to increase the technical knowledge of exten-sion agents and enhance the integration of plant protection and plant produc-tion practices in farmers’ efforts to grow a healthy crop of cassava. The bookletis based largely on the extension and farmer training experience of the regionalproject “Ecologically Sustainable Cassava Plant Protection” (ESCaPP), 1993–1997. ESCaPP was executed by IITA’s Plant Health Management Division(PHMD), in collaboration with national agricultural research and extension sys-tems in Bénin, Cameroon, Ghana, and Nigeria, and funded by the Division ofGlobal and Interregional Programmes of the United Nations DevelopmentProgramme (UNDP).IITA is one of 16 nonprofit international agricultural research and training cen-ters supported by the Consultative Group on International Agricultural Re-search (CGIAR). Their shared mission is the alleviation of hunger and poverty intropical developing countries by generating appropriate plant production andprotection technologies which benefit the poor and enhance agricultural pro-duction while preserving the natural resource base. At IITA, PHMD is dedicatedto sustainable plant protection of primary food crops in Africa. The division’sresearch philosophy is to identify and correct the ecological imbalances in agri-cultural systems causing pest problems and to provide environmentally andeconomically appropriate options for integrated pest management. (IPM)

For more information contact:The Director

IITA Plant Health Management DivisionBiological Control Center for Africa

08 B.P. 0932Cotonou, Republic of Bénin

Fax: (229) 35 05 56Tel: (229) 35 01 88

E-mail: [email protected] visit IITA’s website at: http://www.cgiar.org/iita

Starting a Cassava FarmIPM Field Guide for Extension Agents

Braima JamesInternational Institute of Tropical Agriculture, Plant Health Management Division,Cotonou, Bénin

John YaninekInternational Institute of Tropical Agriculture, Plant Health Management Division,Cotonou, Bénin

Ambe TumantehInstitut de Recherche Agronomique et du Développement, Ekona, Cameroon

Norbert MaroyaInstitut National des Recherches Agricoles du Bénin, Niaouli, Bénin

Rasaq SalawuOgun State Agricultural Development Project, Ogun State, Abeokuta, Nigeria

Alfred DixonInternational Institute of Tropical Agriculture, Crop Improvement Division, Ibadan,Nigeria

Joseph A. KwartengDepartment of Agricultural Economics and Extension, University of Cape Coast,Cape Coast, Ghana

Contents

What are the objectives of this guide? ------------------------------------------- 4

Introduction -------------------------------------------------------------------------- 4

How do I select a good site for planting cassava? ------------------------------ 6

How do I improve the soil for planting cassava? ------------------------------- 8

How do I select the best cassava varieties to plant? -------------------------- 10

How do I select healthy cassava stem cuttings? -------------------------------12

How do I best plant cassava? -----------------------------------------------------16

Summary ----------------------------------------------------------------------------- 19

5

IPM Field GuideStarting a Cassava Farm

4

What are the objectives of thisguide?

This field guide has been prepared to help youto:

• select good sites for cassava farms,• improve soils for good cassava growth,• select suitable cassava varieties for plant-

ing, and• select, prepare, and plant healthy cassava

stem cuttings.

Introduction

Cassava is one of the most common foodcrops grown and consumed in many parts ofAfrica. The crop grows well in various soiltypes and ecologies. It can be planted alone orin association with many other crops, likemaize, groundnuts, vegetables, and rice. Grow-ing cassava is not very labor intensive and usu-ally requires 75–125 person-days per hectarefrom land preparation to harvesting. The stor-age roots can be harvested 9–18 months afterplanting. Under traditional farming practices,one can expect between 8 and 15 tonnes ofstorage roots per hectare of land planted onlywith cassava. Even under harsh environmentalconditions cassava will provide some foodwhen other crops fail. In most places there is agood market for cassava. The storage rootscan be processed into various food products(Figures 1 and 2), and starch for domesticconsumption, local, and/or export markets.Cassava leaves are nutritious vegetables (Fig-ure 3). The leaves and storage roots can alsobe used as animal feed. The stems can be soldas planting material.

