DEPARTMENT: AGRICULTURE

EditorDR A.J. LIEBENBERG

Dry beanproductionDry beanproduction

2002

Compiled by Directorate Agricultural Information Services, Department of Agriculturein cooperation withARC-Grain Crops Institute

Printed and published by Department of Agricultureand obtainable from Resource Centre, Directorate Agricultural Information ServicesPrivate Bag X144, Pretoria, 0001 South Africa

ContributionsM.J. du PlessisD. FourieA.J. LiebenbergM.M. LiebenbergC.J. van Zyl

This publication is available on the web: www.nda.agric.za/publications

Information provided by

ARC-Grain Crops Institute (ARC-GCI)Private Bag X1251, Potchefstroom, 2520Tel. (018) 299 6100

Dry beans is at present regarded as one ofthe most important field crops in South Africaon account of its high protein content anddietary benefits.

Of all the annual leguminous food cropsthat are harvested for dry seeds, theordinary bean is by far the most important.Dry beans (Phaseolus spp.) originated inCentral and South America. Within thegenus Phaseolus there are three specieswhich are agronomically important inSouth Africa.

Phaseolus vulgarisMany different types and colours, themost important of which are: smallwhite, red speckled or sugar beans,carioca and green beans

Phaseolus acutifoliusTepary beans

Phaseolus coccineusLarge white kidney beans

Within each species there are many seedtypes which differ in size, shape andcolour. Within each type there aredifferent cultivars and the seeds ofthese cultivars differ very little fromone another. However, considerabledifferences may occur in adaptability,growth habit, disease resistance andmany other characteristics. In thispublication, only P. vulgaris is discussed,except where mentioned otherwise.

1

CLIMATIC REQUIREMENTSThe dry bean is an annual crop which thrivesin a warm climate. It grows optimally attemperatures of 18 to 24 °C. The maximumtemperature during flowering should notexceed 30 °C for P. vulgaris and 26 °C forP. coccineus. High temperatures duringthe flowering stage lead to abscission offlowers and a low pod set, resulting inyield loss. Day temperatures below 20 °Cwill delay maturity and cause empty maturepods to develop. Cultivated under rainfedconditions the crop requires a minimumof 400 to 500 mm of rain during thegrowing season, but an annual total of600 to 650 mm is considered ideal.

SOIL REQUIREMENTSBeans have to be planted in warm soils(minimum temperatures preferably above13 °C) after all danger of frost has passed.They grow well in soils with a depth of atleast 90 cm, that have no deficiencies,and are well drained. Sandy loam, sandyclay loam or clay loam with a clay contentof between 15 and 35 % is suitable. Withsandy soils, problems of low fertility ornematode damage may occur.Beans prefer an optimum soil pH (H2O) of5,8 to 6,5, and are very sensitive to acidic(pH (H2O) < 5,2) soils (acid saturationabove 10 %). They will also not grow wellin soils that are compacted, too alkalineor poorly drained.

2

CULTIVAR CHOICEThe National Dry Bean Cultivar Trials areconducted by the ARC–GCI annually andthe information is published by the DPOin SA Dry Beans. Dry beans are classifiedinto types according to:

Colour and seed sizeSmall white beans (15–25 g/100 seeds),used mainly for canning purposes; 10 to20 % of local production

Red speckled or speckled sugar beans(red speckles on a beige background)(40–55 g/100 seeds); 65 to 75 % oflocal production

Large white kidney beans (80–100 g/100 seeds); 5 to 10 % of localproduction

Carioca beans (khaki stripes on a beigebackground) 20 to 25 g/100 seeds);3 to 5 % of local production

Alubia beans (large white) (45–55 g/100 seeds); 1 to 5 % of localproduction

Growth habittype 1: determinate or bush type

type 2: indeterminate compact upright

type 3: indeterminate runner type(short runners)

3

Growing seasonTemperatures, especially during the night,determine the length of the growingseason of a cultivar:

short (85–94 days)

medium (95–104 days)

long (105–115 days).

