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An experiment was carried out at the Entomology Laboratory, Horticultural College and Research Institute for Women, Trichy in November-December 2013 to study the biology and development of Sitophilus oryzae L. under laboratory conditions. Observations were made on oviposition rate, total number of eggs, adult emergence per 100 grains, egg to adult survival percentage, adult longevity, adult emergence period and reproductive potential. The oviposition rate per female (9.43 nos), total number of eggs (94.30 nos), adult emergence per 100 grains (38.50 nos), reproductive potential (35.50 nos), egg to adult survival percentage (41.85), adult female longevity (12.88 weeks) and adult male longevity (8.33 weeks) were higher in redgram under room temperature condition feeding by the respective population as compared to controlled condition. In case of sorghum, all the above parameters were superior to redgram feeding by the respective population under room and controlled temperature condition. The larval (26.13 days), pupal (7.63 days) and adult emergence period (33.75 days) was maximum in lentil under room temperature as compared to controlled condition. In case of sorghum, larval, pupal and adult emergence period was minimum when compared to split pulses feeding by the respective population irrespective of temperature and humidity.

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Rice weevil Sitophilus oryzae (L.) mainly attacks whole grains such as wheat, corn, barley and rice and have been found actively breeding in such foods. The host range of S. oryzae now extended to split pulses. An experiment was carried out at the Entomology Laboratory, TNAU, Coimbatore during 2014-2015 to study the comparative development of sorghum, redgram and rice breeding population of S. oryzae feeding on cereals and split redgram dhal. The assessed parameters were survival percentage, per cent mortality and F1 progeny. The per cent mortality was higher in sorghum breeding population while feeding on redgram (98.33%) and rice (44.67%). In case of redgram breeding population per cent mortality was maximum in rice (21.67%) and sorghum (19.67%). The survival percentage was maximum in sorghum population while feeding on sorghum (95 %). F1 progeny emergence of sorghum breeding population was higher while feeding on sorghum (75.67%) and rice (36.67%). In case redgram breeding population F1 progeny emergence was maximum in redgram (62.33%) and sorghum (15.33%), whereas in rice breeding population maximum progeny emergence was observed in rice (72.33%) and sorghum (65.67%). The cereal bred population did not survive on redgram, whereas redgram bred population able to survive on cereals, but the progeny emergence and their development was affected.