In order to grow a healthy crop of cassavayou will need to combine plant productionand plant protection practices. These includesite selection, soil improvement, variety andplanting material selection, and planting andpost-planting measures against weeds, pests,and diseases. The companion field guides on“Weed Control in Cassava Farms”, “Pest Con-trol in Cassava Farms”, and “Disease Controlin Cassava Farms” cover specific details ofweeds, pests and diseases.

Figure 2:Gari preparation

Figure 3:Good cassava leafharvest

Figure 1:Assortedcassava products

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6

Figure 4: Testing soil texture by the “feel”method

How do I select a good site forplanting cassava?

Cassava grows best in areas with deep andwell-drained loamy soils, adequate rainfall, andwarm and moist climatic conditions. The fac-tors which guide you to determine if an areawill be suitable for growing cassava include veg-etation cover, soil texture and fertility, topogra-phy of land, and the field history of the area.

Look for an area with thick vegetationcover: Sites with dense vegetation cover arelikely to have fertile soils. The dense vegetationshades the soil from direct sunlight, reducesthe amount of moisture that is lost from thesoil through evaporation, and minimizes run-offwater which may otherwise cause soil erosion.The dense vegetation also drops a lot of leaveswhich rot and add nutrients to the soil. In addi-tion, decaying leaves encourage an increase inthe number of earthworms and other small in-vertebrates in the soil, which in turn help toincrease the air in the soil and make it betterfor growing cassava.

Look for an area with good soil texture:The best soil for growing cassava is deep,loamy soil. Such soils are rich in nutrients, lowin gravel, hold water well, and are easy to workor till. The way to tell if the soil is loamy is tomoisten a small amount of it and try to shapeit into a ball (Figure 4). If you press the ball andit falls apart, then your soil is loamy. If it feelsgritty and you are not able to shape themoistened soil into a ball, then the soil issandy. If you shape the soil into a ball, and thesoil does not fall apart when pressed, then thesoil contains a lot of clay and is a clayey soil.Sandy and clayey soils are not the most suit-able soils for growing cassava.

Look for an area with fertile soil: Fertilesoils usually have a dark color, for example,dark red or dark brown. The dark color showsthat the soil has a lot of organic matter. If thesoil looks gray and sometimes contains greenor blue spots, it means that there is poordrainage and waterlogging. Do not grow cas-sava on soils that get waterlogged.

Look for an area with flat or gently slop-ing land: The best farmland for cassava is flator gently sloping. Steep slopes are easilyeroded and are therefore not very good areasfor growing cassava. Valleys and depression ar-eas are also not very suitable because theyusually get waterlogged and do not allow cas-sava roots to develop well. You may, however,plant early maturing cassava varieties onmounds or ridges in inland valleys during thedry season.

Know the history of the site: Informationsuch as how the land was previously used, andthe types of weeds, diseases, and pests in thearea, can help you in selecting a site for yourcassava farm. Such information can help youto avoid a site with problems or make goodplans for plant protection. Table 1 can be usedto summarize the agronomic and cassavaplant protection history of a site.

For site description, tick (+) appropriate boxes.For pests, diseases and weeds, indicate importance of the problem as:+ = not serious++ = serious+++ = very serious

Pests, diseases, and weeds

Table 1: Site description and history

Site description

Vegetation coverScantyDense natural fallowDense improved fallow

Soil textureSandyLoamyClayey

Soil fertilityPoorGood

Topography

FlatHilly/steep slopesDepression area

Previous cropCassavaYamSweetpotatoRiceMaizeSorghumCowpea/legumesOther (specify)

Cassava pests in the localityCassava green miteCassava mealybugVariegated grasshopperSpiraling whiteflyCassava root scaleTermitesWhite scale insectsVertebratesOther (specify)

Cassava diseases in the localityCassava mosaic diseaseCassava bacterial blightCassava anthracnose diseaseCassava bud necrosisRoot rotsLeaf spotsOther (specify)

Common weeds in the localitySpear grassBermuda grassGuinea grassFeathery pennisetumSedgesSiam weedGiant sensitive weedWild poinsettiaTridaxGoat weedParasitic weedsOther (specify)

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8

How do I improve the soil forplanting cassava?

