Editor DR A.J. LIEBENBERG

Dry bean production

2009 2002 Second print 2001 First print

Compiled by Directorate Agricultural Information Services Department of Agriculture, Forestry and Fisheries

In cooperation with ARC-Grain Crops Institute

Printed and published by Department of Agriculture, Forestry and Fisheries

Obtainable from Resource Centre, Directorate Agricultural Information Services Private Bag X144, Pretoria, 0001 South Africa

Also available on the web at www.nda.agric.za/publications

Contributions

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

Information provided by

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

1

Dry beans is at present regarded as one of the most im portant field crops in South Africa on account of its high protein content and dietary benefits.

Of all the annual leguminous food crops that are harvested for dry seeds, the ordinary bean is by far the most important. Dry beans (Phaseolus spp.) originated in Central and South America. Within the genus Phaseolus there are three species which are agronomically important in South Africa.

z Phaseolus vulgaris

Many different types and colours, the most im-portant of which are: small white, red speckled or sugar beans, carioca and green beans

z Phaseolus acutifolius Tepary beans

z Phaseolus coccineus Large white kidney beans

Within each species there are many seed types which differ in size, shape and colour. Within each type there are different cultivars and the seeds of these cultivars differ very little from one another. However, considerable differences may occur in adaptability, growth habit, disease resistance and many other characteristics. In this publication, only P. vulgaris is discussed, except where mentioned otherwise.

Climatic requirements

The dry bean is an annual crop which thrives in a warm climate. It grows optimally at temperatures

2

of 18 to 24 °C. The maximum temperature during flowering should not exceed 30 °C for P. vulgaris and 26 °C for P. coccineus. High temperatures during the flowering stage lead to abscission of flowers and a low pod set, resulting in yield loss. Day temperatures below 20 °C will delay maturity and cause empty mature pods to develop. Cultivated under rainfed conditions the crop requires a minimum of 400 to 500 mm of rain during the growing season, but an annual total of 600 to 650 mm is considered ideal.

Soil requirementsBeans have to be planted in warm soils (minimum temperatures preferably above 13 °C) after all danger of frost has passed.

They grow well in soils with a depth of at least 90 cm, that have no deficiencies, and are well drained. Sandy loam, sandy clay loam or clay loam with a clay content of between 15 and 35 % is suitable. With sandy soils, problems of low fertility or nematode damage may occur.

Beans prefer an optimum soil pH (H2O) of 5,8 to 6,5, and are very sensitive to acidic (pH (H2O) < 5,2) soils (acid saturation above 10 %). They will also not grow well in soils that are compacted, too alkaline or poorly drained.

Cultivar choiceThe National Dry Bean Cultivar Trials are conducted by the ARC–GCI annually and the information is published by the DPO in SA Dry Beans. Dry beans are classified into types according to:

3

Colour and seed size

z Small white beans (15–25 g/100 seeds), used mainly for canning purposes; 10 to 20 % of local production.

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

z Large white kidney beans (80–100 g/100 seeds); 5 to 10 % of local production.

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

z Alubia beans (large white) (45–55 g/100 seeds); 1 to 5 % of local production.

Growth habit

z Type 1: determinate or bush type

z Type 2: indeterminate compact upright

z Type 3: indeterminate runner type (short runners).

Growing season

Temperatures, especially during the night, determine the length of the growing season of a cultivar: z Short (85–94 days) z Medium (95–104 days) z Long (105–115 days).

A cultivar can have any combination of these characteristics. Further information on cultivars can be obtained from the ARC-GCI.

4

Seed is produced by Dry Bean Seed (Pty Ltd), tel: 012 325 1850 and PANNAR tel: 033 413 1131.

