The newly hatched larvae from the eggs of leaf eating caterpillar (Spodoptera), armyworms and hairy caterpillar remain on lower surface of the leaves and scrap the green matter.  Leaves become opaque.  Advance stages of caterpillars feed on leaves and make irregular holes on them.  On higher infestation, plants are defoliated totally.  The larvae of semi looper remain on leaves and damages the crop.  Raise castor plants around the field. The adults of leaf eating caterpillar prefer to lay eggs in masses on lower surface of the leaves. Collect & destroy such egg masses along with castor leaves.  The NPV (Nuclear Polyhedrosis Virus) of leaf eating caterpillar is now available, spray it @ 250 LE in 500 lit of water per hectare at evening time. Crop should be uniformly covered with spray fluid.  The farmers who grows crop organically should spray Bacillus thuringiensis, a bacterial base powder @ 15 g or Beauveria bassiana, a fungus base powder @ 40 g per 10 lit of water.  Spray neem seed kernel powder @ 500 g (5%) or neem base formulations @ 20 ml (1% EC) to 40 ml (0.15% EC) per 10 lit of water.  On higher infestation, spray chlorantraniliprole 18.5 SC @ 3 ml or profenophos 50 EC @ 10 ml or thiamethoxam 12.6% + lambda cyhalothrin 9.50% ZC @ 3 ml or indoxacarb 15.8 SC @ 10 ml or flubendiamide 20 WG @ 5 g or spinatoram 11.7 SC @ 10 ml or lambda cyhalothrin 4.90 CS @ 5 ml or DDVP 76 EC @ 10 ml per 10 lit of water.  At each spray, insecticides should be changed.