If you do not select a good site for growingcassava you may have to spend a lot of time andmaterials to improve the soil. Cassava plants ongood soils grow vigorously and are able towithstand some damage by pests and diseases.The following are examples of cultural prac-tices you can use to improve soil properties.

Manure your farm: At land preparation, youcan add organic manure to the soil to increasesoil nutrients, improve soil structure, and im-prove the ability of the soil to hold water. Or-ganic manure can be in the form of green ma-nure or other dead plant or animal manure. Ingreen manuring, plant foliage (fresh leaves andyoung green stems) is ploughed into the soil.Green manure improves soil properties as thefoliage rots. Egusi melon and leguminous crops,for example, groundnuts and beans, makegood green manure. Inorganic fertilizers canalso be applied to increase soil fertility. Forexample, in southeast Nigeria, the recom-mended rate for NPK application is 400 kg.per hectare of land.

Prepare suitable seedbeds: Cassava fieldson hilly sites with steep slopes are frequentlyeroded. The erosion will be severe if the leafcanopy of cassava plants is not thick enough tocover the ground against rain splashes. Thishappens in young cassava farms and if the vari-eties have a tall and less branching habit (Figure5). If you cannot avoid growing cassava onsteep slopes you can grow cassava varietieswith early, low, and much branching habit (Fig-ure 6) to cover the ground quickly and prop-erly against rain erosion. You can also makeridges across the slopes and mulch the ridgesto reduce erosion.

Mulch cassava seedbeds: Mulching involvescovering the soil surface with plant materials.Mulching improves the fertility of the soil, in-creases the ability of the soil to hold sufficientwater for plant growth, and reduces erosionand weed problems. Mulching cassava seed-beds is especially valuable when growing cas-sava in dry areas and on slopes.

Mulching requires very large amounts of plantfoliage. Dead plant foliage can be used as“dead mulch”. Sources of good dead mulchare foliage from alley crops, leguminous plants,rice husk, coffee hull and general crop andweed residues. Avoid using weed residuescontaining weed seeds, rhizomes, stolons, ortubers as mulch because these can increaseweed problems on your farm. Straws of maizeand guinea grass (Figure 7) are bad mulch ma-terials because they take too long to rot anduse up soil nitrogen as they do so.

You can grow plants as “live mulches”. For ex-ample, egusi melon (a food crop) planted atvery close spacing on cassava seedbeds is agood live mulch. Nonfood crops can also beused as live mulches, but these are normallygrown as improved fallow plants. For example,during fallow periods you can grow Mucunapruriens var. utilis on land you have selected forgrowing cassava in the next season (Figure 8).Mucuna pruriens var. utilis is, however, a fire haz-ard in the dry season when its foliage dries.

Plant cassava in association with othercrops: Appropriate intercrops improve soilproperties in a manner similar to live mulches.Crops that are commonly intercropped withcassava are maize, rice, legumes, and veg-etables. Legumes, for example, cowpea andgroundnuts, are a particularly good intercropbecause these plants make and release nutri-ents into the soil.

Figure 7: Shoots of guinea grass,Panicum maximum

Figure 6: Cassava variety with early, low, andmuch branching habit

Figure 5: Cassava variety with late,high, and less branching habit

Figure 8: Live mulch of Mucuna on fallow land

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How do I select the bestcassava varieties to plant?

The best cassava varieties are those that areliked by consumers, grow fast, give good yields,store well in the soil and are tolerant to majorpests, and diseases. The particular variety cho-sen by a farmer depends on her/his objectivesfor planting the crop, and the factors lookedfor in selecting cassava varieties usually in-clude the following.

