Leguminous Vegetable Cultivation and Seed Production S ...

Leguminous Vegetable Cultivation and Seed Production
S. Shanmugasundaram
Introduction
Leguminous vegetables have been cultivated for more than 6,000 years in different parts of
the world. Legumes for human consumption constitute about 5% of the cultivated crops. World
production of selected vegetable legumes are given in table 1.
Table 1. Area and
Ve etable
Green peas
Green beans
Dry peas
Dry beans
Soybeans
roduction of selected ve g etable le
Countr / Region Area (ha x 1000)
World
802
Asia
89
World
391
Asia
102
World
8,428
Southeast Asia
27
World
25,959
Southeast Asia
1,437
World
52,600
Asia
7,500
ions and the world
Production (t x 1000)
4,699
144
2,527
636
11,361
22
14,637
1,082
96,000
10,000
In countries like India where majority of the population are vegetarians, leguminous
vegetables serve as the major source of protein in the diet. In developing third world countries,
especially for the' poor, the major protein source in the diet are vegetable legumes. Most
leguminous vegetables are rich in phosphorus, calcium, iron, and a number of essential vitamins;
crops like soybean, groundnut, and Bamabara groundnut are also rich in fats which are needed by
the body to absorb vitamin A. Although leguminous vegetables are deficient in some of the sulfurcontaining
aminoacids, they are well compensated when consumed with cereals. In some instances
the leaves, tender shoots, and roots are harvested and used as vegetables. The whole seed of some
of the legumes are called grain. Seeds of legumes without seed coat and cotyledons split into half
are commonly called as pulses in India. Similarly the split pigeon pea, Cicer arietinuin, L. is
referred to as dal in India and Pakistan. According to Vavilov all the main centers of origin of
cultivated plants have contributed to the cultivated legumes of today.
Legumes are rather unique compared to other vegetables in that they can obtain free
atmospheric nitrogen through their symbiotic association with the nitrogen-fixing bacteria,
Rhizobiwn or Pradyrhizobium, in legume root nodules. The nitrogen fixed in the root nodules are
not only available to the plant but they also enrich the soil, in varying amounts, when the plants
complete their life cycle.
Many leguminous vegetable plants contain toxic substances like trypsin inhibitor
{ (soybean, Glycine max (L.) Merrill)], rotenone (yam bean, Pachyrhizus erosus L.), and
cyanogenic glucoside (hyacinth bean, Lab lab niger L., and Lathyrus sativus L.). There are diverse
ways by which the toxic effects of these vegetables can be eliminated rendering them safe for
human consumption.
1

Depending upon the country some of the legumes are included in the field crops category,
others are included under horticultural crops, while still others are included in the oilseeds crop
group. However, in many of the monographs dealing with vegetable legumes published in
different countries almost all these crops are treated as vegetable crops.
Leguminous vegetables are used as fresh pod, immature seed and mature dry seed, and majority of
these vegetables are also canned and frozen for the market. Some of the legume seeds are sprouted
and are popular in many Asian countries. any legumes are also processed.
In international trade leguminous vegetables play an important role. Dry seeds, canned and
frozen foods, and processed food products from leguminous vegetables enter the international
market where they are important commodities for foreign exchange.
Botany
Legumes are dicotyledonous annuals or perennials. There are about 480 genera and more
than 12,000 species in the family Leguminosae (commonly called the pea family). As a group they
contain at least 28 different vegetable crops belonging to 18 genera. Almost all the vegetable crops
belong to the subfamily Papilionaceae.
When the seeds germinate, in some legumes, the cotyledons remain inside the soil due to
limited elongation of the hypocotyl. Such germination is referred to as hypogeal germination.
Example: peas, Pisum sativuin L. In other instances, as in the case of soybean (Glycine max L.
(Merr.) and common bean (Phaseolus vulgaris L.) the cotyledons are pushed above the soil surface
by the rapid elongation and growth of the hypocotyl. Such germination is called epigeal
germination.
2

A list of leguminous vegetables commonly grown in South and Southeast Asia are given in
table. 2
Table 2. Leguminous vegetables
g own in S
Crop
Botanical name
outh and Southeast Asia.
l iromosome Edible part
no.
Adaptation
Beans
Common, Snap, Phaseolus vulgaris L.
String
22 Immature pod, mature seeds Temp. and tropics
Lima bean P. lunatus L. 22 Green seeds Warm season
Tepary bean P. acutifolius A. Gray 22 Dry beans Dry areas
Adzuki bean Vigna angularis (Wind) Ohwi & 22 Immature pod, mature seeds Warm season
Mungbean, greengram
Ohashi
V. radiata (L.) Wilczek 22 Green pod, mature seeds, Warm season
sprouts
Blackgram, Urd bean V. mungo (L.) Flepper 22 Mature dry seeds
Warm season, dry tropics
Rice bean V. umbellate (Thunb) Ohwi and 22 Mature dry Warm season
Peas
Ohasi
Pist nn sativunl L. 14 Immature, seeds, pods, tender Cool, humid season
Peanut, Groundnut Arachis hypogaea L. 40 Mature seed, tender shoots, and Tropics and subtropics,
leaves
warm temp.
Swordbean Canavalia gladiata (Jacq.) D.C. 22, Young pods and beans Tropics
44,
46
Pigeon pea, redgram Cajanus cajan L. Millsp. 22 Young green pods, seeds, Warm season
mature seeds
Chickpea, Cicer arietinum L. 16 Green pods, tender shoots, dried
Bengalgram
seeds
Cool, dry
Clusterbean, guar Cyamopsis tetragoraoloba (L.) 14 Young tender pods
Dry tropics
Taub.
Soybean
Glycine max (L.) Merr. 40 Immature green seed; mature dry Tropics to 52°N
seed, sprouts
Hyacinth bean, lablab Lab lab purpureus (L.) 22 Young pods, tender bean, dried Dry season
bean
seeds
Grass pea, Chickling Lathyrus sativus L. 14 Seeds, leaves used as herbs Cool season
pea
Lentil Lens culin..aris Medikus 14 Mature seed Winter crop
Yam bean Pachyrhizus erosus Urban 22 Succulent roots Hot, wet tropics,
perennial
Potato bean P. tuberosus spreng 22 Tubers
Perennial
Winged bean Psophocarpus tetragonolobus 18 Almost all parts used Tropical Asia
D.C.
Fenugreek
Trigonella foenum-graecum L. 7 Mature seeds Winter
Faba bean, broad Vicia faba L. 12 Green beans, dry seeds Temp. cool season
bean, Horse bean,
Windsor bean
leaves
Cowpea, Catjang Vigna unguiculata (L.) Walp 22 Immature pods, young shoots, Trop. Africa
dry beans
Yardlong bean, V. sesquipedalis (L.) Walp 22 Immature pods
Warm season
Asparagus bean
Bambara groundnut Vigna subterranea (L.) Walp 22 Immature and mature seeds Tropical Africa
Horsegram Macrotylom.a unifloruin (Lam) 20, Mature seeds Dry tropics
Verde 22
Runner bean Phaseolus coccineus L. 22 Green pods Temperate
Moth bean Vigna aconitifolia (Jacq.) 22 Green pods, dry whole or split Tropical
Marechal
seeds
3

Description of Selected Legumes
L Snap, String, or French Bean
Phaseolus vidgaris likely originated from Central America. It is commonly associated with
corn and squash culture in the tropical Latin American countries. It is an annual with epigeal
germination.
CIAT in Cali, Colombia has classified the world collection of this bean into the following
four main types by growth habit: (1) dwarf determinate, (2) dwarf indeterminate, (3) prostrate
indeterminate, and (4) climbing indeterminate. Beans are also classified according to use as
follows: snap or string beans (for tender fresh pods); green shell beans (green shelled condition,
normally bush and climbing varieties); and dry-shell or field beans (mature dry seeds);
a_lLus
Peas probably originated in Southwest Asia. It is a cool season crop in the subtropics and
also grown at higher altitudes in the tropics.
2, Mungbean
India or the Indo-Burmese region is the origin of mungbean. In South Asia it is one of the
major leguminous vegetable crops. In Southeast Asia it is one of the three main legumes.
4. Vegetable Soybean (Fdamame)
Soybean originated as a domesticate in the eastern half of northern China around the 11th
century BC. It was introduced from China to the USA, Japan, Korea, and South and Southeast
Asian countries at different times.
Large yellow or green-seeded varieties with gray hilum are preferred for use as vegetable
soybeans. Based on latitudinal adaptation soybean cultivars in the USA and Canada have been
classified into 13 maturity groups (MG). MG 000, 00, and 0 are early and adapted to extreme
north latitudes while MG IX and X are late and adapted to tropical latitudes. However, this MG
system breaks down in the tropical and subtropical latitudes.
Controlled Hybridization Procedures
1 . Mun . bean
India has done considerable research on mungbean through their "Pulse Scheme" since
1943. In 1967 an All-India coordinated Pulse Improvement Program commenced with yield and
disease resistance as the primary concerns. A number of varieties have been released (table 3).
4

Table ri beLan cultivars released in India
Ctdtivar name Source/ parents Year Location Improve& Ref.2
(days) characters
"T - ileysiap.0 as selections
Type 1
Muzaffarpur 1948 U.P. 60 G, GM 1
Shining Mung No. 1 Kuhl bung Type 1 Punjab 65 LG, S 2
COI Local 1952 Tamilnadu 135 SG, DL 3
CO2 PLS 365/3 1975 Tamilnadu 65 DG 4
CO3 PLS 367 1976 Tamilnadu 70 SG, IRC 4
BR-2 Bhagalpur Local Bihar 110-115 MG 5
Arndt Bihar Local Bihar 9 0 MY, YMV 5
Khargone-1 K 119-56 M.P. 65 LG, GM 5 _
R-288-8 Local Rajasthan 70-75 SG 5
Krishna-11 Gwalior Local M.P. 65 LG, GM 5
D66-26 Local 1968 Rajasthan 60-65 SG 5
Musa-Baisakhi Type 44 New Delhi 60-65 DG, spring 5
and summer
Kopergaon
Local
1975 Maharashtra 60 SG 6
Developed b bridization and selection
Type 44 Type 1 x Type 49 1948 U.P. 60-65 DG, summer, 7
spring
Type 51 4465-4 x Type 49 1962 U.P. 75-80 SG, mixed 8
crop
Jawahar-45 Madira x UP local 1972 M.P. 75-80 SG, kharif 9
S-8 (Mohini) BR 2 x T2 1972 New Delhi 60-65 SG 10
Kanke Multipurpose Tl x China Moong 1973 SG 11
781
ML 1 Hyb. 45 x 23-67 1973 Punjab 9 0 G, tolerant to 12
KM I S 8 x PS 16 1978 Tamilnadu 65
disease
YMV, pod 5
borer
NM 5 No. 54 x Hyb. 45 Punjab 80-85 G, kharif 5
PS 7 1981 New Delhi 60-65 DG, Summer 5
PS 10 1981 New Delhi 60-65 DG, Summer 5
G = green seed; GM = for green manure; LG = light green seed; SG = shiny green seed; S =
shiny seed; DO = dull seed; DL = dry land; IRC = irrigated conditions; MG = mottled green
seed; MY = mottled yellow; YMV = yellow mosaic virus-tolerant.
2 1 - S.P. Singh 1955; 2 - S.G. Singh 1965; 3 - Premsekar and Srinivasan 1961; 4 -
Rathnaswamy et al. 1977; 5 - D.P. Singh 1982; 6 - Mandoli and Nigam 1966; 7 - Pathak and
Singh 1961; 8 - Pathak et al. 1962; 9 - L. Singh et al. 1972; 10 - S.P. Singh 1972; 11 -
'Bhargava 1973; 12 - S. Singh et al. 1973.
In the Philippines syncrhronized maturity, seasonal adaptation, and high yield along with
disease resistance were emphasized. The Bureau of Plant Industry and the University of the
Philippines Los Banos conduct research and develop new varieties.
Indonesia, Thailand, USA, Sri Lanka, and Australia have mungbean breeding programs
which have released new improved varieties that are high yielding, carry resistance to powdery
mildew and cercospora leaf spot, have synchronized maturity, and large seed size. A list of
varieties from AVRDC materials released in different countries are given in table 4.
5