A cultivar can have any combination ofthese characteristics. Further informationon cultivars can be obtained from theARC-GCI. Seed is produced by Dry BeanSeed (Pty Ltd) tel. (012) 325 1850 andPANNAR tel. (033) 413 1131.

SEED QUALITYFor successful production, it is importantthat high-quality (certified) seed with ahigh germination percentage (80 % orhigher) be used. This production costfactor is slight when compared toprobable yield losses due to disease orpoor stand. Low-quality seed can causea poor and an uneven stand, resulting inuneven maturity, harvesting problems andyield losses. Using disease-free seed willreduce the incidence of seed-bornediseases such as bean common mosaicvirus (BCMV), bacterial diseases (commonblight, halo blight and bacterial brownspot) and the fungal disease, anthrac-

4

5

nose. Other benefits of disease-freeseed are that it is:

labelled to indicate germinationpercentageguaranteed true to type and ensureshomogeneityguaranteed free of weed seeds andforeign matter.

SOIL PREPARATIONSeedbed preparation for the planting ofdry beans follows the same pattern asthat for any row crop planted in thespring. The seedbed must be deep, leveland firm because this ensures bettersurface contact between the seed andthe soil, increasing the absorption ofmoisture. A level seedbed also facilitatesplanting to a uniform depth.

FERTILISATIONIt is recommended that beans be plantedon soils which have been previously wellfertilised. General fertility is moreadvantageous than direct fertilisation,because beans are sensitive to high con-centrations of mineral salts.

MacronutrientsThe total withdrawal figure per 1 ton ofdry bean seed produced is about 36 kg N,8 kg P and 18 kg K.

Nitrogen (N)Inoculation of dry bean seed is regardedas ineffective. Consequently, dry beansshould be considered as incapable ofsatisfying all of their nitrogen requirementsthrough N-fixation. The application of allthe nitrogen at planting time is recom-mended, particularly where undecomposedmaterial has been ploughed in beforeplanting.

Deficiency symptomsLower leaves become light green and thenyellow and eventually die. Young leavesmay be lighter green than normal.

Guidelines for nitrogen application

Yield potential (t/ha) 1,5 2,0 2,5

N fertilisation (kg/ha) 15,0 30,0 45,0

Phosphorus (P)Under commercial production the yieldresponses to phosphorus fertilisationare not dramatic in dry beans and P isnot normally a yield-restrictive factor.Under subsistence production, wheresmall quantities of fertiliser are appliedP can be a yield-limiting factor. Wherethe P content of the soil is lower than20 ppm (Bray 1) it is recommended thatsuperphosphate be broadcasted and

6

ploughed into the soil to a depth of15 to 20 cm before planting.

Phosphorus fertiliser must still be band-placed at the time of planting. In low pHsoils, phosphorus can be utilisedefficiently by bandplacing 3,5 cm tothe side and 5 cm below the seed.

Deficiency symptomsYoung leaves are small and dark green, olderleaves senesce prematurely. Plants haveshort internodes and reduced branching.

Guidelines for phosphorus fertilisation

Soil analysis P application forpotential (t/ha)

Ambic Bray 1 1,5 2,0 2,5

P (mg/kg) P fertilisation(kg/ha)

10 13 16 22 28 15 20 12 16 20 20 27 10 13 16 25 34 9 12 15>45 >55 5 5 5

Potassium (K)When dry beans are grown on soils witha high clay content, potassium is notnormally a limiting factor. Deficiencies aremost likely to occur on sandy soils with ananalysis of less than 50 ppm K. The opti-mum leaf content is 2 % potassium.

7

Deficiency symptomsBright yellow chlorosis of older leaves,appearing from the margins and then ex-tending rapidly to the centre of leaflets.

Guidelines for potassium fertilisation

Soil analysis K fertilisation forpotential (t/ha)

Ambic 1 NH4OAc 1,5 2,0 2,5

K (mg/kg) K fertilisation(kg/ha)

40 40 22 27 3260 59 19 24 2980 78 17 21 26

100 98 15 19 24>100 >98 0 0 0

Micronutrients

Molybdenum (Mo)If the soil has a pH (H2O) of less than 6,a seed treatment of 100 g sodium molyb-date per 50 kg seed and/or a foliar sprayof 100 g sodium molybdate per hectareshould be given. If the pH (H2O) is below5,3 and there are no Rhizobia in the soil,no results will be achieved by applyingmolybdenum.