Seed quality

For successful production, it is important that high-quality (certified) seed with a high germination percentage (80 % or higher) be used. This production cost factor is slight when compared to probable yield losses due to disease or poor stand. Low-quality seed can cause a poor and an uneven stand, resulting in uneven maturity, harvesting problems and yield losses. Using disease-free seed will reduce the incidence of seed-borne diseases such as bean common mosaic virus (BCMV), bacterial diseases (common blight, halo blight and bacterial brown spot) and the fungal disease, anthracnose. Other benefits of disease-free seed are that it is: z Labelled to indicate germination percentage. z Guaranteed true to type and ensures

homogeneity. z Guaranteed free of weed seeds and foreign

matter.

Soil preparation

Seedbed preparation for the planting of dry beans follows the same pattern as that for any row crop planted in the spring. The seedbed must be deep, level and firm because this ensures better surface contact between the seed and the soil, increasing the absorption of moisture. A level seedbed also facilitates planting to a uniform depth.

5

Fertilisation

It is recommended that beans be planted on soils which have been previously well fertilised. General fertility is more advantageous than direct fertilisation, because beans are sensitive to high concentrations of mineral salts.

Macronutrients

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

NitrogeN (N)

Inoculation of dry bean seed is regarded as ineffective. Consequently, dry beans should be considered as incapable of satisfying all of their nitrogen requirements through N-fixation. The application of all the nitrogen at planting time is recommended, particularly where undecomposed material has been ploughed in before planting.

Deficiency symptoms

Lower leaves become light green and then yellow and eventually die. Young leaves may 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

6

PhosPhorus (P)

Under commercial production the yield responses to phosphorus fertilisation are not dramatic in dry beans and P is not normally a yield-restrictive factor. Under subsistence production, where small quantities of fertiliser are applied P can be a yield-limiting factor. Where the P content of the soil is lower than 20 ppm (Bray 1) it is recommended that superphosphate be broadcasted and ploughed into the soil to a depth of 15 to 20 cm before planting.

Phosphorus fertiliser must still be band placed at the time of planting. In low pH soils, phosphorus can be utilised efficiently by bandplacing 3,5 cm to the side and 5 cm below the seed.

Deficiency symptoms

Young leaves are small and dark green, older leaves senesce prematurely. Plants have short internodes and reduced branching.

Guidelines for phosphorus fertilisation

Soil analysis P application for potential (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

7

Potassium (K)

When dry beans are grown on soils with a high clay content, potassium is not normally a limiting factor. Deficiencies are most likely to occur on sandy soils with an analysis of less than 50 ppm K. The optimum leaf content is 2 % potassium.

Deficiency symptoms

Bright yellow chlorosis of older leaves, appearing from the margins and then extending rapidly to the centre of leaflets.

Guidelines for potassium fertilisation

Soil analysis K fertilisation for potential (t/ha)

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

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

40 40 22 27 32

60 59 19 24 29

80 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 molybdate per 50 kg seed and/or a foliar spray of 100 g sodium molybdate per hectare should be given. If the pH

8

(H2O) is below 5,3 and there are no Rhizobia in the soil, no results will be achieved by applying molybdenum.

Deficiency symptoms are similar to those of nitrogen because it is important for N metabolism.

ZiNc (ZN)

The critical level of zinc in bean tissue is 15 to 20 ppm. Levels higher than 120 ppm can decrease yields. The availability of zinc is highest in slightly acid soils (pH 6,0–6,8) and lowest at pH(H2O) above 7,4.

Deficiency symptoms

Pale, yellow leaves, especially between veins and near the tips. The plants become deformed and dwarfed and may die. Pod formation is hampered and the plants are slow to mature.

maNgaNese (mN)

Deficiencies only occur on soils with a high pH value. Symptoms include small leaves with a mosaic yellowing in the interveinal areas while the veins remain prominently green. Deficiencies can be corrected by applying manganese sulphate (MnSO4) at 15 to 20 kg/ha.

boroN (b)

Boron toxicity is a more frequent problem than deficiency and symptoms include chlorosis and dwarfing. With time, the chlorosis increases and resembles burn, with the leaf margins curling in.