Look for varieties with high dry matterand good food quality: Cassava storageroots consist mainly of water and dry matter.The dry matter is mainly starch and a little bitof fiber. The percentage of dry matter in theroots determines the quantity and quality ofthe products obtained after the roots areprocessed. Cassava varieties whose storageroots have 30% or more dry matter are saidto have high dry matter content. Such variet-ies produce good quality products and areprofitable for growers and market women.

Look for varieties with good mealiness:Mealiness refers to the cooking ability of cassavastorage roots without processing. Mealy variet-ies are commonly called “sweet” cassava whilstnon-mealy varieties are called “bitter” cassava.Bitter cassava requires processing before con-sumption and this is related to the total cyanidecontent (referred to as cyanogenic potential,CNP) in the storage roots. The higher the CNPof a variety, the greater the need to process itsstorage roots for safe consumption. If cassavaleaves will be eaten, you can also consider thecooking quality of the leaves.

Look for varieties that bulk early: Bulkingrefers to the swelling of the storage roots asthey are filled with stored food. Varieties thatbulk early are better able to offset losses instorage root yield caused by weed competi-tion, leaf-feeding pests, and disease than latematuring varieties.

Look for varieties with good groundstorability: Ground storability is the abilityof the mature cassava storage roots to stay inthe ground for a long time without gettingspoiled. Good ground storability prolongs theperiod over which the crop can be harvested.This reduces the duration of postharveststorage problems of fresh roots.

Look for varieties that are tolerant toweeds, pests, and diseases: Some cassavavarieties tolerate weeds, pests, and diseasesbetter than others. In selecting a variety togrow, it is advisable to consider how well thevariety can compete with weeds, and resistpests and diseases. For example, if weeds are aproblem you can look for adapted varietieswhich branch early, low, and often (Figure 6).Such varieties are able to develop a lot ofbranches and leaves quickly to shade theground and prevent weeds from growing vig-orously and becoming a problem. You can alsofind out if the variety has other features youmay want.

Table 2 lists some features of cassava varietiescommonly grown in West and Central Africa.Scientists and extension agents can prepare alist similar to Table 2 for the cassava varietiesgrowing in the locality.

Varie

tyE

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nce

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GM

Tole

ranc

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CM

DTo

lera

nce

toC

BB

IITA

IITA

IITA

IITA

TMS

4(2

)142

5H

igh

Hig

hLo

wG

ood

Goo

dM

oder

ate

Mod

erat

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ood

TMS

305

72H

igh

Hig

hM

oder

ate

Mod

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ood

Mod

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ood

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d

Ben

inB

enin

Ben

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BE

N 8

6052

Hig

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Poo

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895

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Cam

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Cam

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Hig

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Mod

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Mod

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8034

Hig

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Mod

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Gha

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Hig

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"Ab

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Hig

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Nig

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Nig

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MS

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NR

808

2H

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Hig

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Goo

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Tabl

e 2:

So

me

feat

ures

of

com

mo

n ca

ssav

a va

riet

ies

in W

est

and

Cen

tral

Afr

ica

Sour

ce: I

ITA

, IN

RA

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SD G

hana

, IR

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-Cam

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n, a

nd N

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iger

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13


12

How do I select healthy cassavastem cuttings?

The most common sources of cassava stemplanting material are farmers’ own farms. Oc-casionally, cassava stem cuttings are sold at vil-lage and town markets. Researchers and ex-tension agents sometimes provide their con-tact farmers with cassava stem cuttings. Manycassava pests and diseases are stem-borneand spread by distribution, sale, and planting ofinfested or diseased stem cuttings. By plantinghealthy stem cuttings, you can greatly reducethe spread and damage caused by these cas-sava pests and diseases. The following guide-lines will assist you to avoid unhealthy stemcuttings and to select healthy planting materialfor a healthy crop of cassava.

Look for healthy cassava plants: Selecthealthy cassava plants in the farm. Healthy cas-sava plants have robust stems and branches,lush foliage, and minimal stem and leaf damageby pests and diseases. From each plant selectthe middle brown-skinned portions of stemsas stem cuttings. These parts sprout and en-sure plant vigor better than the top greenstem portions. Stem cuttings taken from thetop green portions of stems or extreme topand bottom of stored stems are unsuitable.They will dehydrate quickly, produce un-healthy sprouts, and are easily damaged bypests and diseases.

