Effects of Food on the Longevity, Fecundity, and Development of Adult Coccinellids (Coleoptera: Coccinellidae)

Abstract

AbstractAccess to drinking water increased the longevity of Coccinella trifasciata perplexa Muls. by about 35%. The water content of field-collected insects was 70% and of laboratory-fed insects 64%. Rate of loss of water increased, and longevity decreased when protein was absent from the food.Anatis mali Auct. lived more than 1000 days and Coleomegilla maculata lengi Timberlake lived more than 400 days when fed on various synthetic foods. Seven of 13 species tested kid eggs when fed on these foods. A diet containing desiccated liver was the best non-prey food supplement for reproduction, and adults of three generations of C. maculata were kept on this food.A. mali preferred dry powdered pea aphids, Acyrthosiphon pisum (Harr.), to either bean aphids. Aphis fabae Scop., or corn aphids, Rhopalosiphum maidis (Fitch), whereas C. maculata preferred corn pollen to aphids and A. pisum and R. maidis to A. fabae. Previous feeding did not affect the preference of either A. mali or C. maculata for dry aphids or pollen. C. maculata produced six eggs per mg. of food while feeding on A. pisum and four on R. maidis. Young adults ate more than older adults.The rate of food intake was highest in A. mali during the first two weeks and in C. maculata during the first eight days after emergence. The living weight and dry weight of feeding C. maculata adults increased for eight days and then did not vary, whereas the water content decreased in this period. The index of relative growth was about 0.10 mg. per day per mg. of adult weight and food efficiency was about 0.18 mg. per mg. of food.