**1.1 Importance of the crop and its cultivation**

Pulses, the food legumes, have been grown by farmers since millennia providing nutritionally balanced food to the people of India (Nene, 2006) and many other countries in the world. The major pulse crops that have been domesticated and are under cultivation include black gram, chickpea, cowpea, faba bean, grass pea, green gram, horse gram, lablab bean, lentil, moth bean, pea and pigeon pea. The probable geographical origin of the more common pulses has been reported as:


Source: Nene, 2006

A low input, short duration, high value crop, mung bean fits very well into rice-wheat cropping systems and other crop rotations. It fixes nitrogen in the soil, requires less irrigation than many crops to produce a good yield, and helps maintain soil fertility and texture. Including green gram to the cereal cropping system has the potential to increase farm income, improve human health and soil productivity, save irrigation water and promote long term sustainability of agriculture (Chadda, 2010).

#### **1.2 The plant**

Insect Pests of Green Gram *Vigna radiata* (L.) Wilczek and Their Management 199

the soap industry. Sprouted mung bean seeds are eaten raw or cooked as a vegetable; in French they are erroneously called '*germes de soja*', in English 'bean sprouts'. Immature pods and young leaves are eaten as a vegetable. Plant residues and cracked or weathered seeds are fed to livestock. Mung bean is sometimes grown for fodder, green manure or as a cover crop. The seeds are said to be a traditional source of cures for paralysis, rheumatism,

Green gram is an important source of easily digestible high quality protein for vegetarians and sick persons. It contains 24 per cent protein, 0.326 per cent phosphorus, 0.0073 per cent iron, 0.00039 per cent carotene, 0.0021 per cent of niacin and energy 334 cal/100g of green gram. The gap between realizable and actual yields needs to be bridged up with appropriate technologies. The latter basically revolves around two aspects: production and protection. Although the former has been a subject of greater emphasis at all levels of strategy, yet the latter continues to suffer from neglect and a sort of apathy under the cover of ignorance, economic status of the farmers and many more factors. In India, Acharya (1985) has pointed out that plant protection remains a most neglected aspect in pulse cultivation; further stating that only 5 to 6 per cent of the growers use plant protection measures in only 1.5 per cent of the total area under this crop. In view of the above facts, for the control of various pests in green gram, only certain insecticides have

The composition of mature mung bean seeds per 100 g edible portion is: water 9.1 g, energy 1453 kJ (347 kcal), protein 23.9 g, fat 1.2 g, carbohydrate 62.6 g, dietary fibre 16.3 g, Ca 132 mg, Mg 189 mg, P 367 mg, Fe 6.7 mg, Zn 2.7 mg, vitamin A 114 IU, thiamin 0.62 mg, riboflavin 0.23 mg, niacin 2.3 mg, vitamin B6 0.38 mg, folate 625 μg and ascorbic acid 4.8 mg. The essential amino-acid composition per 100 g edible portion is: tryptophan 260 mg, lysine 1664 mg, methionine 286 mg, phenylalanine 1443 mg, threonine 782 mg, valine 1237 mg, leucine 1847 mg and isoleucine 1008 mg. The starch consists of 28.8per cent amylose and 71.2per cent amylopectin. Mung bean seed is highly digestible and low in antinutritional factors. It causes less flatulence than the seed of most other pulses, making it suitable for children and older people. Mung bean starch is considered to have a low glycaemic index, i.e. to raise the blood sugar level slowly and steadily. The composition of sprouted mung bean seeds per 100 g edible portion is: water 90.4 g, energy 126 kJ (30 kcal), protein 3.0 g, fat 0.2 g, carbohydrate 5.9 g, dietary fibre 1.8 g, Ca 13 mg, Mg 21 mg, P 54 mg, Fe 0.9 mg, Zn 0.4 mg, vitamin A 21 IU, thiamin 0.08 mg, riboflavin 0.12 mg, niacin 0.75 mg, vitamin B6 0.09 mg, folate 61 μg and ascorbic acid 13.2 mg. The essential amino-acid composition per 100 g edible portion is: tryptophan 37 mg, lysine 166 mg, methionine 34 mg, phenylalanine 117 mg, threonine 78 mg, valine 130 mg, leucine 175 mg and isoleucine 132 mg. Sprouting especially leads to an increased ascorbic acid concentration. Mung bean hay contains: moisture 9.7 per cent, crude protein 9.8 per cent, fat 2.2 per cent, crude fibre 24.0 per cent, ash 7.7 per cent, N-free extract 46.6 per cent, digestible crude protein 7.4 per cent, total digestible nutrients 49.3per cent. Aqueous extracts of mung bean seeds have shown in-vivo hypotensive and hepatoprotective effects in rats. Extracts from mung bean seeds and husks

coughs, fevers and liver ailments (Mogotsi, 2006).

been recommended by several workers.

have shown antioxidative effects.

