Biology of eri silkworm, Samia ricini (Donovan) on castor, Ricinus communis L.

Abstract

Studies on biology of eri silkworm, Samia ricini (Donovan) on castor, Ricinus communis under laboratory condition revealed that the eggs were laid in clusters on kharika. A female laid average 360.10±23.88 eggs with 97.17±2.09 per cent hatching and 8.83±0.91 days of incubation period. The duration of first, second, third, fourth and fifth instar larva were 3.77±0.43, 3.23±0.43, 3.70±0.47, 4.60±0.50 and 7.67±0.55 days, respectively with total larval duration of 22.97±0.85 days. The prepupal and pupal periods were2.63±0.49 and 15.73±0.74 days, respectively. The pre-oviposition, oviposition and post-oviposition period were 11.61±0.37, 70.47±1.78 and 122.73±4.81hrs, respectively. The female and male longevity were 204.82±5.24and155.99±7.99hrs, respectively with sex ratio of 1:2.01 (Male: Female).