Deficiency symptoms are similar to thoseof nitrogen because it is important for Nmetabolism.

8

Zinc (Zn)The critical level of zinc in bean tissue is15 to 20 ppm. Levels higher than 120 ppmcan decrease yields. The availability ofzinc is highest in slightly acid soils(pH 6,0–6,8) and lowest at pH(H2O)above 7,4.

Deficiency symptomsPale, yellow leaves, especially betweenveins and near the tips. The plants be-come deformed and dwarfed and may die.Pod formation is hampered and the plantsare slow to mature.

Manganese (Mn)Deficiencies only occur on soils with ahigh pH value. Symptoms include smallleaves with a mosaic yellowing in theinterveinal areas while the veins remainprominently green. Deficiencies can becorrected by applying manganese sulphate(MnSO4) at 15 to 20 kg/ha.

Boron (B)Boron toxicity is a more frequent problemthan deficiency and symptoms includechlorosis and dwarfing. With time, thechlorosis increases and resembles burn,with the leaf margins curling in. Beansshould not follow a sunflower crop whichhas received boron fertiliser.

9

Iron (Fe)Deficiency occurs on calcareous or salinesoils where pH (H2O) values are above7,4. Symptoms are characterised bybright yellow leaves and green veins.Deficiencies can be rectified by a 1 %FeSO4 solution or chelate applied as afoliar spray.

SOIL ACIDITY (pH)The optimum soil pH levels for dry beansare:

pH (H2O): 5,8–6,5

pH (KCl): 4,8–5,5.

The percentage of acid saturation has tobe lower than 10 % for the cultivation ofdry beans. The soluble aluminium contenthas to be less than 25 to 30 %.

The pH can be raised (acid saturationreduced) by applications of agriculturallime. These applications to acid (low pH)soils can make certain micronutrients,such as molybdenum, more available tothe plant. The availability of phosphorusis influenced by the pH. It is readilyavailable at a pH (H2O) of 6 to 7.

Calcium and magnesium deficiencies canbe alleviated with agricultural lime. HighpH soils are often associated with anexcess of sodium salts which reducenutrient uptake. Beans will tolerate a

10

sodium saturation percentage of up to8 or 10 and an electrical conductivity ofup to 1 mmho/cm.

PLANTING DATEThe most suitable planting date is deter-mined by the following factors:

Correct soil temperatureProbability of heavy rain which may leadto soil crusting and restrict seedlingemergencePossibility of high temperatures later inthe season which may cause blossom dropLength of the growing season (hightemperatures during flowering, rainduring harvest and frost damageshould be avoided)Crop rotation programmes (position of thebean crop in the total crop setup, i.e.planted after another crop, such as maize).

Planting dates are mainly restricted bythe possible occurrence of frost (plantingtoo late), and rain at harvesting, resultingin poor quality (planting too early). Plant-ing dates in South Africa range fromNovember to mid-January in areas wherefrost occurs. In frost-free areas, Marchand April are the best months for plant-ing beans. The large white kidney bean(P. coccineus) is an exception and is plantedfrom mid-November to mid-Decemberand is not adapted to winter production.

11

SPACING, PLANT POPULATIONAND PLANTING DEPTH

The between-row spacing for all types ofbeans under commercial production is900 mm because dry beans are usuallycultivated in rotation with maize. Forearly maturing cultivars, especially thosewith a determinate growth habit, a rowspacing of 750 mm is recommended ifmechanisation is practical (see table).

Spacing and plant population

Type Spacing Spacing Plantwithin rows between rows population

(mm) (mm) seeds/haEarly maturing,determinate 75 750 177 000

Medium and latematuring 75 900 150 000

Large whitekidney 100–150 900 115 000

Planting depth is determined by the soiltexture and its moisture content. Generallythe seeds are placed 2,5 to 5,0 cm belowthe soil surface.

