Effect of a seasonal changes on the life span of Bombyx mori L.

Effect of seasonal changes on the life cycle of multivoltine KA × NB hybrid of Bombyx mori was studied. The insects were fed on different varieties of mulberry leaves but kanva-2 variety of Morus indica was best amongst all. In rainy season, B. mori male had a life span of 44.35 days while female of 45.95 days. In winter life span for male was 59.80 days and for female 60.75 days. The life span in summer was 46.48 and 47.70 days for male and female, respectively. Seasonal differences in the life span of B.mori indicated that moderate upper and lower limits of temperature, higher relative humidity, greater number of cloudy days and total rain fall were more optimal for tissue growth and egg production.