author(s)
Nila Win and Krishna Rolania

abstract
The life cycle of lesser grain borer, Rhyzopertha dominica, on wheat 1105 was studied for seasonal variation at room temperature during winter at 21±7 ºC in winter and at 28±5 ºC in rainy season. The result shows that more fecundity (306.8±16.36 eggs) was in rainy season as compare to winter (170.8±16.08 eggs). The incubation period was very similar in both seasons i.e. (11.5±3.44 days) in winter and (11.4±1.50 days) in the rainy season. The total larval and pupal period was (35.8± 2.78 days) and the developmental period was (47.2±3.01days) in rainy season as compare to longer (81.7±5.89 days) and (88.62± 2.98 days) in winter, respectively. The seasonal variations also have the impact on the longevity of male: female, which was longer (38.9±3.91: 41.7±3.49 days) in winter and shorter (28.9±2.68: 32.75±2.82 days) in rainy season. The sex ratio was 0.84: 1.04 in winter and 0.90: 1.10 in the rainy season. Higher mean growth index 2.01 was recorded in rainy season and lower growth index 1.02 was observed in winter.