IRRIGATIONIrrigation offers the potential forincreasing yields and enabling productionin otherwise unsuitable soils. Sprinkler

12

irrigation is the most frequent means ofirrigation for dry beans. The system usedis determined by the size and shape ofthe lands, as well as available labour andcapital. In areas where water is unre-stricted (not merely supplementary irri-gation), the soil should be wet to fieldcapacity to the depth of the 1 m rootzone before planting. As soon as the soilis sufficiently dry, the seedbed should beprepared and planted and thereafter thefield should not be irrigated until theseedlings have emerged.

Irrigation scheduling is essential foroptimum yield per unit of water. Thecritical, moisture-sensitive growth stagesare flowering and early pod set whichoccur at 40 to 50 % and 50 to 60 % ofthe growing season. It is important thatirrigation cycles be correctly scheduled,because excess moisture can createconditions conducive to root rot andSclerotinia. Moisture stress can alsoaggravate some root rots such asFusarium oxysporum. Irrigation shouldcease when a quarter of the bean podshave turned yellow. For the correctirrigation scheduling, expert advice mustbe obtained.

HARVESTINGDry beans have a moisture content ofabout 50 % at physiological maturity.

13

The beans, however, are only ready forharvesting when the moisture contentdrops to 16 %, the ideal being 15 %.Seeds may split during threshing whenthe moisture content is less than 12 %and such seeds are rejected by cannersand seed companies. It is difficult toclean without further seed split orbroken seed coats. Dry beans should beharvested when all the pods have turnedyellow, but before they have become sodry that the pods begin to shatter.

Dry beans can be harvestedas follows:

Handpulling and threshing by drivinga tractor over them on a threshingfloor. Smaller volumes can bethreshed by hand by beating with astick covered in a hessian sack. Thewind can be used to separate the seedfrom the chaff

Partially mechanised systems, wherethe plants are pulled up by hand,placed in windrows and threshed witha harvester or stacked, whereafterthey are threshed with a stationarythreshing machine

Fully automated system with mechanicalpulling. The beans are raked into wind-rows and threshed by means of anautomated combine.

14

TipsPulling of beans should start when the moisturecontent of the pods is temporarily high (toprevent shattering), i.e. early in the morningbefore the dew has evaporated.Mechanised harvesting must be done whenthere is no danger of crop damage by rain.To prevent cracking and splitting beans should bethreshed at slow cylinder speeds with a machineequipped with an axial flow threshing mechanism.

WEED CONTROLEffective weed control is a prerequisitefor high dry-bean yields. Dry beans, beinglow-growing plants, struggle to competewith or overshadow weeds. Early controlis extremely important, because the rootsystem of the plant develops at thisstage and some weeds secrete chemicalinhibitors which limit plant growth. At alater stage weeds hamper the harvestingand threshing processes, adverselyaffecting the quality of the crop.

Mechanical weed controlMechanical weed control should beginduring seedbed preparation (remove allweeds) and be repeated with a tillerbetween the rows when necessary up tothe flowering stage. Care should be takenthat implements do not damage the crop

15

by using row spacings which permit easyaccess and taking care that roots are notdamaged. Cultivation between the rows isalso advantageous because it loosens thesoil and improves aeration and waterpenetration. Weeds in the row haveto be handpulled.

Chemical weed controlChemical weed control can be implementedbefore planting or before and/or afteremergence. A sufficient number ofherbicides have been registered tocontrol all weeds throughout the entiregrowing period of dry beans. Informationin this regard is obtainable from thedifferent agrochemical companies.

DISEASES AND PESTSDiseases and pests may have been partiallyresponsible for the unstable productionthat has been experienced in the past.Incidence and severity vary betweenseasons because of environmental andmanagement practices. Integrated diseaseand pest management, using all suitablecontrol measures, is recommended.