Table 4. AVRDC mun bean selections released as cultivars in different countries
Cultivar AVRDC no. Year of Country
release
Improved characters'
ASVEG VC 1089-A 1978 Costa Rica HY
B angasa V 3476 1980 Korea HY, UM, LR
Tainan Sel. #3 VC 1628A 1981 Taiwan HY, UM, LR
M 986 VC 156OD 2 1981
India 2
1982 Australia
King V 13882
1982 Australia HY, EM, PW, LR
Station 46 VC 1000-45-B 1982 Fiji HY
Seonhwa Nogdu VC 1973-A 1982 Korea HY, MMV, RPM, (CLS), UM
Type 77 VC 1131-B-12-2B 1982 Sri Lanka HY, MYMV, CR
Manyar VC 1089-A 1983 Indonesia HY, CLS, R
Nuri V 2773 1983 Indonesia HY, (CLS), R
1983 Malaysia 3
Imara V 1380 1983 Tanzania
Station 25 VC 1007-14-1-5B 3 1984 Fiji
Station 27 VC 1160-1-1-2B 3 1983 Fiji
BPI Mg2 VC 1163 1984 Philippines HY, CLS, RPM, R
Xu Yin No. 1 VC 1973-A 1985 China HY, WA
Boliche 451 VC 1163 3 1985 Ecuador
KPS No. 1 VC 1973-A 1985 Thailand
KPS No. 2 VC 2778-A 1985 Thailand
Walet VC 1163-A 1986 Indonesia HY, NS< CLS, 'RPM, TDO, UM
Gelatik VC 1160-22B-1-B 1986 Indonesia HY, NS< CLS, RPM, UM
BPI Mg4 VC 2764-B 1986 Philippines HY, UM, LR, EM, (CLS), RPM
DX 102a VC 2768-A 1986 Vietnam HY, SLS-R, RLD
DX 113 VC 2763-A 1986 Vietnam NY, TASS, RLD
1 HY = high-yielding; UM uniforrn maturing; LR = lodging-resistant; EM = early maturing; PW
= resistant to pod weathering; CLS/(CLS) = resistant/moderately resistant to cercospora leaf
spot; RLD = resistant to local diseases; SLS-R; Sandy loam soil after rice; TDO = tolerant to
damping off; R = rust-resistant; MMV = resistant to mungbean mottle virus; RPM = resistant to
powdery mildew; MYMV = resistant to mungbean yellow mosaic virus; CR = resistant to
charcoal rot; WA = wide adaptability; TASS = tolerant to acidic and saline soils; NS =
nonshattering.
2
3
Adapted selection developed from AVRDC parental stocks.
Reported released but no further information.
Through intensive research efforts at AVRDC in collaboration with national program
scientists the yield potential of mungbean has been improved from 0.5 t/ha to more than 2 t/ha.
Photoperiod insensitivity, multiple disease resistance, large seed size, and synchronized maturity
have been incorporated in improved lines.
2„Ve g etable Soybean
The most popular vegetable soybeans in Japan are predominantly developed by private seed
companies. Among 50 new vegetable soybeans, the most popular ones are: Tzuzunoko, Ryokkoh,
Kegon, Hatsutaka, Taisho Shiroge, Nakate Maori, Suzumo, Enrei, Fukuda, Raityo, Shirobato,
Tamasudare, Hakutyo, Shiratsuyu, and Blue Side.
In Taiwan at present the leading varieties are Kaohsiung No. 1., Tzuzunoko, and
Ryokkoh. Kaohsiung No. 1 (KS #1) is a pureline selection from Taisho Shiroge from Japan done
at AVRDC. Detailed trials and final assessment for release were done by Kaohsiung District

Agricultural Improvement Station (DAIS). KS #1 was released in 1987. In 1988 it occupied 51%
of the total vegetable soybean area in Taiwan. In 1989, it occupied more than 80% of the area.
References
Fehr, W.R. and H.H. Hadley. 1980. Hybridization in crop plants. American Society of
Agronomy. Madison, Wisconsin, USA 765 p.
Gritton, E.T. 1986. Pea Breeding. In: P. 283-319. M.J. Bassett (ed.). Breeding Vegetable Crops.
AVI Publishing Co. Westport, Connecticut, USA.
orton, F., R.E. Smith and J.M. PoehIman. 1982. The Mungbean. University of Puerto Rico,
Mayaguez. 136 p.
Pandita, M.L., and P.S. Pratap. 1986. Peas and Beans. In: P. 469-496. T.K. Bose and M.G.
Som (ed.). Vegetable Crops in India. Maya Prokash, Calcutta-Six.
Parthesarathy, V.A. 1986. French bean. In: P. 497-514. T.K. Bose and M.G. Som. (ed.).
Vegetable Crops in India, Nayo Prokash, Calcutta-Six.
Shanmugasundaram, S. 1988. A catalog of mungbean cultivars released around the world.
AVRDC, Shanhua, Tainan. 20 p.
Shanmugasundaram, S. and B.T. McLean. '1988. Mungbean: Proceedings of the Second
International Symposium. AVRDC, Shanhua, Tainan. 730 p.
Shanmugasundaram, S., S.C.S. Tsou, and S.H. Cheng. 1989. Vegetable soybeans in the East.
In: P. 1979-1986. A.J. Pascale (ed.). World Soybean Research Conference IV.
Shanmugasundaram, S., and J.M. Poehlrnan. 1989. Genetics and breeding of Mungbean. In:
A.K. Mandal (ed.). Genetics and Cytogenetics of Crop Plants.
Sibernagel, M.J. 1986. Snap bean breeding. In: P. 243-282. M.J. Bassett (ed.) Breeding
Vegetable Crops. AVI Publishing Co. Westport, Connecticut, USA.
Van der Maesen, L.J.G. and S. Somoatmadja. 1989. Plant Resources of South-East Asia. Pudoc
Wageningen. 105 p.
Yamaguchi, Mas 1983. World Vegetable. AVI Publishing Co. Westport, Connecticut, 414 p.
7

No-Tillage Rice Stubble Soybean Cultivation (NTRSC)
Many farmers in southern Taiwan have been growing soybean after harvesting rice,
without tilling the land. After producing two rice crops, the farmers are able to grow a third crop of
soybean in the same field. They use minimum resources and earn a reasonable income. This
practice can be easily adopted in other tropical countries where rice-based cropping systems
predominate.
The no-tillage approach for growing soybean after rice with limited resources produce a
high-value soybean crop with low inputs within a short growing season.
Soybean cultivation practiced by farmers in southern Taiwan is presented in the following:
• The no-tillage rice stubble soybean cultivation or N-T-R-S-C can be practiced in a rice-based
cropping system wherever rice is a major crop.
• The farmers in southern Taiwan grow two rice crops from January to September and a third crop
of short duration early maturing soybean from September to December just after harvesting rice
without land tillage.
• After the rice crop is harvested and threshed, the rice straw is bundled and kept in the rows.
e The rice stubbles left after the harvest serve as markers of planting rows for soybean.
• To plant soybean, either a planter is used or a group of men and women are employed for
planting. A bag containing soybean seed is worn around the waist and each person plants about 5
rows at a time. Each individtial plants about 1,000 M2 in one day.
e With the help of a small trowel, a shallow hole (3 to 4 centimeters deep) is made near each rice
stubble and 3-4 seeds are dropped in each hole. The hole is not covered.
• The spacing between and within the row is the same as that for rice, either 22.5 cm by 22.5 cm
or 25 cm by 25 cm.
• Just after planting, a herbicide mixture of alachior at the rate of 1.5-2 kilograms active ingredient
(al.) per hectare plus paraquat 0.75 kg a.i./ha is applied to control weeds.
• The rice straw is then spread on the field. The straw should not be allowed to hang on to the
stubble to prevent shading which could result in lanky and weak seedlings.
• A paddy row marker is used as a roller to press the rice straw close to the ground. The rice straw
mulch conserves moisture and suppresses weed growth.
• In some low-lying areas, the straw is burnt after spreading. Burning of the straw reduces excess
moisture, destroys the weeds, kills some insect pests and their eggs and adds potash to the soil.
e Reduction of soil moisture loosens the soil making it friable, and providing optimum conditions
for seed germination.
• The seedlings emerge easily from the straw mulch.
• A fertilizer mixture containing 20 to 30 kg N + 60 kg P205 + 80 kg K20/ha is prepared and
broadcasted on the mulched field. Or, it may be applied just after burning the straw. In the burnt
field, the quantity of potash is reduced to 50-60 kg/ha.
• You can see the excellent germination in fields with rice straw mulch or on a burnt field.
8