Avoid plants with pests and diseases: Inselecting cassava plants as sources of stemcuttings, you should avoid those infected withthese pests and diseases. The common stem-borne cassava pests and diseases are cassavamealybug, cassava green mite, spiraling white-fly, white scale insect, cassava mosaic disease,

cassava bacterial blight, cassava anthracnosedisease, and cassava bud necrosis.

The cassava mealybug, Phenacoccus mani-hoti, occurs on cassava leaves, shoot tips, peti-oles, and stems. The mealybugs are coveredwith white waxy secretions. Cassava mealy-bug damage symptoms include shortened in-ternode lengths, compression of terminalleaves together into “bunchy tops” (Figure 9),distortion of stem portions, defoliation, and“candlestick” appearance of shoot tip. The in-sects survive on cassava stems and leaves andare easily carried to new fields in this way.

The cassava green mite, Mononychellustanajoa, occurs on the undersurfaces of youngleaves, green stems, and axilliary buds of cas-sava. The mites appear as yellowish greenspecks to the naked eye. Mites survive on cas-sava stems and leaves and are easily carried tonew fields in this way. Cassava green mitedamage symptoms include yellow chloroticleaf spots (like pin pricks) on the upper leafsurfaces, narrowed and smaller leaves (Figure10), “candlestick” appearance of the shoot tip,and stunted cassava plants.

The spiraling whitefly, Aleurodicus dispersus,damages cassava by sucking sap from the leaves.Colonies of the insect occur on the under-surfaces of cassava leaves and are covered withwhite waxy secretions similar to those of thecassava mealybug. Spiraling whitefly eggs occurin spiral patterns of wax tracks, mostly on theundersurfaces of leaves. Symptoms of whiteflydamage are black sooty mold on the upper leafsurfaces, petioles, and stems (Figure 11), andpremature leaf fall of older leaves. The insectssurvive on cassava leaves and stems and areeasily carried to new fields in this way.

Figure 10: Cassava shoot tip withsmall and narrow leaves caused bycassava green mite

Figure 9: Cassava shoot tip with“bunchy top” caused by cassavamealybug

Figure 11: Cassava stem and leavesblackened under attack by spiralingwhitefly

Figure 12: Cassava white scale oncassava stem

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14

The white scale, Aonidomytilus albus, coverscassava stem surfaces with conspicuous whitewaxy secretions (Figure 12). The insect suckssap from the stem and dehydrates it. Stemcuttings derived from affected stem portionsnormally do not sprout. The insects surviveon cassava stems and leaf petioles and are eas-ily carried to new fields in this way.

Cassava mosaic disease is caused by a vi-rus which occurs inside cassava stems. Symp-toms of cassava mosaic disease damage arepatches of normal green leaf color mixed withlight green and yellow chlorotic areas in amosaic pattern (Figure 13). Generally, plantswith these symptoms should be avoided assources of stem planting material. However,the disease is very common in Africa and it issometimes difficult to find cassava plants thatare completely free from the disease. You can,however, reduce cassava mosaic disease prob-lems by selecting stem cuttings from cassavastem branches and not from the main stems.Stem cuttings from the branches are morelikely to sprout into disease-free plants thanstem cuttings from the main stems.

Cassava bacterial blight is caused by a bac-terium which occurs inside cassava stems. Thedisease damage symptoms are angular leafspots on the under leaf surfaces, leaf blightingand wilting (Figure 14), gum exudate on thestems, and shoot tip die-back. Avoid selectingstem cuttings from plants with these symp-toms.

Cassava anthracnose disease is caused bya fungus which occurs on the surface of cas-sava stems. The disease damage symptoms arecankers (“sores”) on the stem and bases ofleaf petioles (Figure 15). The disease reducesthe sprouting ability of stem cuttings.