The chemical composition of green gram (dal) has been worked out as:

**1.4 Nutritional facts** 

*Vigna radiata* (L.) Wilczek [Synonyms: *Phaseolus radiatus* L. (1753), *Phaseolus aureus* Roxb. (1832)], often known as green gram/mung bean, is native to India and Central Asia. It has been grown in these regions since prehistoric times (Vavilov, 1926) and as an important legume crop in India throughout the year. The Sanskrit name for green gram is *mudgaparni* or *mashaparni* as per ancient Indian literature the *Yajurveda* (c. 7000 BC). While green gram cultivation spread over to many countries, especially in tropical and subtropical Asia, black gram (*Vigna mungo*) cultivation has remained more or less confined to South Asia. The progenitor of these pulses is believed to be *Vigna trilobata*, which grows wild in India (Nene, 2006). The more common vernacular names include: mung bean, green gram, golden gram (En). Haricot mungo, mungo, ambérique, haricot doré (Fr). Feijão mungo verde (Po). Mchooko, mchoroko (Sw) (Mogotsi, 2006).

The genus *Vigna* comprises about 80 species and occurs throughout the tropics. *Vigna radiata* belongs to the subgenus *Ceratotropis*, a relatively homogenous and morphologically and taxonomically distinct group, primarily of Asian distribution. Other cultivated Asiatic *Vigna* species in this subgenus include *Vigna aconitifolia* (Jacq.) Maréchal (moth bean), *Vigna angularis* (Willd.) Ohwi & Ohashi (adzuki bean), *Vigna mungo* (L.) Hepper (black gram or urd bean), *Vigna trilobata* (L.) Verdc. (pillipesara) and *Vigna umbellata* (Thunb.) Ohwi & Ohashi (rice bean). Hybrids have been obtained between many of these species. The species have often been confounded, especially *Vigna radiata* and *Vigna mungo*. The wild types of mung bean, which are usually smaller in all parts than cultivated types, are usually classified into 2 botanical varieties: – var. *sublobata* (Roxb.) Verdc., occurring in India, Sri Lanka, South-East Asia, northern Australia (Queensland), in tropical Africa from Ghana to East Africa, southern Africa and Madagascar; – var. *setulosa* (Dalzell) Ohwi & Ohashi, with large, almost orbicular stipules and dense long hairs on the stem, and occurring in India, China, Japan and Indonesia. The cultivated types of mung bean are grouped as *Vigna radiata* var. *radiata*, although a classification into cultivar groups would be more appropriate. Two types of mung bean cultivars are usually distinguished, based mainly on seed colour: – golden gram, with yellow seeds, low seed yield and pods shattering at maturity; often grown for forage or green manure; – green gram, with bright green seeds, more prolific, ripening more uniformly, less tendency for pods to shatter. Two additional types are recognized in India, one with black seeds and one with brown seeds (Mogotsi, 2006).

#### **1.3 Uses**

Mature mung bean seeds or flour enter a variety of dishes such as soups, porridge, snacks, bread, noodles and even ice-cream. In Kenya mung bean is most commonly consumed as whole seeds boiled with cereals such as maize or sorghum. Boiled whole seeds are also fried with meat or vegetables and eaten as a relish with thick maize porridge ('ugali') and pancakes ('chapatti'), whereas consumption of split seeds (dhal) is common among people of Asian descent. In Ethiopia the seeds are used in sauces. In Malawi the seeds are cooked as a side dish, mostly after removing the seed coat by grinding. In India and Pakistan the dried seeds are consumed whole or after splitting into dhal. Split seeds are eaten fried and salted as a snack. The seeds may also be parched and ground into flour after removing the seed coat; the flour is used in various Indian and Chinese dishes. The flour may be further processed into highly valued starch noodles, bread, biscuits, vegetable cheese and extract for the soap industry. Sprouted mung bean seeds are eaten raw or cooked as a vegetable; in French they are erroneously called '*germes de soja*', in English 'bean sprouts'. Immature pods and young leaves are eaten as a vegetable. Plant residues and cracked or weathered seeds are fed to livestock. Mung bean is sometimes grown for fodder, green manure or as a cover crop. The seeds are said to be a traditional source of cures for paralysis, rheumatism, coughs, fevers and liver ailments (Mogotsi, 2006).