At the seedling stage, the crop is usually attacked by beanflies. The adult beanfly may be found
on the leaf. The beanfly larva or maggot tunnels through the stem and causes the most serious
damage.
To control beanfly, spraying of insecticides such as monocrotophos or omethoate or dimethoate
at the rate of 0.25-0.5 kg a.i./ha 3-4 days after emergence of seedlings is suggested. The spray is
repeated 3 to 4 times or more at weekly intervals depending on insect infestation.
Soybean is attacked by rust disease which may cause serious yield losses. Plant rusttolerant/resistant
cultivars, if available. Fungicides such as mancozeb or triadimefon at 2 kg
a.i./ha can be sprayed against soybean rust. Spray 2 to 3 times as needed. To reduce the cost of
spraying, the fungicide and a compatible insecticide can be mixed and sprayed. If labor is
available, the field may be hand weeded occasionally.
Three to four seeds planted per hole gives a density of about 500,000 to 600,000 plants per
hectare which covers the field very well and also controls weed growth. The crop matures in
about 85 to 100 days. Harvesting is generally done manually.
• The beans are threshed with a locally developed mechanical thresher. Threshed seeds are cleaned
and dried in the sun and marketed.
• The yield of an 85 to 100-day soybean crop is between 1.4 and 3 tons per hectare.
Mungbean Sprout Productioq
Mungbean is an important legume crop extensively cultivated in many developing countries
where a variety of mungbean dishes and other products are prepared. The mungbean sprout is a
traditional vegetable in China and Southeast Asia. However, mungbean sprout is not well known
in South Asia, Africa and most other mungbean-producing countries where a vast potential for its
commercial production, consumption and export exists.
Mungbean sprout production is a simple germination process which requires neither
sunlight nor soil; it has no seasonal limitations. The process is completed in just four to eight days.
The sprout production is extremely inexpensive, requiring only mungbean seeds, sprouting
containers and water as inputs. It can, therefore, be practiced even by poor farmers in augmenting
their meager resources. Mungbean sprouts serve as a good alternative vegetable and source of
income. This is especially true during hot wet summer and rainy seasons when there is acute
shortage of fresh vegetables, or in the event of crop losses due to natural calamities like typhoon,
flood or epidemics of diseases or insect pests.
The potentials of mungbean sprout as a cheap nutritious food and the method of producing
mungbean sprout for domestic use as well as for earning an income are described below:
• Mungbean sprouts cooked alone or mixed with meat or other vegetables provide a fresh and
naturally nutritious dish.
Mungbean sprout production simply involves germination, which can be done indoors
throughout the year. It does not require soil and sunlight.
• The procedure involved in sprout production includes washing, soaking, sprouting, harvesting
and packing.
e Small hard-seeded mungbean often has poor germination and weak sprout growth. Large-seeded
mungbean is also not so economical since they result in lesser sprouts.
9

• Choose good quality, premium grade mungbean seeds of medium size with smooth seed coats.
Remove broken and shriveled seeds. Be sure that beans are not treated with fungicides
or insecticides.
• Store seeds under cool and dry conditions to ensure high seed germination and sprout vigor.
Beans stored under WC and 85% relative humidity produce good quality sprouts. Seeds with
15% moisture can be safely stored for one year at 10 0 C or below.
• Before soaking, wash the seeds in fresh water, stirring vigorously three to four times to allow
the empty, broken and light seeds to float. Remove the floating seeds and debris. Repeat
washing using fresh water every time until the beans are thoroughly cleaned.
. In Taiwan, traditional earthen wares and stone jars are used for sprouting mungbean seeds.
These containers have holes near the bottom to drain out excess water.
• For larger quantity of seeds, use germination tanks of convenient size, preferably lined with tiles.
Wash containers thoroughly with hot water (80 0 C) before use. Big plastic containers will also do
• Arrange and perform all sprouting operations in a sheltered place to protect the sprouts from
light. Darkness ensures bright white and long mungbean sprouts. Moderate temperature (23-
28 0 C) and high humidity (85-90%) in the sprouting room help produce good quality crispy
sprouts.
. After washing, soak the beans in tap water at room temperature for eight hours. In the cool
season, use warm water (32 0 C) for soaking. Put the soaked beans in containers. Do not fill the
containers to more than 75% of their capacity to avoid overflowing when the seeds sprout.
Apply a fine water spray or mist uniformly over the seeds at three-to four-hour intervals during
the hot season Ad six to seven hours during the cool season. Apply just enough water to
keep the sprouts continuously moist without drying.
• A overhead water pipe line fitted with taps and movable water pipe or automatic sprinkler system
connected to a timer are very convenient for watering.
• Stage 1: Beans are swollen after eight hours of soaking.
Stage 2: Seeds start germinating one day after soaking.
Stage 3: Seeds germinate fully two to three days after soaking with 1 to 2 cm-long sprouts.
Stage 4: Sprouts increase in length to 2 to 3-cm after three to four days soaking.
Stage 5: Sprouts attain a length of about 5 cm or more in four to five days of soaking. In most
countries, standard marketable sprouts are at least 5 cm long.
Stage 6: Sprouts grow further, reaching a length of 8 to 9 cm after six to eight days of soaking.
Longer sprouts are preferred by consumers in Taiwan.
• Consumer preferences determine the size of sprouts produced. Relative sprout lengths at
different stages provide a wide choice.
Transfer sprouts of marketable size from the sprouting containers to drums/troughs or buckets
for washing Wash and pack sprouts during early morning to avoid spoilage by high temperature
after sunrise. Remove all broken roots, sprout pieces and other debris while washing.
• Wash with fresh cold water three to four times to separate the seed coats still attached to the
sprouts. Remove the sprouts from the drum using a basket or sieve.

. Use plastic bags to pack the sprouts for the market. A kilogram of dry seed yields around eight to
nine kilograms of sprouts.
. Vendors in the local market usually sell the sprouts in open containers, but sprouts kept this way
are likely to deteriorate quickly. Well-developed market centers/ supermarkets use special
packages laminated with cellophane to prevent drying and quick deterioration. To enhance shelf
life, keep the sprouts refrigerated.
Vegetable Soybean Cultivation
Vegetable soybean is popular in Japan, Korea, China and Taiwan, and consumption is
increasing very rapidly. Although the vegetable-type varieties of soybean are preferred, the greenshelled
beans as well as whole tender green pods of grain soybean can also be used as a vegetable.
Grain soybean is already widely cultivated in many countries of the tropics and subtropics, so the
production of vegetable soybean can be readily adopted. The cultivation practices for vegetable
soybean and grain soybean are similar except that vegetable soybeans are harvested when the pods
are still green and full. Generally, the green seeds of vegetable soybean are larger, more tender and
sweet. Green-shelled beans can be cooked to make a tasty and nutritious meal or snack.
The importance and cultivation practices of vegetable soybean are described below:
. Vegetable soybean, a rich source of vitamin A, and also good source of carbohydrate, protein
and iron, has excellent potential for enriching the human diet. It is more nutritious than vegetable
green peas. The pods of vegetable soybean are harvested when they are still green, just before
the seeds turn yellow.
. The seeds of vegetable soybeans are commonly larger, sweeter and more tender than grain type
soybean. Such green seeds are commonly used in most countries. Even grain soybeans at green
pod stage can be used as a vegetable.
In addition to domestic consumption, vegetable soybean also has export potential. Export market
requirements are:
Hundred seed weight (dry): 30 g;
No. of seeds per pod: 2
Pubescence on pod: gray
Flavor: good
Pod texture after cooking: easy to squeeze
Taste: slightly sweet
Cooking time: short
Frozen vegetable soybeans are popular in supermarkets of Japan and Taiwan.
The best planting date for vegetable soybean differs with season and location depending upon
temperature and daylength. The optimum temperature range for soybean cultivation is 20-30 0 C
with short day length (< 14 hours). However, planting should be avoided at cooler temperatures
during winter. Loam soil with a pH of 6.0-6.5 is suitable for its cultivation, but the field should
be well drained.
At AVRDC, the following suggested cultural management practices are adopted for high yields
of good quality vegetable soybean. You can make modifications to suit local conditions.
Field preparation: Land tillage makes the soil friable for good germination, increases soil
porosity and aeration for healthy plant growth and kills weeds to control weed-crop competition
for soil nutrients, moisture and light. This in turn helps plant productivity. Plow and rototill the
field.
1 1

Basal fertilizer application: Have soil samples analyzed. The fertilizer requirements are
determined on the basis of the soil test. The higher the soil nutrient level, the lesser will be the
quantity of fertilizer needed. To get a good harvest (7-10 tons green pods per hectare) and
maintain soil nutrient status for consistent productivity, a fertilizer mix containing N, P205 and
K20 at the rate of 20-30, 60 and 80 kg/ha respectively is applied by broadcast as a basal dose
and incorporated into the soil with final harrowing and leveling of the field.
Use of Rhizobium inoculation: Usually Rhizobium inoculation is not required in fields
where legumes are cultivated. But newly opened lands need Rhizobium bacteria inoculations at
10 g per kilogram of seed. The use of Rhizobium bacteria culture will promote nodule formation
and nitrogen fixation by the plant roots.
Seedbed preparation: The soil should not be too dry at the time of seed bed preparation.
Inadequate moisture will result in poor seed germination. At AVRDC, we irrigate the field 3-4
days prior to sowing to ensure sufficient moisture in the soil for good germination of seed.
Prepare 20-cm raised beds spaced one meter apart from center of one bed to the center of the
next.
Seed treatment and planting: The seed is' treated with protectant fungicides such as captan or
thiram at 3 g a.i./kg seed for protection against soilborne fungal diseases. Spacing between rows
is 45 cm and between plants 5-10 cm depending upon seed size and season. Two to three seeds
are sown in each hill. However, spacing between rows varies with variety and season. Usually
seeding (60 to 80 kg seed/ha) is regulated to obtain a population of 400,000 plants per hectare.
Sow seeds by hand or by, a hand operated planter.
Top dressing of fertilizer: The first top dressing is done at the rate of 20 kg N + 25 kg K20
per hectare along plant rows at flowering for higher pod set. A second application of 20 kg N per
hectare is done at the beginning of pod filling stage to improve seed size.
Weed controlt At AVRDC, application of alachlor at 1.5 kg a.i./ha either alone or combined
with pendimethalin at 0.75 kg a.i./ha as pre-emergence spray is practiced to control weeds.
Intertillage: Intertillage once or twice is beneficial for aeration of root system and to control
weeds which emerge after the effect of chemical weedicides fades off.
Irrigation: Maintaining proper soil moisture throughout the crop growing season is important
for good quality pods. Usually, first irrigation is needed within a week after sowing under
AVRDC soil conditions. Irrigation is done in furrows. Depending upon weather and soil
moisture conditions, the irrigation is continued at 10-15-day intervals until the pods are well
developed. However, irrigating the crop is essential at critical periods such as flowering and pod
filling stages.
Disease control: Rust may be a serious problem, especially for seed production, causing up to
100% yield loss. Tan, dark brown or reddish brown lesions occur on leaves of rust-affected
plants. None of the commercial cultivars are resistant to rust, but rust-tolerant breeding lines have
been selected at AVRDC. Fungicides such as mancozeb or triadimefon at the rate of 2 kg a.i./ha
are sprayed at 10-day intervals to control rust in susceptible cultivars.
Downy mildew disease commonly occurs during spring and autumn seasons but it does not
generally cause yield reduction. The symptoms are pale green to light yellow spots on the surface
of the leaf. These spots later enlarge into pale to bright yellow lesions. The underside of the leaf
shows white powdery spores. To control downy mildew, plant resistant cultivars. For
susceptible cultivars spray fungicides such as mancozeb at the rate of 2 kg a.i./ha depending
upon severity of disease attack.
2

