Assessment of the Influence of Artificial Dietary Supplements on Aspects of Biology of Adult Cocoa Moth, Ephestia Cautella

Abstract

Access of adult insects to food supplement will affect the intrinsic life history traits. Artificial diets are important for mass culture of insects for research and other purposes. Therefore, the effects of sugar diet on the aspect of longevity of adults, fecundity of female and hatchability of eggs of cocoa moth, Ephestia cautella W. (Lepidoptera: Pyralidae) were investigated in the laboratory at ambient temperature 27 ± 2oC, 70± 5% relative humidity and 12:12 hour photoperiod). Prior to mating, homogenous cultures of E. cautella reared on cocoa powder artificial diet were exposed to: water without sugar (WWS), sugar solution at 5% –Sa, sugar sugar at 10% –Sb and no water, no sugar (NSNW)control. The result showed a significant increase (P > 0.05) in the pre-oviposition period of Sa (3.17±1.80) > Sb (2.42±1.18) > WWS (2.08±0.79) > NSNW (1.75±0.75). The incubation period was 4.7days, 4.0 days and 4.6 days and 3.2 days in NWNS, WWS, Sa and Sb respectively. Fecundity ranged between 21.95 ± 7.82 in mated male X mated female to 131.05 ± 31.73 in virgin female treated to 10% sugar solution X virgin male without treatment. Female longevity significantly reduced in virgin female with 10% sugar solution (3.30 ± 0.24 days) than in virgin female without treatments (7.40 ± 0.17 days) and mated female treated to 5% sugar solution (7.40 ± 0.21 days). However, there was no significant difference (P > 0.05) in the longevity of virgin male without treatments (9.75 ± 0.23 days), mated male without treatments (9.00 ± 0.10 days) and virgin males treated to 5% sugar solution (9.45 ± 0.71 days). Diets and other supplements can be modified so as to suppress and/or improve the intrinsic life history traits in insects, which can be harnessed in mass rearing of insects, as well as a nonchemical technique in pest management.