9

Beans should not follow a sunflower crop which has received boron fertiliser.

iroN (Fe)

Deficiency occurs on calcareous or saline soils where pH (H2O) values are above 7,4. Symptoms are characterised by bright yellow leaves and green veins. Deficiencies can be rectified by a 1 % FeSO4 solution or chelate applied as a foliar spray.

Soil acidity (pH)

The optimum soil pH levels for dry beans are: z pH (H2O): 5,8–6,5 z pH (KCl): 4,8–5,5.

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

The pH can be raised (acid saturation reduced) by applications of agricultural lime. These applications to acid (low pH) soils can make certain micronutrients, such as molybdenum, more available to the plant. The availability of phosphorus is influenced by the pH. It is readily available at a pH (H2O) of 6 to 7.

Calcium and magnesium deficiencies can be alleviated with agricultural lime. High pH soils are often associated with an excess of sodium salts which reduce nutrient uptake. Beans will tolerate a sodium saturation percentage of up to 8 or 10 and an electrical conductivity of up to 1 mmho/cm.

10

Planting date

The most suitable planting date is determined by the following factors: z Correct soil temperature z Probability of heavy rain which may lead to soil

crusting and restrict seedling emergence z Possibility of high temperatures later in the

season which may cause blossom drop z Length of the growing season (high

temperatures during flowering, rain during harvest and frost damage should be avoided)

z Crop rotation programmes (position of the bean crop in the total crop setup, i.e. planted after another crop, such as maize).

Planting dates are mainly restricted by the possible occurrence of frost (planting too late), and rain at harvesting, resulting in poor quality (planting too early). Planting dates in South Africa range from November to mid-January in areas where frost occurs. In frost-free areas, March and April are the best months for planting beans. The large white kidney bean (P. coccineus) is an exception and is planted from mid-November to mid-December and is not adapted to winter production.

Spacing, plant population and planting depth

The between-row spacing for all types of beans under commercial production is 900 mm because dry beans are usually cultivated in rotation with maize. For early maturing cultivars, especially those with a determinate growth habit, a row spacing of 750 mm is recommended if mechanisation is practical (see table).

11

Spacing and plant population

Type Spacing within rows (mm)

Spacing between rows (mm)

Plant population seeds/ha

Early maturing, determinate

75 750 177 000

Medium and late maturing

75 900 150 000

Large white kidney

100–150 900 115 000

Planting depth is determined by the soil texture and its moisture content. Generally the seeds are placed 2,5 to 5,0 cm below the soil surface.

Irrigation

Irrigation offers the potential for increasing yields and enabling production in otherwise unsuitable soils. Sprinkler irrigation is the most frequent means of irrigation for dry beans. The system used is determined by the size and shape of the lands, as well as available labour and capital. In areas where water is unrestricted (not merely supplementary irrigation), the soil should be wet to field capacity to the depth of the 1 m root zone before planting. As soon as the soil is sufficiently dry, the seedbed should be prepared and planted and thereafter the field should not be irrigated until the seedlings have emerged.

Irrigation scheduling is essential for optimum yield per unit of water. The critical, moisture-sensitive growth stages are flowering and early pod set which occur at 40 to 50 % and 50 to 60 % of the growing season. It is important that irrigation cycles be correctly scheduled, because

12

excess moisture can create conditions conducive to root rot and Sclerotinia. Moisture stress can also aggravate some root rots such as Fusarium oxysporum. Irrigation should cease when a quarter of the bean pods have turned yellow. For the correct irrigation scheduling, expert advice must be obtained.

Harvesting

Dry beans have a moisture content of about 50 % at physiological maturity. The beans, however, are only ready for harvesting when the moisture content drops to 16 %, the ideal being 15 %. Seeds may split during threshing when the moisture content is less than 12 % and such seeds are rejected by canners and seed companies. It is difficult to clean without further seed split or broken seed coats. Dry beans should be harvested when all the pods have turned yellow, but before they have become so dry that the pods begin to shatter.