Bacterial pustule can cause yield losses of up to 40% in vegetable soybean. Early symptoms of
this disease are small pale green lesions which become watersoaked with bacterial ooze that dries
to become white crust on upper/lower leaf surfaces. The best way to control bacterial pustule
disease is by planting resistant varieties.
Insect pest control: Beanfly is a serious pest of soybean. Beanfly larvae feed inside the plant
stem and their damage cannot be recognized easily. Beanfly damage is more severe in relatively
cool season (e.g. during autumn at AVRDC) compared to long dry weather conditions (e.g.
spring at AVRDC) due to lower insect population. Soybean must be protected against beanfly.
For the autumn crop at AVRDC, monocrotophos, omethoate or dimethoate is sprayed at the rate
of 0.5 kg a.i./ha at 3, 7, 14, 21, 28 and 35 days after emergence (DAE). The first three sprays
are very important and should not be delayed. Spraying is stopped at 35 DAE. In spring, usually
there is no serious damage by beanfly.
Pod borers may attack soybean but usually they do not cause significant yield loss under
AVRDC conditions if we use insecticides for beanfly control.
Stink bug commonly occur on vegetable soybeans late in spring and summer season crops. They
do not cause any economic damage under AVRDC conditions. However, if you notice high
population (i.e. 3 to 4 insects per meter rove) uniformly over the entire field in early pod filling
stage, spray insecticides such as fenvalerate at 100 g a.i./ha or deltamethrin at 30-50 g a.i./ha at
weekly intervals till the insect infestation is controlled.
Defoliators feed on leaves. Minor damage does not require insecticide application. However,
when the attack is severe, they can also be controlled by the insecticides used for stink bug
control.
Stop spraying chemicals at least 10 days prior to harvest. Overuse of insecticides or fungicides is
hazardous for human and animal health.
Harvesting: Harvesting is done when 80% of the pods have reached physiological maturity
stage. It may take 65 to 75 days after germination for vegetable soybeans to be ready for harvest
depending upon variety, temperature and weather conditions. The pods are still green. In
Taiwan, harvesting usually begins at midnight when dew and cool temperature help to preserve
the green color and freshness of the vegetable soybeans. When harvested in daytime, the plants
are kept under the shade. The pods are stripped from the plants by hand. Harvesting machines
which can save labor, cost and time are also available.
Grading is important for export of good quality vegetable soybeans. The diseased and insectdamaged
pods and pods with spots and blemishes are sorted out. The good marketable yields
are:
0 pods - 7-10 t/ha, or
green beans - 4-7 t/ha, or
whole plant - 18-25 t/ha
I 3

Seed Production Technology of Garden Peas
S.
Shanrnugasundaram
Garden peas are one of the four most important seed legumes. It occupies an important
place among the winter vegetables in India. In the North Indian hills, it is the most important offseason
vegetable grown both as a summer and autumn crop. It is cultivated in states like
Bihar, TYL9 ' , Aauonn.MoburobLru,Delhi, West Bengal, Punjab, uodHinoaoboJPradesh. The most
important garden pea growing state iu}3.P.which accounts for more than 60 % of production.
In self-pollinated crops like garden pea, hybrid vigor is commonly found when different
purelines are crossed. Since self-polliooUioo is the general rule, inbreeding is necessary to obtain
pozeIiueoin this group of plants.
Whether or not it is economically feasible to use hybrid vigor depends upon the cost of
producing the hybrid seed in relation to the value of the increased yields. Since most self-pollinated
crops produce urclativeln small amount of pollen, which is not transferred by the wind or by
insects to any significant degree, hand pollination is most likely necessary to bring about u1rans{er
of pollen between plants. If many seeds are produced by each hand pollination then the increased
yield justifies hybridization for greenhouse and early market use. With a crop like garden peas, it is
very unlikely that hybrids will ever be used because of difficulty of hand pollination and the small
number of seeds produced per pollination.
The production of quality seeds not only involves the selection of the best and true to type
plants in varieties of different vegetables but also the adoption of specific techniques suited to each
kind. For the production of good quality seeds such information as whether a particular crop is
self-pollinated or cross-polliootcd is absolutely oeceaary,as the technique to be used will depend
on it.
Seed Production
Seeds of garden peas of almost all varieties can be quite efficiently produced in the North
Indian plains. Therefore, there seems to be no real advantage in producing pea seed in the hills for
supplying to the vegetable growers in the plains.
The agronomic practices to be followed for crops raised for seed production are the same as
for those raised for commercial green pod purposes. Some of the important aspects of cultivation
are:
Soil and Climatic Requirements:
Peas can be
in a variety of soils, from light sandy loam to clay though the best
results are achieved on well drained loose, friable loamy soils, and not in acidic soils. The most
favorablepH range is between 6.0 uod7.5.
Peas prefer cool weather; they do not grow well during the intense heat of summer. The
blossoms and pod are more susceptible to frost than the leaves uods1e000.Tbe seeds can germinate
at nroinicunzo temperature of 50C; the optimum temperature for germination is about 220C. At
higher temperatures, germination is rapid but loss of stand may result from various decaying
organiazom.
}

Early varieties can be sown from mid-October to the first week of November while midseason
varieties can be sown from the last week of October to mid-November. Late varieties can be
sown up to the end of November.
Seed Rate:
Use 70 to 75 kg/ha for late varieties and 100 kg/ha for early varieties. For the variety Arkel
the seed rate can be increased up to 125 kg/ha.
Inoculation:
Inoculation of pea seeds with pea nodule bacterium culture is recommended when peas are
planted for the first time and also when the crop is to be grown on poor soil. Emulsify the culture
material in a small quantity of 10 % sugar or gur solution, sufficient to moisten the seed. Heap the
seed on a clean floor and moisten and mix thoroughly with the solution. Then spread moistened
seed in a thin layer in the shade to dry and sow in the field in the evening or on a cloudy day.
Spacing:
Use 30 cm for row-to-row spacing for early and 45 cm for mid-season and late varieties.
Within-row continuous sowing is done and later on the plants can be spaced at adistanoe of 2 to
ljozo.l1labor is cheap and adequate then sowing with odibbler with spikes at 3"x7" distance is
preferred.
Fertilizer Use:
A high dose of nitrogenous fertilizer may have a deleterious effect on nodule formation and
nitrogen fixation. A small dose of nitrogenous fertilizer ( about 25 N/ha ) is necessary to stimulate
early growth ,of legumes. Phosphates increase yield and improve the quality of peas, whereas
potassium appears to increase the yield and nitrogen fixation ability of the legumes. Apply about
20 t FYM/ha, 125 kg CAN/ha or 60-65 kg urea/ha, 420 kg Superphosphate/ha, and 100 kg to
100 kg Murate of Potash /ha during field preparation.
Irrigation:
For proper germination presoaking is advisable. If the soil moisture is less at the time of
sowing, a light irrigation may be necessary after planting to ensure proper germination. Thereafter,
during the dry period, light irrigation may be given at an interval of 10-15 days. One or two
irrigations at the time of flowering and fruit-setting are essential. Light irrigation during frosty
weather is also essential to protect the developing flowers and pods from frost damage. Irrigation
with sprinkler is very much recommended.
Isolation:
Since garden pea is a self-pollinated crop, not much contamination is expected in producing
pure seeds of a variety. Consequently the only isolation necessary is to have a planting space far
enough to prevent mechanical mixtures at planting or harvesting time. However, when producing
the foundation seed, two different varieties should be kept about 20 m.
Roguing:
The term "rogue" as used today applies to any off-type plant. Rogues may originate as a
result of mechanical mixture, volunteer mixture from earlier plantings, natural crossing or
morphological changes caused by mutations.
2

For roguing inspect the pea field at least three, times: (I ) before flowering stage; ( 2 ) during
flowering and fruiting; ( 3 ) during the mature fruit stage.
A high standard of pureness to typ e allows 1 off-type plant in 200 plants. To avoid
volunteer mixtures do not sow seed on land that has been planted to a different strain within the
preceeding two years.
Harvesting and Curing:
Harvest the crop from the time the peas become hard in the pod up to the time they become
completely mature. It takes about 30 days for the peas to sufficiently mature for germination after
they reach their green stage. Put the vines in small bunches to cure for at least 10 days between
harvesting and thrashing to allow the sweat to pass.
Thrashing:
thrasher.
Seed Yield:
Thrash the peas as soon as the plants dry. Thrashing can be done with an ordinary grain
rare.
The seed yield per hectare varies from 1.4 to 2 t. Seed yield as high as 2.5 t are also not
\`
3

Seed Production Technology of Beans
There are 18 types of beans found throughout the world. Of these, French bean (Phaselous
vulgaris L.) lablab beans (Labial) purpureus), cowpea (Vigna sinensis Savi) and cluster bean
(Cno ir &y /n /uboI.. Taub. ) are very common and popularly consumed as green
vegetable in India. Except for cluster bean, the seed of the other three beans is also consumed as
pulse.
All these crops are self-pollinated and exhibit very little heterosis. Also because of the less
number of seeds available in the pods economical commercial hybrid seed production is not
possible. Hybrids can be made by hand emasculation and pollination only 1odevxlope a variety and
for other improvements in the crop. The crops need 50-10 m isolation distance to produce
foundation and certified seeds of two cultivars.
French bean
French bean is grown throughout the world as a green vegetable as well as for dry seed
consumption as pulse. It is a self-pollinated crop with only 2-8% outcrossing.
Climate French bean is uvvaoo-aeugoo crop in the hills but it does not thrive well under
extremely high temperature. It cannot withstand drought as well as very heavy rainfall and frost.
Even though, muoyculLivars are photo-insensitive, certain cultivars develop floral buds only
during short days but would abscise during long days. Suitable soil temperature for good and rapid
germination is 00C. Soil temperature ranging from 18 to 270C induce Rhizoctonia solani
infection in young seedlings. High temperature exceeding 240C for two successive days can cause
ureduction of 2% in the podsqt for each degree of temperature above 240C to 360F ( Davis 1945 ) .
SburnmaeLul. (1983) found that 14-190C temperature and 60-70% humidity in autumn season and
20-250C and 50-70% humidity in spring season ared suitable for better growth and yield.
Techniques for seed production French bean can be grown successfully in sandy loam
soils. Alkaline and acidic soils should be avoided. To raise a good crop use 15-20 t FYM, 20 kg
nitrogen, 60 kg phosphorous, and 60 kg potash. Except for nitrogen, other fertilizers should be
mixed in the soil at the time of last plowing.
Before sowing make sure that the soil contains sufficient moisture to attain better and
quicker germination. Watering just after sowing or before germination results in germination
failure. Seeds take 6 to 7 days at I50C soil temperature to germinate, germination is delayed at
temperature below 150C.
Sow seeds of dwarf types at a distance of 45-60 cm in rows; plant-to-plant distance should
be kept at 15-20 cm. Pole types require 90-I00 cm distance between rows and 30-40 cm between
plants. Nearly 50-55 kg seed for pole type and 75-100 kg seed for bush type are required to sow
one hectare of land.
Apply light irrigation and perform weeding and spraying of insecticide as and when
required. Harvest ripe pods by hand. Dry the pods in the sun and thresh by beating with a stick. If
plants are uprooted then curing must be done at least for 1 week so that pod color turns yellowish.
Remove rotten and broken seeds at seed grading. After proper drying, keep the seed in store.
Cowpea (Vigna
oimuasio L.)
Cowpea is grown throughout India for its long pods as green vegetable, seed as pulse, and
foliage as fodder. When grown for dry seeds, it is known as black eye pea, kaffier pea, China pea,
or southern bean. The cultivars grown for their immature pods are variusly known as asparagus
4