16

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17

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poru

mf.

sp.

pha

seol

i

Pseu

dom

onas

sava

stan

oi p

vph

aseo

licol

a

Visi

ble

in f

ield

as

grou

ps o

fye

llowi

ng p

lant

s. L

eave

s be

com

eye

llow

and

die

off.

Int

erna

ldi

scol

orat

ion

of lo

wer

stem

(vas

cula

r ti

ssue

). Yo

unge

r pl

ants

stun

ted,

may

wilt

and

die

Leaf

sym

ptom

s in

itia

lly a

ppea

r as

smal

l, wa

ter-

soak

ed le

sion

s on

the

unde

rsid

e. L

esio

ns t

urn

redd

ish

brow

n an

d be

com

e ne

crot

ic w

ith

age.

The

mos

t ch

arac

teri

stic

sym

ptom

is a

ligh

t-gr

een

zone

(hal

o) s

urro

undi

ng t

he n

ecro

tic

spot

. Pod

sym

ptom

s ar

e gr

easy

,wa

ter-

soak

ed s

pots

of

vari

ous

size

s. L

esio

n m

argi

ns m

ay t

urn

brow

n as

the

y m

atur

e. L

esio

nsno

rmal

ly s

tay

gree

n on

dry

pod

s.Pl

ants

wit

h in

fect

ed v

ascu

lar

syst

ems

(sys

tem

ic in

fect

ion)

appe

ar s

tunt

ed, g

ener

ally

sho

wing

a lim

e-gr

een

colo

ur a

nd a

red

dish

disc

olor

atio

n at

the

nod

es

Hot

and

dry

,st

ress

con

di-

tion

s

Cool

and

hum

id

Crop

rot

atio

n wi

th g

rain

crop

s (m

aize

, whe

at, e

tc);

deep

plo

ughi

ng; a

void

str

ess

and

dam

age

to s

tem

s (b

y fo

rex

ampl

e be

an f

ly, h

oein

g,m

achi

nery

)

Plan

t di

seas

e-fr

ee s

eed;

wor

kbe

an d

ebri

s in

to t

he s

oil

afte

r ha

rves

ting

; app

lyco

pper

-bas

ed b

acte

rici

des

asa

prev

enti

ve m

easu

re; c

ontr

olwe

eds

and

volu

ntee

r be

ans

Caus

al o

rgan

ism, sy

mpt

oms,

idea

l con

dition

s, p

reve

ntion

and

trea

tmen

t of

impo

rtan

t dr

y-be

an d

isea

ses

( con

tinue

d)

Disea

seCa

usal

Sym

ptom

sId

eal

Prev

ention

/tre

atmen

tor

ganism

cond

itions

20

Caus

al o

rgan

ism, sy

mpt

oms,

idea

l con

dition

s, p

reve

ntion

and

trea

tmen

t of

impo

rtan

t dr

y-be

an d

isea

ses

(con

tinue

d)