Dry beans can be harvested as follows: z Handpulling and threshing by driving a tractor

over them on a threshing floor. Smaller volumes can be threshed by hand by beating with a stick covered in a hessian sack. The wind can be used to separate the seed from the chaff.

z Partially mechanised systems, where the plants are pulled up by hand, placed in windrows and threshed with a harvester or stacked, whereafter they are threshed with a stationary threshing machine.

z Fully automated system with mechanical pulling. The beans are raked into wind rows and threshed by means of an automated combine.

13

Tips z Pulling of beans should start when the

moisture content of the pods is temporarily high (to prevent shattering), i.e. early in the morning before the dew has evaporated.

z Mechanised harvesting must be done when there is no danger of crop damage by rain.

z To prevent cracking and splitting beans should be threshed at slow cylinder speeds with a machine equipped with an axial flow threshing mechanism.

Weed control

Effective weed control is a prerequisite for high dry-bean yields. Dry beans, being low-growing plants, struggle to compete with or overshadow weeds. Early control is extremely important, because the root system of the plant develops at this stage and some weeds secrete chemical inhibitors which limit plant growth. At a later stage weeds hamper the harvesting and threshing processes, adversely affecting the quality of the crop.

Mechanical weed control

Mechanical weed control should begin during seedbed preparation (remove all weeds) and be repeated with a tiller between the rows when necessary up to the flowering stage. Care should be taken that implements do not damage the crop by using row spacings which permit easy access and taking care that roots

14

are not damaged. Cultivation between the rows is also advantageous because it loosens the soil and improves aeration and water penetration. Weeds in the row have to be handpulled.

Chemical weed control

Chemical weed control can be implemented before planting or before and/or after emergence. A sufficient number of herbicides have been registered to control all weeds throughout the entire growing period of dry beans. Information in this regard is obtainable from the different agrochemical companies.

DISEASES AND PESTS

Diseases and pests may have been partially responsible for the unstable production that has been experienced in the past. Incidence and severity vary between seasons because of environmental and management practices. Integrated disease and pest management, using all suitable control measures, is recommended.

15

Cau

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with

out v

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16

Cau

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, sym

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, pre

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et c

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bea

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ps

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l wee

ds a

nd

volu

ntee

r bea

ns

17

Cau

sal o

rgan

ism

, sym

ptom

s, id

eal c

ondi

tions

, pre

vent

ion

and

trea

tmen

t of i

mpo

rtan

t dry

-bea

n di

seas

es (c

ont.)

Dis

ease

Cau

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rgan

ism

Sym

ptom

sId

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ondi

tions

Prev

entio

n/tr

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ent

*Fus

ariu

m

root

rot (

dry

root

rot)

Fusa

rium

sol

ani

f. sp

pha

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iE

long

ated

redd

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olor

atio

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the

tapr

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(roo

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ay ro

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plet

ely)

, Pla

nts

may

bec

ome

stun

ted,

sho

w

prem

atur

e de

folia

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and

even

ually

die

. Sec

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ry

root

s ne

ar th

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il su

rface

. Inf

ectio

n m

ost s

ever

e w

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root

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tem

is u

nder

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ss

Stre

ss c

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, es

peci

ally

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ught

. Pa

th og

en o

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mos

t soi

ls a

nd

may

be

spre

ad in

so

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s)

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p ro

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er g

rain

cro

p; d

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void

stre

ss, p

oor

nutri

tion

and

dam

age

to

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s (b

y fo

r exa

mpl

e be

an

fly, h

oein

g, m

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); us

e til

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inim

ises

soi

l co

mpa

ctio

n

Fusa

rium

ye

llow

s (F

. wilt

)

Fusa

rium

ox

yspo

rum

f.

sp. p

hase

oli

Visi

ble

in fi

eld

as g

roup

s of

yel

low

ing

plan

ts. L

eave

s be

com

e ye

llow

and

die

off.

