Some aspects of the biology of the yam moth, Euzopherodes vapidella Mann (Lepidoptera: Pyralidae), a pest of stored yam tubers in Nigeria

摘要

Studies on the yam moth, Euzopherodes vapidella Mann (Lepidoptera: Pyralidae) showed that the mean fecundity per female was 79.0+1.7 eggs with an average oviposition period of 2.2 days. The eggs measuring 0.48±0.02mm in length and 0.28±0.03mm in width were laid singly, in chains and in batches. The percentage hatchability was 75. The duration of development for the different stages of E. vapidella was 3.5±0.5 days for egg, 14.5±0.8 days for the total larval stage, 1.5±0.8 days for the pre pupa and 7.5±0.5 days for the pupa stage. Total duration of development from egg to adult was 27.0±1.5 days. Unmated females lived longer (6.5 days) than unmated males (5.0 days), mated females (5.0 days) and mated males (3.0 days). The adult females were always bigger than the males. The wing span of the females ranged from 13.8-16.8mm and in males from 11.0-13.8mm. The body length for females ranged from 7.0-9.0mm and was 6.2-7.5mm for males. Relative humidity of 37% and below did not favour E. vapidelladevelopment with no adult emergence while 58% r.h and above favour development of the moth with significant adult emergence.