Disea

seCa

usal

Sym

ptom

sId

eal

Prev

ention

/tre

atmen

tor

ganism

cond

itions

Powd

ery

mild

ew

*Pyt

hium

*Rhi

zoct

o-ni

a ro

ot r

ot

Erys

iphe

poly

goni

Pyth

ium

spp

Rhiz

octo

nia

sola

ni

Ori

gina

lly f

aint

bla

cken

ed s

uper

fi-

cial

sta

rlik

e bl

otch

es, b

ecom

ing

whit

e, c

oale

scin

g to

cov

er a

eria

lpa

rts

in a

dry

pow

dery

film

.Pl

ants

may

dry

out

and

bec

ome

defo

liate

d

Poor

em

erge

nce,

wilt

ing

and

dyin

gof

f of

you

ng s

eedl

ings

. Wat

er-

soak

ed, t

hen

grey

to

brow

n le

sion

sne

ar s

oil s

urfa

ce,

spre

adin

g to

ste

ms

and

root

s an

dle

adin

g to

sof

t ro

t. A

reas

in r

ows

with

dea

d pl

ants

bor

dere

d by

stun

ted

plan

ts. I

n se

vere

cas

es,

larg

e ar

eas

may

be

affe

cted

Redd

ish-

brow

n le

sion

s on

lowe

rst

ems,

bec

omin

g su

nken

and

spre

adin

g to

caus

e wi

ltin

g an

ddy

ing

off

of p

lant

. Oft

en m

ore

seve

re a

t se

edlin

g st

age

but

may

caus

e st

unti

ng a

nd u

neve

n m

atur

a-ti

on in

old

er p

lant

s

Hot

and

mod

erat

ely

hum

id

Cool

and

wet

cond

itio

ns

Mod

erat

e to

high

soi

lm

oist

ure

and

tem

pera

ture

s

Resi

stan

t cu

ltiv

ars,

sui

tabl

efu

ngic

ides

Seed

tre

atm

ent

with

sui

tabl

efu

ngic

ides

; goo

d dr

aina

ge;

crop

rot

atio

n

Seed

tre

atm

ent

with

sui

tabl

efu

ngic

ides

; goo

d dr

aina

ge;

deep

plo

ughi

ng; s

hallo

wpl

anti

ng; c

rop

rota

tion

21

Caus

al o

rgan

ism, sy

mpt

oms,

idea

l con

dition

s, p

reve

ntion

and

trea

tmen

t of

impo

rtan

t dr

y-be

an d

isea

ses

(con

tinue

d)

Disea

seCa

usal

Sym

ptom

sId

eal

Prev

ention

/tre

atmen

tor

ganism

cond

itions

Rust

Scab

Scle

roti

nia

(whi

tem

ould

)

Uro

myc

esap

pend

icul

atus

Elsi

noë

phas

eoli

Scle

roti

nia

scle

roti

orum

Smal

l, wh

ite

spot

s de

velo

p on

leav

es,

(som

etim

es o

nly

on u

nder

side

),le

sion

s en

larg

e an

d bu

rst

open

to

form

rai

sed,

rus

t-co

lour

ed p

ustu

les

rele

asin

g a

redd

ish-

brow

n du

st(s

pore

s) w

hen

rubb

ed. S

pore

s m

aybe

com

e bl

ack

at e

nd o

f se

ason

.Pu

stul

es s

omet

imes

sur

roun

ded

byye

llow

halo

or

necr

otic

(dea

d) t

issu

e.Le

aves

may

yel

low

and

die

off.

Pust

ules

on

pods

elo

ngat

ed.

New

leav

es a

nd s

hoot

s cu

rl u

p-wa

rds.

On

olde

r le

aves

, gre

y to

light

-bro

wn c

ircu

lar

scab

-lik

ele

sion

s, u

sual

ly c

once

ntra

ted

near

the

vein

s. S

imila

r le

sion

s, d

arke

ning

with

age

, on

the

pods

Earl

y sy

mpt

oms

smal

l, wa

ter-

soak

edsp

ots

on le

aves

and

ste

m, f

ollo

wed

by w

hite

mas

ses

of m

ycel

ium

.S

cler

otia

for

m o

n th

is m

ass

and

turn

bla

ck a

fter

7–1

0 da

ys. D

ried

out

infe

cted

tis

sue

have

a c

hara

c-te

rist

ic b

leac

hed

appe

aran

ce

Mod

erat

ete

mpe

ratu

res,

alte

rnat

e we

tan

d dr

y pe

riod

s,wi

ndy

Hot

and

hum

id

Hum

id, d

ense

leaf

can

opy

Resi

stan

t cu

ltiv

ars;

sui

tabl

efu

ngic

ides

; wor

k in

pla

ntde

bris

aft

er h

arve

stin

g; r

e-m

ove

volu

ntee

r be

ans

Plan

t di

seas

e-fr

ee s

eed;

plan

t re

sist

ant

cult

ivar

s;ap

ply

suit

able

fun

gici

des

Crop

rot

atio

n wi

th m

aize

; use

dise

ase-

free

see

d; s

ched

ule

irri

gati

on c

ycle

s so

tha

tpl

ants

do

not

rem

ain

wet

for

long

per

iods

; avo

id o

ver-

irri

gati

on; a

pply

sui

tabl

efu

ngic

ides

22

Caus

al o

rgan

ism, sy

mpt

oms,

idea

l con

dition

s, p

reve

ntion

and

trea

tmen

t of

impo

rtan

t dr

y-be

an d

isea

ses

(con

tinue

d)