Inte

rnal

dis

colo

ratio

n of

lo

wer

ste

m (v

ascu

lar t

issu

e). Y

oung

er p

lant

s st

unte

d,

may

wilt

and

die

Hot

and

dry

, st

ress

con

ditio

nsC

rop

rota

tion

with

gra

in c

rops

(m

aize

, whe

at, e

tc);

deep

pl

ough

ing;

avo

id s

tress

and

da

mag

e to

ste

ms

(by

for

exam

ple

bean

fly,

hoe

ing,

m

achi

nery

)

Hal

o bl

ight

Pse

udom

onas

sa

vast

anoi

pv

phas

eolic

ola

Leaf

sym

ptom

s in

itial

ly a

ppea

r as

smal

l, w

ater

-soa

ked

lesi

ons

on th

e un

ders

ide.

Les

ions

turn

redd

ish

brow

n an

d be

com

e ne

crot

ic w

ith a

ge. T

he m

ost c

hara

cter

istic

sy

mpt

om is

a li

ght-g

reen

zon

e (h

alo)

sur

roun

ding

the

necr

otic

spo

t. P

od s

ympt

oms

are

grea

sy, w

ater

-soa

ked

spot

s of

var

ious

siz

es. L

esio

n m

argi

ns m

ay tu

rn b

row

n as

they

mat

ure.

Les

ions

nor

mal

ly s

tay

gree

n on

dry

po

ds. P

lant

s w

ith in

fect

ed v

ascu

lar s

yste

ms

(sys

tem

ic

infe

ctio

n) a

ppea

r stu

nted

, gen

eral

ly s

how

ing

a lim

e-gr

een

colo

ur a

nd a

redd

ish

disc

olor

atio

n at

the

node

s

Coo

l and

hum

id

Pla

nt d

isea

se-fr

ee s

eed;

wor

k be

an d

ebris

into

the

soil

afte

r ha

rves

ting;

app

ly c

oppe

r-ba

sed

bact

eric

ides

as

a pr

even

tive

mea

sure

; con

trol w

eeds

and

vo

lunt

eer b

eans

18

Cau

sal o

rgan

ism

, sym

ptom

s, id

eal c

ondi

tions

, pre

vent

ion

and

trea

tmen

t of i

mpo

rtan

t dry

-bea

n di

seas

es (c

ont.)

Dis

ease

Cau

sal o

rgan

ism

Sym

ptom

sId

eal c

ondi

tions

Prev

entio

n/tr

eatm

ent

Pow

dery

m

ildew

Ery

siph

e po

lygo

niO

rigin

ally

fain

t bla

cken

ed s

uper

ficia

l sta

rlike

blo

tche

s,

beco

min

g w

hite

, coa

lesc

ing

to c

over

aer

ial p

arts

in a

dry

po

wde

ry fi

lm.

