Life cycle and morphometric analysis of fall armyworm, Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) on Zea mays

Abstract

Research conducted under controlled laboratory conditions (at 25±5°C and 75% relative humidity) on fall armyworm (Spodoptera frugiperda, J. E. Smith) reared on a natural diet derived from maize crops revealed a life cycle comprising four distinct stages: egg, larva, pupa, and adult. A single female produced 1005.50±48.14 eggs throughout her entire life span. The incubation period was 2.80±0.44 days with 95.92±1.02% hatchability of eggs. The larval stage was completed by passing through six instars. The average larval periods for first, second, third, fourth, fifth and sixth instar larvae were 2.60±0.49, 2.70±0.46, 2.50±0.50, 3.10±0.83, 3.30±0.64 and 4.50±0.67 days, respectively. The total larval duration varied from 13 to 21 days, with a mean duration of 17.40±2.36 days. The average pupal period was 11.40±1.36 days. Female moths had a pre-oviposition period of 4.20±0.75 days that included a sexual maturity period. The oviposition and post-oviposition period recorded was 3.40±0.49 and 6.80±0.75 days, respectively. Longevity of males and females were recorded at 8.00±0.89 and 12.00±1.90 days, respectively. The mean total life cycle of males and females were observed to be 36.80±3.31 and 38.00±2.76 days with a range of 32-42 and 35-42 days, respectively.