Disea

seCa

usal

Sym

ptom

sId

eal

Prev

ention

/tre

atmen

tor

ganism

cond

itions

*Scl

erot

ium

root

rot

(sou

ther

nbl

ight

)

Scle

roti

umro

lfsi

iGr

ey w

ater

-soa

ked

lesi

ons,

bec

omin

gbr

own,

nea

r th

e so

il su

rfac

e,sp

read

ing

to t

he t

apro

ot a

ndle

adin

g to

wilt

ing

and

deat

h of

the

plan

t. L

ower

leav

es m

ay a

lso

beaf

fect

ed. C

hara

cter

isti

c sm

all

roun

d lig

ht-y

ello

w to

bro

wnsc

lero

tia

and

whit

e fu

ngus

gro

wth

visi

ble

on e

stab

lishe

d le

sion

s.

Dry

wea

ther

follo

wed

by h

otan

d hu

mid

Good

dra

inag

e; c

rop

rota

tion

;wo

rk in

bea

n st

ubbl

e af

ter

harv

esti

ng; d

eep

plou

ghin

g

*Dis

ease

s of

the

roo

ts a

nd s

tem

, kno

wn a

s “r

oot

rot”

, oft

en o

ccur

in a

com

plex

and

can

incl

ude

any

of t

he f

ollo

wing

:fu

sari

um, p

ythi

um, r

hizo

cton

ia, c

harc

oal r

ot a

nd s

cler

otiu

m r

oot

rot

(Sou

ther

n bl

ight

), th

e fi

rst

thre

e be

ing

the

mos

tfr

eque

nt. T

he la

tter

fou

r ca

n al

so c

ause

rot

ting

of

seed

and

dam

ping

off

. To

som

e ex

tent

roo

t ro

t ca

n be

pre

vent

ed,

but

not

trea

ted.

Fun

gici

des

can

only

be

appl

ied

to s

eed

as a

pre

vent

ive

mea

sure

aga

inst

Pyt

hium

and

Rhi

zoct

onia

roo

tro

t

23

Pest

s

Inse

ctScien

tific

name

Dam

age

Tre

atmen

t

Blac

k be

an a

phid

Aph

is f

abae

Vect

ors

of v

ario

us v

irus

esA

pply

sui

tabl

e in

sect

icid

e

Grou

ndnu

t ap

hid

Aph

is c

racc

ivor

aVe

ctor

s of

var

ious

vir

uses

App

ly s

uita

ble

inse

ctic

ide

Toba

cco

whit

efly

Bem

isia

tab

aci

Pote

ntia

l vec

tor

of b

ean

No

inse

ctic

ide

curr

entl

ygo

lden

mos

aic

viru

sre

gist

ered

Toba

cco

leaf

hopp

erJa

cobi

ella

fas

cial

isSu

ck s

ap f

rom

leav

esN

o tr

eatm

ent

nece

ssar

y

Bean

see

d m

aggo

tD

elia

pla

tura

Mag

gots

att

ack

coty

ledo

ns,

Cont

rol w

ith

a se

ed d

ress

ing

min

e in

to s

tem

s be

low

soil

inse

ctic

ide

leve

l and

pup

ate

Bean

ste

m m

aggo

tO

phio

myi

a sp

ence

rella

Mag

gots

min

e in

to s

tem

sN

o in

sect

icid

e cu

rren

tly

Oph

iom

yia

phas

eoli

and

pupa

tere

gist

ered

Spot

ted

mai

ze b

eetl

eA

styl

us a

trom

acul

atus

Feed

on

polle

n, d

estr

oyN

o in

sect

icid

e cu

rren

tly

flow

ers

regi

ster

ed

CMR

beet

leM

ylab

ris

ocul

ata

Des

troy

flo

wers

App

ly s

uita

ble

inse

ctic

ide

24

Pest

s (c

ontinu

ed)