Pla

nts

may

dry

out

and

bec

ome

defo

liate

d

Hot

and

m

oder

atel

y hu

mid

Res

ista

nt c

ultiv

ars,

sui

tabl

e fu

ngic

ides

*Pyt

hium

Pyt

hium

spp

Poo

r em

erge

nce,

wilt

ing

and

dyin

g of

f of y

oung

se

edlin

gs. W

ater

-soa

ked,

then

gre

y to

bro

wn

lesi

ons

near

soi

l sur

face

, spr

eadi

ng to

ste

ms

and

root

s an

d le

adin

g to

sof

t rot

. Are

as in

row

s w

ith d

ead

plan

ts

bord

ered

by

stun

ted

plan

ts. I

n se

vere

cas

es, l

arge

are

as

may

be

affe

cted

Coo

l and

wet

co

nditi

ons

See

d tre

atm

ent w

ith s

uita

ble

fung

icid

es; g

ood

drai

nage

; cro

p ro

tatio

n

*Rhi

zoct

o-ni

a ro

ot ro

tR

hizo

cton

ia s

olan

iR

eddi

sh-b

row

n le

sion

s on

low

er s

tem

s, b

ecom

ing

sunk

en a

nd s

prea

ding

to c

ause

wilt

ing

and

dyin

g of

f of

pla

nt. O

ften

mor

e se

vere

at s

eedl

ing

stag

e bu

t may

ca

use

stun

ting

and

unev

en m

atur

atio

n in

old

er p

lant

s

Mod

erat

e to

hig

h so

il m

oist

ure

and

tem

pera

ture

s

See

d tre

atm

ent w

ith s

uita

ble

fung

icid

es; g

ood

drai

nage

; de

ep p

loug

hing

; sha

llow

pl

antin

g; c

rop

rota

tion

Rus

tU

rom

yces

ap

pend

icul

atus

Smal

l, w

hite

spo

ts d

evel

op o

n le

aves

, (so

met

imes

onl

y on

und

ersi

de),

lesi

ons

enla

rge

and

burs

t ope

n to

form

ra

ised

, rus

t-col

oure

d pu

stul

es re

leas

ing

a re

ddis

h-br

own

dust

(spo

res)

whe

n ru

bbed

. Spo

res

may

bec

ome

blac

k at

end

of s

easo

n. P

ustu

les

som

etim

es s

urro

unde

d by

ye

llow

hal

o or

nec

rotic

(dea

d) ti

ssue

. Lea

ves

may

yel

low

an

d di

e of

f. P

ustu

les

on p

ods

elon

gate

d

Mod

erat

e te

mpe

ratu

res,

al

tern

ate

wet

and

dr

y pe

riods

, win

dy

Res

ista

nt c

ultiv

ars;

sui

tabl

e fu

ngic

ides

; wor

k in

pla

nt d

ebris

af

ter h

arve

stin

g; re

-mov

e vo

lunt

eer b

eans

19

Cau

sal o

rgan

ism

, sym

ptom

s, id

eal c

ondi

tions

, pre

vent

ion

and

trea

tmen

t of i

mpo

rtan

t dry

-bea

n di

seas

es (c

ont.)

Dis

ease

Cau

sal o

rgan

ism

Sym

ptom

sId

eal c

ondi

tions

Prev

entio

n/tr

eatm

ent

Sca

bEl

sino

ë ph

aseo

liN

ew le

aves

and

sho

ots

curl

upw

ards

. On

olde

r lea

ves,

gr

ey to

ligh

t-bro

wn

circ

ular

sca

b-lik

e le

sion

s, u

sual

ly

conc

entra

ted

near

the

vein

s. S

imila

r les

ions

, dar

keni

ng

with

age

, on

the

pods

Hot

and

hum

idP

lant

dis

ease

-free

see

d;

plan

t res

ista

nt c

ultiv

ars;

app

ly

suita

ble

fung

icid

es

Scl

erot

inia

(w

hite

m

ould

)

Scl

erot

inia

sc

lero

tioru

mEa

rly s

ympt

oms

smal

l, w

ater

-soa

ked

spot

s on

leav

es a

nd

stem

, fol

low

ed b

y w

hite

mas

ses

of m

ycel

ium

. Scl

erot

ia

form

on

this

mas

s an

d tu

rn b

lack

afte

r 7–1

0 da

ys.