ean, snake bean, and yard-long bean. Cowpea belongs the family Leguminoseae, subfamily
Fabaceae.
Soil and Climate
Cowpeuoan be grown in almost all types of soils. It is a warm-season
crop and thrives best between 21 and 350C. It can be grown successfully in spring summer and
rainy season in the North Indian plains. It cannot withstand heavy rainfall and water-logging.
D ifferent cultivars respond differently to temperature and daylength and thus these are distinct
cultivars for spring summer and rainy season.
Seed Production Techniques
Season and Sowing Cowpea can be grown in spring summer and rainy season. In
locations where the climate is mild, it can be grown almost throughout the year, but otherwise
photo-insensitive cultivars are grown. In India it is usually sown in February/March in the
Northern plains and in December/January in the South for spring summer crop; for rainy season
crop, sowing is done in June/July all over the Indian plains.
Sowing is done in well prepared fields by broadcasting seeds or in line sowing. Usually
15-20 kg of seed is required for sowing on 1 hectare depending on cultivar and season. Sowing in
lines facilitate better interculture operations and after care. Line sowing can be done by a drill
operated by a tractor, bullocks or manual labor. Spacing between rows should be 45-60 cm and
between plants 10-15 cm. In case of seed crop, land in which one cultivar of cowpea was grown
the previous year should not be used for growing another cultivars the following year to avoid
contaminations.
Interculture Being a leguminous crop cowpea does not require heavy fertilization. Inoculate
seed with Rhizobium culture before sowing. Application of 10-20 kg N, 50-70 kg phosphorous,
and 50-70 kg potash has been recommended by Chauhan (1972 ) .
Cowpea is a shallow-rooted crop and requires less moisture and light irrigation for proper
growth, as it is sensitive to waterlogging. Irrigation prior to flowering helps in pod setting; another
irrigation should be given after the pods have set. At least one hoeing/weeding after 4 weeks helps
control weeds and in root nodulation. Spraying Maleic hydrazide ( MH) at 50-200 ppm just before
flowering was reported to increase the yield of pod ( Choudhury and Ramphal 1960 ) .
Maintain an isolation distance of 50 nuDor foundation seed and 25 nu for the production of
certified seed between two cultivars ( Anon. 1971). Ripe and dry pods are harvested by hand
picking or by cutting the plants in case of last flush. To avoid shattering of the seeds, harvest when
half to two-thirds of the pod has matured. Some cultivars shatter more than others. This problem is
not encountered in ouldvacuwith flashy inflated pods. Threshing is done by beating widha stick or
by a thresher. Extreme care should be taken during threshing to prevent injury l to1heueod.Tbe
seeds maintain viability for two years under normal storage conditions.
Labial) Beans
Lablab beans are self-pollinated and partially cross-pollinated by insects. Different cultivars
should be grown 50 roapart in case of foundation seed ud25roapart in case of certified seed.
Lablab beans are indeterminate in response ionho1operiod and there are some short-day and longd
types. Lablab bean is a relatively cool season crop adapted to tropical and subtropical regions.
Drought-resistant strains are available and grown as a dry land crop in regions with minimum
rainfall. Fruiting starts at the onset of winter and continues throughout the year. Lablab beans are
grown both for green pods as well as dry seeds. Heterosis may not be of much use in this crop but
cross-combinations showing heterosis vigor can be used to develop high-yielding purelines.
Seed Production Techniques i~ahlabbeans are annuals of bushy or vining type. When the
vines are supported they may grow as high as 6-10 m. They are usaully grown as oso{e crop with
5

staking of the vines. In some places they are grown as a mixed crop with ragi, bajra or sorghum. It
is planted with a distance of about 1 m between crops. The ear heads of the intercrops are
harvested first leaving the stalks as support to the vines. The vines grow on them perfectly. If it is
grown as a sole crop it can be sown with a distance of 2.5 x 1.5 m. Three to four seeds are sown
per hill and one or two plants allowed to grow on each hill. Dwarf types can be grown at a distance
of 1.0 x 0.75 m line to line and plant to plant. About 20-30 kg seed are required to sow 1 ha of
bush type and 10-12 kg for climbing types.
Lablab beans can be grown in a wide range of soils of average fertility. About 20 kg N,
40 kg phosphorus, and 5-6 t FYM are required to grow a good crop in 1 ha of land.
Intercultivation can be done to control the weeds until vines spread between rows. Since lablab
beans cannot stand waterlogging, frequent irrigations should be avoided.
Ripe mature pods can be handpicked from the standing crop. Threshing can be done by
beating the pods with a stick, moving a stone roller over the pods, or under letting bullocks trample
them. Seed should be thoroughly cleaned and dried before bagging. Average seed yield is 6-
8 qt/ha.
Cluster Bean
The tender pods are used as a vegetable and in the southern part of India they are
dehydrated and stored for use. Cluster bean is a self-pollinated crop, yet some outcrossing, i.e. 2%
has been reported. Thus, lesser heterosis is available. Due to less seeds in each pod, economical
commercial hybrid seed production in cluster bean is not possible.
Seed Production Techniques The crop should be sown in well-drained sandy loam soil.
Cluster bean can also tolerate saline and moderately alkaline soils with pH ranging 7.5 to 8.0. It
prefers warm climates and can also be grown in subtropical areas during summer. It prefers longday
conditions for growth and short day for induction of flowering.
Main a row-to-row distance of 45-60 cm and plant-to-plant spacing of 10-15 cm. Seed rate
for line sowing is 15 kg/ha. To improve seed yield, 10-12 kg N, 50-70 kg P, and 50-70 kg K/ha
are recommended. One or two irrigations are needed in case rains are delayed.
Pull out the plants from the field after proper maturity of the pods. Keep the plants in the
leap for curing and proper drying for at least one week. Threshing should be done as in the other
beans. Store the seeds after proper grading and drying. The average seed yield per hectare is
10 qtl.
Pests of Beans
a.
b.
c.
d
ė.
f.
g.
h.
J -
Aphids (Aphis sp.)
Jassid (Amrasca kerni)
Galerucide beetle (Madurasia obscurella)
Pod borer (Adisura sp. Heliothis arinigera)
Bean weevil (Callosobruchus sp.)
Lygacid bug (Chauliops fallax)
Hairy caterpillar (Ascotis imparata)
Stem fly (Ophiomyia phaseoli)
Root weevil (Stiona lineal:0
Bean lady bird beetle (Epilachna varivestis)
6

Disease of Beans
a.
b.
d.
g.
Anthracnose (Colletotrichum lindemuthianum) Fungal
Bean rust (Uromyces appendiculatus) Fungal
Leaf spot (Cercospora mien/a) Fungal
Powdery mildew (Etysiphe polygoni) Fungal
Dry root rot and ashy grey blight and wilt and Charcoal rot (Fusarium solani f. sp. phaseoli)
Fungal
Bacterial blight (Xanthomonas phaseoli) Bacterial
BCMV (Bean common mosaic virus )Viral
owed:
a. Anthracnose (Colletotrichum lindeinuthianuin) Fungal
b. Dieback (Colletotrichum capsici Syd. Fungal)
c. Ashy stem blight (Macmphomhia phaseolina) Fungal
d. Powdery mildew (Erysiphe polygoni DC) Fungal
e. Bacterial blight (Xanthomonas vignicola Bunk) Fungal
e. Mosaic virus virus
Cluster bean:
a. Wilt (Fusariuin sp.)
b. Bacterial blight (Xanthomonas cyamopsidis)
c. Powdery mildew (Leveillula taurica)
d. Anthracnose (Colletotrichunm sp.)
Lab-Lab beans:
a. Leaf spot (Cercospora dolichii Ell.) Fungal
b. Powdery mildew (Leveillula taurica) Fungal
c. Yellow mosaic virus
7

Proceedings of a symposium
on sustainable agriculture
The Role of Green Manure crops
in Rice Farming Systems
25 - 29 May 1987
1988 .
The International Rice Research Institute
in collaboration with
The Commission on the Application of Science
to Agriculture, Forestry, and Aquaculture

The International Rice Research Institute (IRRI) was established in 1960 by the
Ford and Rockefeller Foundations with the help and approval of the Government
of the Philippines. Today IRRI is one of the 13 nonprofit international research
and training centers supported by the Consultative Group on International
Agricultural Research (CGIAR). The CGIAR is sponsored by the Food and
Agriculture Organization (FAO) of the United Nations, the International Bank for
Reconstruction and Development (World Bank), and the United Nations Development
Programme (UNDP). The CGIAR consists of 50 donor countries, international
and regional organizations, and private foundations.
I RRI receives support, through the CGIAR, from a number of donors
including the Asian Development Bank, the European Economic Community, the
Ford Foundation, the International Development Research Centre, the International
Fund for Agricultural Development, the OPEC Special Fund, the
Rockefeller Foundation, the United Nations Development Programme, the
World Bank, and the international aid agencies of the following governments:
Australia, Belgium, Canada, China, Denmark, Finland, France, Federal Republic
of Germany, India, Italy, `Japan, Mexico, The Netherlands, New Zealand,
Norway, the Philippines, Saudi Arabia, Spain, Sweden, Switzerland, United
Kingdom, and United States.
The responsibility for this publication rests with the International Rice
Research Institute.
Copyright © International Rice Research Institute 1988
All rights reserved. Except for quotations of short passages for the purpose of
criticism and review, no part of this publication may be reproduced, stored in
retrieval systems, or transmitted in any form or by any means, electronic,
mechanical, photocopying, recording, or otherwise, without prior permission of
I RRI. This permission will not be unreasonably withheld for use for noncommercial
purposes. IRRI does not require payment for the noncommercial use
of its published works, and hopes that this copyright declaration will not diminish
the bona fide use of its research findings in agricultural research and development.
The designations employed and the presentation of the material in this
publication do not imply the expression of any opinion whatsoever on the part of
IRRI concerning the legal status of any country, territory, city, or area, or of its
authorities, or the delimitation of its frontiers or boundaries.
ISBN 97-104-189-8