Inse

ctScien

tific

name

Dam

age

Tre

atmen

t

Blac

k m

aize

bee

tle

Het

eron

ycus

ara

tor

Dam

age

stem

s on

or

bene

ath

App

ly s

uita

ble

inse

ctic

ide

soil

surf

ace

Chaf

er b

eetl

eA

dore

tus

crib

rosu

sFe

ed o

n yo

ung

leav

es, p

etal

sA

pply

sui

tabl

e in

sect

icid

eA

dore

tus

tess

ulat

usan

d po

llen

Bean

bug

Clav

igra

llaSu

ck s

ap f

rom

leav

es, s

tem

sN

o in

sect

icid

e cu

rren

tly

tom

ento

sico

llis

and

pods

—ca

use

wilt

ing

ofre

gist

ered

deve

lopi

ng p

ods

Tip

wilt

erA

nopl

ocne

mis

Suck

sap

fro

m s

tem

s—ca

use

No

inse

ctic

ide

curr

entl

ycu

rvip

eswi

ltin

g an

d dy

ing

of t

ips

ofre

gist

ered

shoo

ts

Gree

n ve

geta

ble

bug

Nez

ara

viri

dula

Suck

sap

fro

m p

ods—

caus

eN

o in

sect

icid

e cu

rren

tly

brow

ing

of s

eeds

insi

dere

gist

ered

Com

mon

cut

worm

Agr

otis

seg

etum

Dam

age

stem

s on

or

bene

ath

App

ly s

uita

ble

inse

ctic

ide

soil

surf

ace

Afr

ican

bol

lwur

mH

elic

over

pa a

rmig

era

Feed

into

pod

s an

d da

mag

eA

pply

sui

tabl

e in

sect

icid

ese

eds

Cabb

age

sem

i-Tr

icho

plus

iaFe

ed in

to p

ods

and

dam

age

App

ly s

uita

ble

inse

ctic

ide

loop

eror

icha

lcea

seed

s

25

Pest

s (c

ontinu

ed)

Inse

ctScien

tific

name

Dam

age

Tre

atmen

t

Am

eric

anLi

riom

yza

trif

olii

Larv

ae t

unne

l int

o le

aves

App

ly s

uita

ble

inse

ctic

ide

leaf

min

er

Sout

h A

mer

ican

Liri

omyz

aLa

rvae

tun

nel i

nto

leav

esN

o in

sect

icid

e cu

rren

tly

leaf

min

er/P

otat

ohu

idob

rens

isre

gist

ered

leaf

min

er

Bean

flo

wer

thri

psM

egal

urot

hrip

sFe

ed in

flo

wers

, cau

sing

App

ly s

uita

ble

inse

ctic

ide

sjös

tedt

ia

roug

hene

d, s

ilver

y te

xtur

eon

pod

s

Bean

thr

ips

Seri

coth

rips

Feed

in f

lowe

rs, c

ausi

ngA

pply

sui

tabl

e in

sect

icid

eoc

cipi

talis

a ro

ughe

ned,

silv

ery

text

ure

on p

ods

Bean

wee

vil

Aca

ntho

scel

ides

Larv

ae e

nter

see

d an

d ho

llow

App

ly s

uita

ble

inse

ctic

ide

obte

ctus

it o

ut b

y fe

edin

g

Bean

gal

l wee

vil

Alc

idod

esLa

rvae

ent

er s

tem

s, p

upat

eA

pply

sui

tabl

e in

sect

icid

eer

ythr

opte

rus

in t

he g

alls

for

med

26

EnquiriesFor futher information on bean productioncontact:

ARC-Grain Crops Institute (ARC–GCI)Private Bag X1251Potchefstroom2520Tel. (018) 299 6100Dry Bean Producers’ Organisation (DPO)P.O. Box 26269Arcadia0007Tel. (012) 325 1850and subscribe to SA Dry Beans,a quarterly magazine.

The Dry Bean Production Manual canalso be ordered from the same address.

27