Department of Entomology, College of Agriculture, Andhra Pradesh Agricultural University, Rajendranagar, Hyderabad-500 030, Andhra Pradesh (India).
The effect of ambient temperatures on the developmental duration of Scymnus coccivora Aiyar was quantified by deriving regression equation for each developmental stage as well as the total life cycle. The duration of life stages was shorter during summer (15.65 days in April) and longer during winter (26.52 days in December). The male to female ratio of beetle population was 1:0.95. Each female S. coccivora laid 84.7 eggs on an average when reared on grape mealybug, Maconellicoccus hirsutus Green. The percentage hatchability of the eggs was 89.86. The longevity of male and female beetles, respectively was 61.7 and 66.8 days when fed on grape mealybug. The adults were the potential feeders of mealybug eggs when compared with the grubs. Adult consumed 864.4 eggs, whereas larval consumption was 314.2 eggs during the life time. Preference for feeding was evident with M. hirsutus followed by Ferrisia virgata and Plunococcus spp.