Contents
Foreword
Symposium recommendations
KNOWLEDGE AND TECHNOLOGY
Economic feasibility of green manure in rice-based cropping
systems 11
M.W. Rosegrant and Roumasset
Woody species as green manure crops in rice-based cropping
systems 29
J.L. Brewbaker and N. Glover
Green manure in rice the Japan experience 45
M. Ishikawa
Green manure cultivation and use for rice in China 63
Chen Lizhi
Green rn'anure crops in irrigated and rainfed lowland rice-based
cropping systems in South Asia 71
I.P. Abrol and S.P. Palaniappan
Potential of sesbania as a green manure in saline rice soils in
Thailand 83
S. Arunin, C. Dissataporn, Y. Anuluxtipan, and D. Nana
Stem-nodulating legumes as green manure for rice in West Africa
G. Rinaudo, D. Alazard, and A. Moudiongui
Farm-level management systems for green manure crops in Asian rice
environments 111
D.P. Garrity and J.C. Flinn
EFFECTS ON SOIL FERTILITY
Microbiological aspects of green manure in lowland rice soils 131
N.S. SubbaRao
Effect of green manure on soil organic matter content and nitrogen
availability 151
D.R. Bouldin
Nitrogen fixation by leguminous green manure and practices for its
enhancement in tropical lowland rice 165
J.K. Ladha, I. Watanabe, and S. Saono

Role of green manure in low-input farming in the humid tropics
J. van der Heide
Transformation of green manure nitrogen in lowland rice soils
S. Nagarajah
Green manure management in rice-based cropping systems
O.P. Meelu and R.A. Morris
Measurement of nitrogen fixation in crop and shrub legumes 223
M.B. Peoples, D.F. Herridge, and F.J. Bergersen
ACIAR-sponsored legume research 239
E.S. Wallis and D.E. Byth
Effect of green manure on rice soil fertility in the United States 257
M.P. Westcott and D.S. Mikkelsen
Effect of green manure on physicochemical properties of irrigated rice
soils 275
Wen Qixiao and Yu Tianren
INTEGRATED USE OF LEGUMES
Annual legumes for food and as green manure in a rice-based cropping
system 289
K.R. Kulkarni and R.K. Pandey
Use of perennial legumes in Asian farming systems 301
P.K.RrNair
Integrated use of green manure in ricefields in South China 319
Liu Chungchu
Use of green manure in rice farming systems in West and Northwest
Cameroon 333
A.C. Roy, S.B.C. Wanki, and J.A. Takow
GERMPLASM COLLECTION AND SEED
PRODUCTION
Collection and evaluation of tropical legume germplasm 343
R. Schultze-Kraft
Seed production and management of mungbean and soybean 359
S. Shanmugasundaram
Participants 376
209
193
185

Seed pro u t on and mana e ent
of .ungb an n soybean
S. Shanmugasundaram
The seed requirement to plant the world mungbean area is estimated to be
around 68,000 t; for soybean, it is ,156,000t. Current seed supplies cannot
meet that demand. The need to produce sufficient quality seeds in
mungbean and soybean is emphasized and preharvest and postharvest seed
production problems discussed. Future directions for seed production are
examined in the context of innovative concepts and procedures in plant
breeding.
In early agriculture, people grew crops primarily for food.. Each season, they saved
some grain as seed for the next crop. Today, farmers in many countries still follow
that age-old practice. In choosing seeds for the next planting, farmers select only the
best (Chin 1969).
Mungbean Vigna radiata (L.) Wilczek and soybean Glycine max (L.) Merr.
form important constituents of human food and animal feed. It is estimated that
worldwide mungbean production amounts to about 1.4 million t harvested from
about 3.4 million ha (Shanmugasundaram and Poehlman 1988). Seed rate for
planting varies with seed size, percentage of germination, and desired plant
population density (Morton et al 1982). However, 68,000 t of seeds are required to
satisfy the need of 3.4 million ha of mungbean production. Assuming an average
seed rate of 20 kg/ha, about 113,333 ha of land is needed to produce 600 kg good
quality seed/ha.
In 1985, 52.6 million ha were planted to soybean (Table 1), about 49% of the
area in North and Central America, 27% in South America, and 20% in Asia. With
an average seed rate of 60 kg/ ha, it is estimated that 3,156,000 t of seeds are needed.
About 2,104,000 ha of land is required to produce an average 1.5 t good quality
seed/ ha.
The objective in seed production is to maximize the production of seed with
suitable germination capacity (Bowring et al 1978). In the United States in 1983,
certified soybean seed was produced on 387,445 ha, 36% of the total soybean area.
The soybean seed requirement in Thailand was 7,000 t in 1983, but the government
produced only 980 t (Potan 1987). In Indonesia, only 30% of the total area is planted
with seeds of improved cultivars (Djauhari et al 1984).

36 2 GREEN MANURE IN RICE FARMING
tropics and subtropics has received attention (Dassou and Kueneman 1984,
Kueneman 1983, Opefia et al 1987, Shanmugasundaram 1976, Shanmugasundaram
and Poehlman 1988).
Successful quality seed production will depend on incorporation of genetically
controlled quality traits with desirable agronomic ones. I-lard seeded ness is known
to improve seed resistance to detrimental environmental influences (Potts et al
1978). Other characters with similar influences are seed coat thickness (Caviness and
Simpson 1974), pod thickness or composition (Hartwig and Edwards 1970), and
resistance to seedborne diseases (Wilcox et al 1975).
In the past decade, a number of new mungbean and soybean varieties were
released to farmers. But seed quality characters have yet to be incorporated into new
varieties.
Seed categories
Genetic improvement must be associated with good seed certification. Farmers
should have access to good, relatively affordable seed (Walker 1980). But seed
production, inspection, certification, processing, distribution, and marketing vary
widely among countries.
The steps to produce the various categories of seeds described here apply to
mungbean and soybean. Seed multiplication rates vary with the crop.
The plant breeder carefully selects for various traits (with adaptability and high
yield considered essential) and identifies a line as suitable for release. The identified
line is unique in a number of qualitative and quantitative traits. However, certain
distinct traits are uniform and stable. These distinguishing characters are consistent
and relatively easy to use for a specified region of adaptation.
For example, when a new soybean variety is released in the USA, characters
such as seed coat color, hilum color, flower color, pubescence color, stem
termination, leaf type, USA maturity group classification, pertinent disease
resistance or susceptibility, and protein and oil content are described. Foundation
seed is produced from the basic breeder seed. Registered and certified seeds are
produced by selected farmers. Methods of seed production by the plant breeder,
maintainer, seed merchant, and progressive farmer depend on the crop species and
on the breeding system (Bowring et al 1978).
The plant breeder's responsibility is to maintain the pedigree seed (Fehr 1978)
or the prebasic seed (Bowring et al 1978). Basic seed is produced from pedigree seed.
A plant breeder supervises production of these two seed categories of seed, making
sure that the variety is pure and free from variations that are not described as part of
the variety. Pedigree and basic seed also should be free from weed seeds and
extraneous materials.
A variant is defined as plants or seeds described as part of the variety, but
different from the norm for the variety (Otto 1985). In soybean, natural mutation
can cause changes in plant or seed characteristics. Brown and black seed coat
mutants are common in yellow seeded soybean; these offtypes should be removed
during purification (Fehr 1978).

SEED PRODUCTION AND MANAGEMENT OF MUNGBEAN AND SOYBEAN 363
Mungbean and soybean are self-pollinated, annual species reproduced by
normal fertilization. In mungbean, natural outcrossing varies from 0.0 to 13%
(Shanmugasundaram and Poehlman 1988). A high level of outcrossing can cause
considerable variation in the seed produced. In India, when rnungbean seed was
produced, a 1.5-m border was left unharvested between adjacent varieties (Kernick
1961). Considering the large extent of outcrossing in some genotypes, the isolation
requirement has been increased to 3 m.
Usually, a plant breeder maintains a variety by planting single plant progeny
and checking characteristics against the variety's official description. If the rows are
uniform, they are bulked. In soybean, 30-50 kg of pedigree seed normally is reserved.
In rnungbean, .10-15 kg of pedigree seed is reserved. In temperate and tropical
countries, seed production rates vary because of the length of growing seasons and
the yield potential of varieties. Pedigree seed is planted on 0.5-1.5 ha to produce 1-3 t
soybean and 0.3-1 t rnungbean basic seed.
Basic seed is used to produce the subsequent categories of seeds (Shanrnugasundaram
1982). At each stage, care is exercised to remove variants. In countries
with official seed certification programs, designated agencies supervise and regulate
seed certification.
In India, a parastatal national seed corporation coordinates the production of
certified seed through a series. of state seed farms that are profit-responsible. They
were set up and funded by World Bank (Walker 1980). The All-India Coordinated
Research Project on Soybean, in its annual meeting, allocates to each breeder the
quantity of seed to be produced. For example, in 1985-86 breeders produced about
92 t of basic seed of 20 new soybean varieties (P. S. Bhatnagar, pers. comm.).
Factors to consider in seed production
Seed production is a specialized activity. Preharvest and postharvest factors must be
considered (Nangju et al 1978): field environment, cultural practices, genetic
influence, and harvest time (Tekrony et al 1978) and biotic and abiotic factors
(Roberts 1972b, Sinclair and Jackobs 1982).
Basic constraints in seed production can be varietal (genetic characteristics),
environmental, biological, and socioeconomic, alone or in combination. Vagaries of
climate and soils must not be used as excuses for deficiencies in plant genetics,
selection procedures, isolation distances, good crop management, and quality
control (Walker 1980).
Constraints such as photoperiod, temperature, soil properties, and rainfall
cannot be controlled by the seed producer (Shanmugasundaram and Tsou 1987).
Land preparation, organic or inorganic fertilizer applications, pest and disease
control, and weed control and management are factors that can be regulated. A
sufficient knowledge pool is available (for a review see Morton et al 1982, Nangju et
al 1978, Scott and Aldrich 1970, Shanmugasundaram 1982, Shanmugasundaram
and Tsou 1987, Sinclair and Jackobs 1982, Tekrony et al 1978). Although obtaining
a high yield is a consideration, the most important criterion is producing good

