Biology and degree day estimation of African bollworm Helicoverpa armigera (Hubner) on chickpea crop in Eritrea

Biology and degree days of African bollworm, Helicoverpa armigera (Lepidoptera:Noctuidae) studied at Hamelmalo Agricultural College, Eritrea, located in east Africa revealed that the bollworm adult female during its oviposional period of 3 to 4 days could lay as many as 300–350 eggs is its life span. It was also observed that the pest passing through its different life stapes viz., egg, larval (six instars), pre-pupal and pupal (lasting for 3.5, 25, 1.5 and 12 days, respectively) took an average of 42.0 days with 396.67 degree days to develop. The longevity of males and female was observed to be of 11 and 13 days, respectively.