Drie

d ou

t inf

ecte

d tis

sue

have

a c

hara

cter

istic

ble

ache

d ap

pear

ance

Hum

id, d

ense

le

af c

anop

yC

rop

rota

tion

with

mai

ze; u

se

dise

ase-

free

seed

; sch

edul

e irr

igat

ion

cycl

es s

o th

at p

lant

s do

not

rem

ain

wet

for l

ong

perio

ds; a

void

ove

r irrig

atio

n;

appl

y su

itabl

e fu

ngic

ides

*Scl

erot

ium

ro

ot ro

t (s

outh

ern

blig

ht)

Scl

erot

ium

rolfs

iiG

rey

wat

er-s

oake

d le

sions

, bec

omin

g br

own,

nea

r th

e so

il su

rface

, spr

eadi

ng to

the

tapr

oot a

nd le

adin

g to

w

iltin

g an

d de

ath

of th

e pl

ant.

Low

er le

aves

may

als

o be

af

fect

ed. C

hara

cter

istic

sm

all r

ound

ligh

t-yel

low

to b

row

n sc

lero

tia a

nd w

hite

fung

us g

row

th

visi

ble

on e

stab

lishe

d le

sion

s

Dry

wea

ther

fo

llow

ed b

y ho

t an

d hu

mid

Goo

d dr

aina

ge; c

rop

rota

tion;

w

ork

in b

ean

stub

ble

afte

r ha

rves

ting;

dee

p pl

ough

ing

* D

isea

ses

of th

e ro

ots

and

stem

, kno

wn

as “r

oot r

ot”,

ofte

n oc

cur i

n a

com

plex

and

can

incl

ude

any

of th

e fo

llow

ing:

fusa

rium

, pyt

hium

, rhi

zoct

onia

, ch

arco

al ro

t and

scl

erot

ium

root

rot (

Sou

ther

n bl

ight

), th

e fir

st th

ree

bein

g th

e m

ost f

requ

ent.

The

latte

r fou

r can

als

o ca

use

rotti

ng o

f see

d an

d da

mpi

ng

off.

To s

ome

exte

nt ro

ot ro

t can

be

prev

ente

d, b

ut n

ot tr

eate

d. F

ungi

cide

s ca

n on

ly b

e ap

plie

d to

see

d as

a p

reve

ntiv

e m

easu

re a

gain

st P

ythi

um a

nd

Rhi

zoct

onia

root

rot

20

Pes

ts (c

ont.)