36 4 GREEN MANURE IN RICE FARMING
quality seed. Since the price of seed is generally higher than the price of grain, extra
management inputs are justified.
Preharvest factors
Seed longevity and field weathering. At the Asian Vegetable Research and
Development Center ( AVRDC ) , soybean can be planted in the February, July, and
Scptonuberseasons. TbcFebruary crop encounters rain at harvest (Fig.|).The July
rainy season crop may be exposed to typhoons. Field weathering of seed is a
common problem in both seasons. Therefore, the seed quality of February and July
season crops generally is not dependable. The September season CrOp produces the
best quality seed (Sb0000ugasuoduranuaod Tsou 1987 ) . The seed quality of rainy
season crops, in general, is poor in
'
Indonesia, Thailand, Philippines, Sri Lanka, and
Nigeria(Arulnaudhy 1987, Nau uut al 1978, Potan 1987, Sumarno 1987).
One of the best ways to prolong seed longevity and combat field weathering of
soybean is through genetics. At the International Institute of Tropical Agriculture
/llT/\\ and at AVRDC, obtaining good seed quality is a key breeding objective.
Varietal differences in seed deterioration in storage a*c was
vo observed ' ino soybean
(Wien and Kucocnouo1981). Freshly harvested seeds of /\[}S 2, a pure line from an
Indonesian introduction; [`&/ from India; and /\[}S 29 from AVRDC maintained
about 80% germination for about 6 . mo at ambient room temperature in Bangladesh.
Locally grown variety Bragg and /\[}S 66 from AVRDC can be stored for only 2-3
mo (Fig. 2). Small-seeded varieties from Indonesia and black seed coat varieties
deteriorate more slowly than large-seeded varieties. However, reports on the role of
large and small seeds in seed longevity, germination, emergence, and yields have
Temperature (OC)
Precipitation (mm)
40 1 1700
600
30
500
20
400
300
10
200
100
0
J F M A M J J A S 0 N D
Month
I. Maximum and minimum temperature and rainfall pattern at AVR DC in 1984 and time of planting and
harvest.
0

SEED PRODUCTION AND MANAGEMENT OF MUNGBEAN AND SOYBEAN 365
been contradictory (Edwards and Hartwig 1971, Fontes and Ohlrogge 1972, Green
et al 1965, Johnson and Luedders 1974, Ndunguru and Summerfield 1975). Some
changes associated with seed deterioration are reduced protein synthesis, reduced
ability to utilize labeled glucose, reduced respiration, and increased respiration
quotient (A. Knapp, pers. comm.). Although small seeds are associated with better
seed longevity, the reasons are not yet understood.
Seed vigor is an elusive and complex concept.Vigorous seeds are "likely to .. .
perform particularly well in the field, better than others which may be equally
satisfactory in the laboratory test" (Heydecker 1972). Loss of seed vigor due to
weathering precedes loss of seed viability. Assessing seed vigor is problematic for
seedmen (Kuenernan 1982). The concept of seed vigor and its importance to seed
production were described by Heydecker (1972) and Perry (1978). A modified
accelerated aging and hot water stress test were used to screen for seed longevity and
vigor.
In the accelerated aging stress test, seeds are kept at 42 °C and 100% relative
humidity (RH) for 48 h, followed by a laboratory germination test (Byrd and
Delouche 1971). To distinguish cultivars with good and pOOr seed storability, Wien
and Kueneman (1981) used a modified accelerated aging stress technique. After pods
dried, they threshed the seeds and subjected them to 75% RH at 40 °C for 6 wk,
followed by a laboratory germination test.
Germination (%)
100 -
80
60
40
0 AGS 2
AGS 29
V AGS 66
V AGS 129
0 Pb-l(check)
Bragg (check)
20
1 Jan 1 Mar 1 Apr 1 May 15 May 1 Jun 15 Jun 1 Jul
Date of germination test
2. Germination percentage of 6 soybean varieties evaluated at different intervals after storage at ambient
temperature. Bangladesh, 1985.

m
366 GREEN MANURE IN RICE FARMING
Hot water pregermination stress includes soaking seeds for 70 s in 75 'C water
and rinsing in tap water prior to determining germination or emergence (Kueneman
( g 82).
Kueocooan(] q 83 ) evaluated the F I seeds of reciprocal crosses between soybean
genotypes with good and poor seed longevity using the accelerated aging method.
He found significant reciprocal differences, and suggested the possible influence of
the maternal plant genome on seed longevity. The pooled F 2 variances were larger
than pooled parental variances, which indicated the influence of the genotypes.
Differences between reciprocals of the F 2
seed, although relatively small compared
to those between F, reciprocals, were significant, indicating that cytoplasmic gene
action for seed longevity may also be involved, but its effects are probably small.
Because of the influence of the maternal plant, expression of segregation is delayed
one geoeratioo(Koeoeouau 1983). `
Dassou and Kueneman (1984 ) subjected physiologically mature pods to a
weathering technique in an incubator a{30 °C and 90-95 % relative humidity ( RH )
for 10 d. They identified several genotypes resistant to both seed weathering and
deterioration in storage ( Table 3 ) . Paschal and Ellis ( 1978 ) reported that genotypes
PI 205912, P1 205907, [»[ 341249, PI 279088, and {/1 219653 could be used for
breeding soybean with resistance to field weathering and to seed deterioration in
storage.
An early-maturing variety can be used to avoid weathering damage. In Taiwan,
for example, spring soybean is planted in February-March and harvested in roid-
May.Hovvovez `
early maturity is not a dependable alternative. In some years, rains
may come early and spoil the crop.
Manipulating the cropping pattern also can be used to avoid field weathering in
the rainy season. In Pakistan, soybean for seed is planted July-August and harvested
October-November (Beg 1987). In East Java, Indonesia, lowland and upland
soybeans are planted year-round. Seed for the lowland rainy season and dry season
Table 3. Genotypes resistant to seed weathering and to deterioration in storage.
Genotype
Origin
1 00'noed Seed
wt (g) color
Hard After incubator After ambient
seed a weathering storageb
I NDO 153 Indonesia
IPA DO 131 Indonesia
I P4 DO 243P Indonesia
1 WOD226 Indonesia
104 DO 255 Indonesia
INDO 173A Indonesia
Fort Lamy USA
Lee A
USA
Biloxi 3 China
AVRDC 8457 Taiwan
9.7 Black 36.0 54.2 87
10.2 Black 24.6 35.4 92
8.9 Black 17.2 42.9 90
9.3 Black 27.2 46.2 80
10.1 Black 30.6 32.6 91
1 0.8 Black 52.6 32.9 81
10.5 Black 46.6 56.2 80
9.0 Black 62.0 58.5 88
10.5 Black 37.2 50.4 71
6.1 Black 64.0 58.7 77
Source: O0000uond Kueneman 1984.
Nonimbibino seed after 1 h soaking in water.
humidity.
Stored forO mo at 25 0 C and 50 to 95% relative

SEED PRODUCTION AND MANAGEMENT OF MUNGBEAN AND SOYBEAN 367
crops comes from the second upland dry season crop. Seed for the second dry season
crop comes from the first dry season crop. Only the grain of the rainy season crop is
used ( Fig. 3). Similar seed production strategies are used in other countries ( Potan
1987,Sncnarno 1987).
Water management. Water management is closely associated with field
weathering in both soybean and rnungbcaooeed production ( Huck and Davis 1976,
Morton et al 1982). Soybean that undergoes alternate wetting and drying in the field
has poor seed quality caused by rapid differential absorption of water by localized
tissues in the seed coat
(Moore 1971, 1972). Plasmolysis and deplummoo\ysia at
different stages of seed development can result in external and internal seed injuries
(Min / 1957). Damage caused by on-and-off i
` z*
excess moisture also has been observed in
rouogbeao(it C. Imrie, pers. comm. ) . Overhead sprinkler irrigation and rain at
harvest can cause wetting and drying of pods. Therefore, from the R 5
growth stage
on, either flood or furrow irrigation is suggested to obtain good quality seeds.
During the dry season, when good quality seeds can be produced, adequate soil
moisture at flowering (IR | and R 2 ) and seed filling ( R 5 and R6) ( Fehr and Caviness
1977 ) is essential.
Location. Some locations are more suitable for good quality seed production
than others. Low relative humidity and cooler temperatures are the two key factors
to consider in selecting a location for soybean seed production ( Harrington 1963 ) .
Moogbeunis a hot weather crop, but humidity and rainfall should be low for good
quality seed production (Morton et al 1982 ) . Locations with a cool, dry season are
excellent for soybean seed production. In Pakistan, the cooler foothills of Hazara,
Swat, and Parachinar are excellent sites for soybean seed production. Seed
Local
variety
VMS
Dry season 1 Dry season 2
Local variety
3. Flow of soybean seed between locations in different seasons in East Java, Indonesia ( source: personal
discussions with farmers, extension staff, and researchers ) . The arrows show seed flow.

36 8 GREEN MANURE RICE FARMING
produced in those areas is distributed to other areas (Beg 1987). In Indonesia,
soybean seed is produced during the dry season in Sumatra and transported to Java
for planting. Distance, mode of transportation, type of packing material, and
handling are important considerations in seed quality.
Pest management. Because seed is a high value crop, seed quality is an
important consideration. In seed production, weed, insect, and disease control using
recommended management practices is mandatory. Weeds can compete with a crop
and restrict the use of nutrients, reducing crop quality. Weeds can also harbor insect
vectors that may transmit various virus diseases and can serve as hosts for various
fungal and bacterial diseases. Many leguminous weeds are hosts for soybean rust
Phakopsora pachyrhizi and can serve as a reservoir of initial inoculum to create
epidemics on soybean. If the field is weedy, the seeds can be contaminated with weed
seeds during harvest (Nangju et al 1978).
The stink bug Nezara viridu/a in soybean and various pod borers in rnungbe"an
and soybean can reduce seed quality (Morton et al 1982, Todd 1982). The beanfly
A/felanagronomyza sp. and others can reduce seedling vigor and impair seed quality.
It is imperative to monitor insect pest incidence and adopt appropriate, timely
control measures.
Christensen (1972) tested thousands of soybean and seed samples over 20 yr to
determine storage fungi invasion-of seeds prior to harvest. He concluded that there is
no significant invasion of seeds by storage fungi.
Fungal pathogens that can cause a reduction in seed quality in soybean are pod
and stem blight and seed decay Phomopsis spp. = Diaporthe phaseolorum var.
sojae; anthracnose Coiletotrichunl dematium var. truncata; and purple seed stain
('ercospora kikuchii (Sinclair 1982). In the absence of genetic resistance, chemical
control of these diseases is important.
Among the soybean viruses, soybean mosaic virus (SMV), tobacco ringspot
virus (TRSV), and tobacco streak virus (TSV) may be important (Sinclair and
Shurtleff 1975). In mungbean, yellow mosaic virus (YMV) is the most important
virus disease. Vector control and planting resistant varieties are the only means of
controlling virus diseases.
Postharvest factors
A seed begins its existence well before it is harvested. Preharvest conditions can
cause varying amounts of seed deterioration even before harvest (Roberts 1972a).
Harvesting and drying
Within a season, the time of harvest can affect seed viability (Roberts 1972a).
Harvesting should be done promptly on maturity. Harvesting seed with excessive
moisture or too low moisture content can also damage quality. If the crop has to be
harvested before full maturity, but after physiological maturity, it should be dried
slowly under moderate temperature. Slow drying prevents shriveling due to rapid
loss of moisture. After physiological maturity, seeds of both soybean and mungbean
may begin to sprout during the rainy season while the plants are still in the field.