Cassava bud necrosis is caused by a funguswhich grows on the surface of cassava stemscovering the axilliary buds or the “eyes” ofstem cuttings (Figure 16). The affected budsdie, and the sprouting ability of stem cuttingsis reduced.

Figure 13: Cassava plant with cassavamosaic disease

Figure 15: Cankers of cassavaanthracnose disease on stem

Figure 14: Leaf blighting and wiltingcaused by cassava bacterial blight

Figure 16: Fungal patch (arrow) ofbud necrosis disease

p

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16

How do I best plant cassava?

The important factors to consider whenplanting cassava are time of year, land tillagemethods, seedbed type and preparation, andpreparation, handling, and planting mode ofstem cuttings.

Select suitable planting dates: You shouldtry to plant cassava early, at the beginning ofthe rainy season. This ensures healthy sprout-ing and good crop establishment which helpsthe plant to better withstand damage by dryseason pests like the cassava green mite, cas-sava mealybug, and termites. Late planting atthe end of wet season exposes the crop tosevere damage by these pests as the dry sea-son progresses. However, planting date rec-ommendations should fit within local farmingcalendars and farmers’ choice of crops to en-hance their adoption.

Use suitable land and seedbed prepara-tion methods: In cassava cultivation, land isusually tilled to loosen up the soil, improvesoil drainage, make it easy for roots to de-velop, and promote healthier storage root de-velopment. Mounds and ridges are commonlymade to gather top soil material for cassavaroot development, limit prolonged contactbetween the storage roots and stagnant wa-ter, and protect storage roots from rodentand bird pests.

The soil texture at the site you select for cas-sava cultivation will be an important factor indetermining the level of tillage and type ofseedbeds required for your cassava farm. Indeep loamy soils, tillage may be essential but itdoes not matter which seedbed type isadopted and cassava can be planted on the flat

(Figure 17), mounds (Figure 18), or ridges (Fig-ure 19).

However, if the loamy soil is shallow and cas-sava is planted on the flat, the storage rootswill quickly reach hard ground or rocks givingpoor yields. In sandy soils, minimum tillage andplanting cassava on the flat are appropriatebecause the soil is sufficiently loose to allowfor faster drainage and normal storage rootdevelopment. At sites where the sandy soilgets waterlogged, it is however better to makeridges or mounds than to plant on the flat. Inclayey and poorly drained soils, tillage andplanting of cassava on mounds or ridges arealso essential to limit the effects of waterlog-ging.

Prepare and handle stem cuttings prop-erly: When cutting up cassava stems intostem cuttings for planting, make sure eachcutting is at least 20–25 cm long and has ab-out 5–8 nodes. You should handle cuttingscarefully during transportation to preventbruises and damage to the nodes. This can bedone by packing them on cushions of dryleaves.

Sometimes, when planting material is slightlyinfested with cassava green mites, cassavamealybugs, and other stem-borne pests, thestem cuttings can be treated by immersingthem in heated water for 5–10 minutes justbefore planting. This treatment will kill pestson the surface of the cuttings. You can preparethe heated water by mixing equal volumes ofboiling and cold water. Alternatively, you candip the stem cuttings into a dilute pesticidesolution (for example, 1% Rogor solution) tokill stem-borne pests. You can also reduce theincidence of cassava anthracnose and other

Figure 18:Cassava growing

on mounds

Figure 19:Cassava growingon ridges

Figure 17:Plantingcassava onthe flat

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18

stem-borne fungal diseases if a solution ofpesticide (for example, Décis) and fungicide(for example, Benlate) is used. If pesticides areto be used, you should consult the label forguidelines on their application methods andhow to avoid personal and environmental haz-ards associated with their use.