Inse

ctSc

ient

ific

nam

eD

amag

eTr

eatm

ent

Bla

ck b

ean

aphi

d

Gro

undn

ut a

phid

Aph

is fa

bae

Aph

is c

racc

ivor

a

Vect

ors

of v

ario

us v

iruse

s

Vect

ors

of v

ario

us v

iruse

s

App

ly s

uita

ble

inse

ctic

ide

App

ly s

uita

ble

inse

ctic

ide

Toba

cco

whi

tefly

Bem

isia

taba

ciP

oten

tial v

ecto

r of b

ean

gold

en

mos

aic

viru

sN

o in

sect

icid

e cu

rren

tly

regi

ster

ed

Toba

cco

leaf

hopp

erJa

cobi

ella

fasc

ialis

Suc

k sa

p fro

m le

aves

No

treat

men

t nec

essa

ry

Bea

n se

ed m

aggo

t

Bea

n st

em m

aggo

t

Del

ia p

latu

ra

Oph

iom

yia

spen

cere

llaO

phio

myi

a ph

aseo

li

Mag

gots

atta

ck c

otyl

edon

s, m

ine

into

ste

ms

belo

w s

oil l

evel

and

pup

ate

Mag

gots

min

e in

to s

tem

s an

d pu

pate

Cont

rol w

ith a

see

d dr

essin

g in

sect

icid

e

No

inse

ctic

ide

curr

ently

re

gist

ered

Spo

tted

mai

ze b

eetle

CM

R b

eetle

Ast

ylus

atro

mac

ulat

us

Myl

abris

ocu

lata

Feed

on

polle

n, d

estro

y flo

wer

s

Des

troy

flow

ers

No

inse

ctic

ide

curr

ently

re

gist

ered

App

ly s

uita

ble

inse

ctic

ide

Bla

ck m

aize

bee

tle

Cha

fer b

eetle

Het

eron

ycus

ara

tor

Ado

retu

s cr

ibro

sus

Ado

retu

s te

ssul

atus

Dam

age

stem

s on

or b

enea

th s

oil s

urfa

ce

Feed

on

youn

g le

aves

, pet

als

and

polle

n

App

ly s

uita

ble

inse

ctic

ide

App

ly s

uita

ble

inse

ctic

ide

Bea

n bu

gC

lavi

gral

la to

men

tosi

colli

sS

uck

sap

from

leav

es, s

tem

s an

d po

ds—

caus

e w

iltin

g of

dev

elop

ing

pods

No

inse

ctic

ide

curr

ently

re

gist

ered

21

Pes

ts (c

ont.)

Inse

ctSc

ient

ific

nam

eD

amag

eTr

eatm

ent

Tip

wilt

er

Gre

en v

eget

able

bug

Ano

ploc

nem

is c

urvi

pes

Nez

ara

virid

ula

Suc

k sa

p fro

m s

tem

s—ca

use

wilt

ing

and

dyin

g of

tips

of s

hoot

s

Suc

k sa

p fro

m p

ods—

caus

e br

owin

g of

se

eds

insi

de

No

inse

ctic

ide

curr

ently

re

gist

ered

No

inse

ctic

ide

curr

ently

re

gist

ered

Com

mon

cut

wor

mA

grot

is s

eget

umD

amag

e st

ems

on o

r ben

eath

soi

l sur

face

App

ly s

uita

ble

inse

ctic

ide

Afri

can

bollw

urm

Hel

icov

erpa

arm

iger

aFe

ed in

to p

ods

and

dam

age

seed

sA

pply

sui

tabl

e in

sect

icid

e

Cab

bage

sem

i-loo

per

Tric

hopl

usia

oric

halc

eaFe

ed in

to p

ods

and

dam

age

seed

sA

pply

sui

tabl

e in

sect

icid

e

Am

eric

an le

afm

iner

Sou

th A

mer

ican

leaf

-m

iner

/Pot

ato

leaf

min

er

Lirio

myz

a tri

folii

Lirio

myz

a hu

idob

rens

is

Larv

ae tu

nnel

into

leav

es

Larv

ae tu

nnel

into

leav

es

App

ly s

uita

ble

inse

ctic

ide

No

inse

ctic

ide

curr

ently

re

gist

ered

Bea

n flo

wer

thrip

s

Bea

n th

rips

Meg

alur

othr

ips

sjös

tedt

i

Ser

icot

hrip

s oc

cipi

talis

Feed

in fl

ower

s, c

ausi

ng a

roug

hene

d,

silv

ery

text

ure

on p

ods

Feed

in fl

ower

s, c

ausi

ng a

roug

hene

d,

silv

ery

text

ure

on p

ods

App

ly s

uita

ble

inse

ctic

ide

App

ly s

uita

ble

inse

ctic

ide

Bea

n w

eevi

l

Bea

n ga

ll w

eevi

l

Aca

ntho

scel

ides

obt

ectu

s

Alc

idod

es e

ryth

ropt

erus

Larv

ae e

nter

see

d an

d ho

llow

it o

ut b

y fe

edin

g

Larv

ae e

nter

ste

ms,

pup

ate

in th

e ga

lls

form

ed

App

ly s

uita

ble

inse

ctic

ide

App

ly s

uita

ble

inse

ctic

ide

22

ENQUIRIES

For futher information on bean production contact:

z ARC-Grain Crops Institute (ARC–GCI) Private Bag X1251 Potchefstroom 2520 Tel: 018 299 6100

z Dry Bean Producers’ Organisation (DPO) P.O. Box 26269 Arcadia 0007 Tel: 012 325 1850 and subscribe to SA Dry Beans, a quarterly magazine. The Dry Bean Production Manual can also be ordered from the same address.