SEED PRODUCTION AND MANAGEMENT OF MUNGBEAN AND SOYBEAN 369
Under those circumstances, it is better to harvest at the onset of rain and dry the
plants in a well-ventilated area. They can be air-dried slowly to enable threshing
later.
Threshing and cleaning
High cylinder speeds of combines or threshers will result in multiple fractures and
deep-seated bruises, especially in large-seeded soybean or mungbean and in seeds
with lower moisture content (Moore 1957, 1972; Roberts 1972a). A 700 rpm cylinder
speed is better than 1155 rpm. Soybean seeds impacted at 12-16% seed moisture
germinated satisfactorily; those impacted at 8-10% and 18-20% moisture germinated
poorly (Bunch 1960).
In developing countries, soybean and mungbean usually are threshed by hand,
either by beating pods inside a bag with sticks or by trampling with animals or small
tractors. Such harsh treatment can result in mutilated seeds. Studies at IITA showed
that combine threshing is inferior to hand threshing and beating pods inside a bag
(Nangju et al 1978). Possibly the cylinder speed was not set properly or the seed
moisture content at threshing was too low.
After threshing, the seeds should be cleaned to remove plant debris, weed seeds,
dirt, and other extraneous materials that favor seed deterioration. The seeds should
be examined for purity and variants should be removed. Seeds with mottling due to
SMV should be removed.
Testing for viability and longevity
A number of factors can influence seed quality and viability during production.
Poor seed with low viability will be even poorer after storage. Therefore, seed lots
need to be examined before storage. A good-looking seed may not necessarily be
good quality. Seed viability is usually measured when the seed is planted, but it is
also measured for industrial purposes (MacKay 1978). Incubator germination, field
emergence, tetrazolium, seedling growth rates, and seed leachates are some of the
tests used to evaluate seed viability (Kueneman 1982, MacKay 1978).
Genotypic differences in seed longevity have been reported (Kueneman 1983,
Paschal and Ellis 1978). Within a variety, a number of preharvest and postharvest
factors can influence seed longevity. These tests of seed longevity have been
proposed: seed storage (normal aging of seeds), accelerated aging stress, cold stress,
hot water pregermination stress, osmotic stress, thermo stress during germination,
and methanol stress (Kueneman 1982). Accelerated aging, pregerrnination, thermo,
and methanol stress are recommended for use in breeding for seed longevity.
Seed storage
Factors to consider in storing seeds until planting are initial seed moisture content,
genotype, temperature, RH, the container in which the seed is packed, and the
method of packing. At AVRDC, seeds are sun- or air-dried to 8% moisture content
for medium-term storage at 2-5 °C and 40-45% RH. Under these conditions,
soybean seed can be stored for 20 yr (AVRDC 1985, Cromarty et al 1982). With
8.1-9.4% seed moisture content, soybean seed can be stored at 10 ° C for 10 yr; at 13%

37 0 GREEN MANURE IN RICE FARMING
Table 4, Equilibrium moisture content of soybean at 25 0 C at 30-95% relative
humidity (RH) (Roberts and Roberts 1972).
Equilibrium moisture content at given RH
1 0% 30% 45%
60% 75%
95%
4.3 6,5 7.4 9.3 1 3.1 18.8
moisture content, it can be stored for 3 yr. At 20-30 °C, seed with 13-18% moisture
content will remain viable for less than a year (Toole and Toole 1946). Under
tropical conditions, high initial quality soybean seeds at 9-9.5% moisture content can
be safely stored 9 mo at 20-25 °C and 50-60% RH (Gregg 1982). Most AVRDC
breeding materials with good initial seed quality and 9-10% moisture content are
stored at 20-24 °C and 55-60% RH. The majority of the entries stored under these
conditions retained more than 80% viability for at least 2 yr. Similar storage
conditions are suitable for mungbean.
If storage conditions have a higher RH, there is no need to dry the seed to less
than equilibrium moisture content. At 45% RH or lower, seed should be dried to
7.4% moisture content or lower. At 60% RH, drying the seed to 9% moisture will
suffice. Soybean seed moisture content at 25 °C with different relative humidity
levels are given in Table 4.
The usual rule of thumb for storage conditions for the short term is percent RH
and degrees Fahrenheit totaling 100 or less (James 1961).
The viability of soybean is determined using an age index concept.
Age index (AI) = months in storage X Io'""( X 10
0.06451
Where MC = moisture content (%), T = temperature (°C), and months in storage =
Log AI-0.143M C-0.0645T.
Fungi activity during storage below 75% RH is very low; below 62% RH, all
storage fungi are completely inactive (Roberts 1972a). Below 60% RH, storage
insects are inactive. Because rnungbean weevil is a serious storage pest, it is
.important to maintain RH below 60% and seed moisture content below 8% (Roberts
1972a).
The minimum germination required for seed certification varies among
countries. For soybean, it is 80% in the US, but many seedmen demand 90%
(Tekrony et al 1978). In India, it is 70%. For mungbean, minimum germination in
India is 75% (Agrawal 1980).
Under ambient conditions, mungbean appears to be storable longer than
soybean (Table 5). Traditional mungbean varieties appear to have a high proportion
of hard seeds, but hard seededness decrease with age in storage. Mungbean seed
loses hard seededness with a year (Pathwardhan 1927).
During domestication, the hard seededness character was selected out. It
appears probable that this trait in mungbean can be used in breeding for good seed
quality (B. C. Irnrie, pers. comm.). Soon after harvest, hard-seeded rnungbean
germination is low, but it improves with storage (Rajasekara Mudaliar and

SEED PRODUCTION AND MANAGEMENT OF MUNGBEAN AND SOYBEAN 371
Table 5. Germination of quality seed tested after different durations in storage at ambient conditions
in Delhi, India (Agra al 1980).
Crop
Germination (%)
0 3 mo 6 mo 12 mo 18 mo 24 mo 36 mo 37 mo
Mungbean cultivar P. S.-16 . 99 99 99 99 98 98
Soybean cultivar Bragg 94 93 81 43 14 0 0 0
Table 6. Germination of soybean seed stored in different containers at amieient
room temperature and cold room for different durations in Sri Lanka
(Aruinandhy 1987).
Storage period
( mo.)
Storage condition
Gunny bag
Germination (%)
Polyethylene bag
0 Ambient 90 90
Cold 90 90
3 Ambient 80 81
Cold 88 80
6 Ambient- 2 70
Cold 79 81
Sundararaj 1954). Even after 1 1 yr of storage, hard-seeded mungbean had 70%
germination (Sonavene 1928). In soybean, a certain proportion of hard seeds in a
variety seems to improve seed longevity and germination (Potts et al 1978).
Because farmers in the tropics do not have sophisticated cold storage facilities,
practical storage methods need to be developed. Harrington (1963) suggested using
steel bins with steel lids, or steel drums with an aluminum foil layer and a gasket seal,
sealed tin cans, hermetically sealed glass jars, sealed aluminized polyester pouches,
or sealed high-density polyethylene bags. Metal drums with gasket seals are
common in Taiwan. Sealed polyethylene bags kept in a shaded area can safely store
seed for 6-9 mo (Table 6). Vaporproof packages for storage protect seed from drastic
fluctuations in RH. For a detailed review on this topic, see Delouche et al (1973),
Delouche (1975), and Nangju et al (1978).
Although storage facilities, low RH, and temperature are known to ward off
mungbean weevil, such facilities are unavailable in developing countries in the
tropics. Asian villagers traditionally have used peanut oil to protect pulse grains
against storage insects. Results at AVRDC suggest that peanut oil or soybean oil at
2-3 ml/ kg of seed can effectively suppress weevil reproduction in stored mungbean
for 3 mo (AVRDC 1976).
In India, treatment with neem oil, activated clay, and red earth is common.
Asian farmers also mix seeds with ash to prevent moisture buildup.
If the integrity of the seed is violated before or after harvest, then the seed is
vulnerable to damage by biotic factors. Almond moth Ephestia mute/1a can develop

37 2 GREEN MANURE IN RICE FARMING
on soybean in storage. An intact seed coat is an effective barrier to infestations.
Soybean saponin extracts have been found to inhibit development of mungbeari
.
weevil and soybean almond moth. The saponins or their glucosides seem to produce
typical antibiotic symptoms (Sirisingh and Kogan 1982).
Future of seed production
Rapid advances in innovative breeding concepts and procedures will surely modify
concepts of crop varieties in the future ( Jensen 1 965). In soybean, there are blends,
mixtures of two or more pure lines, multiline varieties, and short breeding cycle
varieties ( less uniform )
; there is a potential for hybrids and genetically engineered
varieties. Some of these will not conform to the variety norm of purity, homogeneity,
and distinctness. Seed production and certification of these new products will be a
challenge ( Jensen 1965, Lafever 1985). The products will have greater variability for
plant type. The working philosophy of the future will emphasize performance over
uniformity. In such cases, seed certification probably should monitor seed quality
rather than distinctness.
Diagnostic tests for germination should include rapid vigor tests, disease tests,
seed treatment tests, and variety identification tests (Voris 1985). A simple,
inexpensive, and practical way to efficiently produce, harvest, thresh, clean, and
store good quality seed for small farmers is needed. The mechanisms involved in
protecting against insects using home remedies such as peanut oil need further
exploration. Research also should focus on the reasons for good seed quality with
small seeds and black seeds, with or without hard seededness. The role of the
environment at different stages of seed development and its relevance to seed
deterioration deserve further study. Because farmers are interested in storing seed
at most for 6-9 coo, research with that objective should be distinguished from
commercial concerns for longer term storage.
There is growing awareness, even in developing countries, of the need to obtain
quality seed for planting. Farmers consider it an important single investment that is a
prerequisite-if all other management inputs are to pay off. But both government and
private industry are unable to meet the demand or provide good quality seed. The
price of certified seed is almost double the price of regular seed ( in Thailand, regular
seed costs US$1.40/kg; certified seed costs $3.0/k p )(Potao 1987). However, the
government offers subsidies or other means of obtaining quality seed. Governments
also should encourage the private seed industry to meet local demand without
unduly exploiting the farmers.

.
SEED PRODUCTION AND MANAGEMENT OF MUNGBEAN AND SOYBEAN 373
References cited
Agrawal P K ( 1980) Relative storability of seeds of ten species under ambient conditions. Seed Res.
X(2): g 440.
Aru|nundhy V (1987) Soybean research in Sri Lanka. In Soybean varietal improvement. S.
6hunmuguxondx,um ` P. Luxbmoxu.and N. Llemit, eds., Asian Vegetable Research and Development
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Notes
Address: S. Shanmugasundaram, Asian Vegetable Research and Development Center, P.O. Box 42,
Shanhua, Taionn74i gg , Taiwan, China.