Adopt suitable planting mode: In orderto get the best sprouting and growth fromcassava stem cuttings, it is important to plantthem properly. Cassava stem cuttings may beplanted vertically, at an angle, or horizontally.When planted vertically, the storage rootsdevelop deeper in the soil, more closely to-gether, and are more difficult to harvest bypulling. Vertical planting is best in sandy soils.In such soils, plant stem cuttings verticallywith 2/3 of the length of the cutting belowthe soil. When planted horizontally, the stor-age roots develop more closely to the sur-face and are more likely to be exposed andattacked by rodent and birds. Also, in hori-zontal planting several weak stems developfrom the stem cutting. Horizontal planting,however, has the advantage of killing insectand mite pests which occur on the surface ofstem cuttings. In loamy soil it is probably bestto plant at an angle.

The spacing between plants will depend onwhether you are growing cassava alone (solecrop) or with other crops (intercropping). Ifcassava is being grown alone, plant 1 meterapart from each other. If cassava is beinggrown as an intercrop, consider the branchinghabit of both the cassava and the other cropsand make sure there is enough space for theplants. You should also make sure there isenough space for you to work between theplants during weeding and other activities.

Summary

• To select a good site for a cassava farm, look for an area with dense vegetationcover, good soil texture, fertile soils, and flat or gently sloping land; also examine thefield history to plan for plant protection measures.

• Improve the soil by manuring, mulching, and intercropping to encourage cassavaplants to grow vigorously and offset damage by cassava diseases.

• To select good cassava varieties for planting, look for varieties with high dry matter,good mealiness, good ground storability and which are well adapted to your area;the variety should also bulk early and be easy to process.

• To select healthy cassava stem cuttings, choose healthy cassava plants as sources ofplanting materials; use stem cuttings taken from the middle, brown portions of thestem and free of stem-borne pests and diseases.

• To prepare cassava stem cuttings for planting, cut each stem cutting to a length ofat least 20–25 cm; use stem cuttings with about 5–8 nodes; treat stem cuttingsslightly infested with stem-borne pests by immersing them in heated water for 5–10 minutes, dipping them into a dilute pesticide solution, or by planting them hori-zontally.

• To plant cassava stem cuttings properly consider the type of soil; prepare ridgesand mounds in areas where soil gets waterlogged; use minimum tillage in sandy soil;plant cassava stem cuttings vertically in sandy soil; plant cassava stem cuttings at anangle in loamy soil; plant cassava stem cuttings 1 meter apart from each other insole cropping; and in cassava intercrops make sure there is enough space for theplants.

Starting a Cassava Farm

20

Acknowledgements

Special thanks to the United Nations Development Programme and the Austrian governmentwhich provided funds, and to the following institutions which provided materials, information andservices for the production of the set of cassava IPM field guides:

• Agricultural Development Programmes (ADPs) in Abia, Akwa Ibom, Anambra,Benue, Cross Rivers, Rivers, Delta, Edo, Enugu, Imo, Kogi, Kwara, Ogun, Ondo, Osun,Oyo, and Plateau State Governments, Nigeria

• Centre d’Action Régionale pour le Développement Rural (CARDER), Bénin

• Centro International de Agricultura Tropical (CIAT), Cali, Colombia

• Crop Services Department (CSD), Department of Agricultural Extension Services(DAES), and Plant Protection and Regulatory Services Department (PPRSD), Minis-try of Food and Agriculture, Ghana

• Federal University of Technology, Owerri, Nigeria

• Fourah Bay College, University of Sierra Leone, Freetown, Sierra Leone

• IITA Eastern and Southern African Regional Centre (ESARC), Uganda

• Institut de Recherche Agronomique et du Développement (IRAD), Cameroon

• Institut National de Recherche Agronomique du Bénin (INRAB), Bénin

• National Root Crops Research Institute (NRCRI), Umudike, Nigeria,

• Rural Training Centre (RTC, Presbyterian Church) in Fonta and Kumba, Cameroon

• Sasakawa Global 2000, Bénin

• Service de Protection des Végétaux et du Contrôle Phytosanitaire (SPVC), Bénin

• Southern African Root Crops Research network (SARRNET), Malawi

• University of Agriculture, Abeokuta, Nigeria

• University of Buea, Buea, Cameroon

• University of Cape Coast, Cape Coast, Ghana

starting a cassava farm starting a cassava farm

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