**1.6 Cultivation in India**

200 Agricultural Science

Green gram is a warm-season crop and grows mainly within a mean temperature range of 20–40°C, the optimum being 28–30°C; hence, can be grown in summer and monsoon season/autumn in warm temperate and subtropical regions and at altitudes below 2000 m in the tropics. It is sensitive to frost. It is mostly grown in regions with an average annual rainfall of 600–1000 mm, but it can do with less. It withstands drought well, by curtailing the period of flowering and maturation, but it is susceptible to water-logging. High humidity at maturity causes damage to seeds leading to seed discoloration or sprouting while still in the field. Green gram cultivars differ markedly in photoperiod sensitivity, but most genotypes show quantitative short-day responses, flower initiation being delayed by photoperiods longer than 12–13 hours. The crop grows well in a wide range of soil types, but prefers welldrained loams or sandy loams with pH (5–) 5.5–7 (–8). Some cultivars are tolerant to

Green gram is propagated by seed. There is no seed dormancy, but germination can be affected by a hard seed coat. Green gram seeds are broadcast or dibbled in hills or in rows. Recommended sowing rates are 5–30 kg/ha for sole crops, and 3–4 kg/ha under intercropping. Recommended spacing ranges within 25–100 cm × 5–30 cm; whereas, for the more modern cultivars ripening in 60–75 days, maximum yields are obtained at plant densities of 300,000–400,000 plants/ha. The later-maturing traditional cultivars generally need wider spacing. Recommended spacing for sole crop of green gram in Kenya are 45 cm between rows and 15 cm within the row, with a seed rate of 6–10 kg/ha and a sowing depth of 4–5 cm. Mung bean can be grown mixed with other crops such as sugar cane, maize, sorghum or tree crops in agroforestry systems. Short-duration mung bean is often relay-cropped to make use of a short cropping period. In Kenya mung bean is usually intercropped with maize, sorghum or millet; it is occasionally grown in pure stands or intercropped with other pulses. The usual practice here is to place 1–2 rows of mung bean between rows of a cereal, or to plant mung bean in the cereal row. In pure stands, 1–2 weedings are necessary during the early stages of growth. In Kenya weeding is done using hoes and machetes. Farmers do not normally apply any inorganic fertilizer to a mung bean crop. Mung bean uses residues from fertilizer applications to the main crops in the system, though it responds well to phosphorus. Nutrient removal per ton of seed harvested (dry weight) is 40–42 kg N, 3–5 kg P, 12–14 kg K, 1–1.5 kg Ca, 1.5–2 kg S and 1.5–2 kg Mg. The nutrient removal is much higher when crop residues are removed to be used for fodder. In its major area of cultivation, the monsoon tropics, mung bean is mainly grown as a rainy season crop on dryland or as a dry-season crop after the monsoon in rice-based systems on wetland, making use of residual moisture or

**1.5 Cultivation in Kenya** 

moderate alkaline and saline soils (Mogotsi, 2006).
