Life History of Common Cutworm, Spodoptera Litura Fabricius (Moctuidae: Lepidoptera) in Benguet

Abstract

Common cutworm, Spodoptera litura Fabricius underwent the holometabolous type of development. The insect duration of development is: egg (5.0 + 0.00 days), larva (23.9 + 0.71 days), pupa (17.80 + 2.33 days),
adult female (12.10 + 2.65 days) and male (7.45 + 1.31 days). The egg is round and dirty white. The body of the newly emerged larva is cylindrical; the size of the head is wider than the body while the abdomen is tapering to-wards the caudal region. But during the 2nd instar until pupation, the body turns wider than the head. The true legs and pro legs are distinct. The newly emerged larva is whitish, yellow green an hour after with a pattern of red, yellow, and green lines from the head to the anal region. As the larva grew bigger, the body turns brown with 3 thin yellow lines down the back. The newly emerged larva singled out the leaf veins during feeding while the big larva includes them. Bigger larva is an excellent feeder and active at night. The larva hides in the soil at day time and ceaseless when about to molt. The body length and width of the smallest and full grown larva, respectively are: 2.16 + 0.14 mm and 0.32 + 0.02 mm; 46.91 + 2.25 mm and 6.87 + 0.16 mm.

Pupation was in the soil. The pupa is elongated oval and shiny red. The body length and width measures 22.29 + 0.71 mm and 7.51 + 0.36 mm, respectively. The adult female and male are hairy. The female is pale
brown while the male is darker. The female is bigger with a stout abdomen while the male is narrower and tapering towards the tip. Courting the female lasted for 10 to 20 minutes while mating was 2-3 hours at between 2:00AM to 5:00AM. The eggs are laid in mass of 2-3 layers on the lower surface of the leaves near the petiole. Egg mass of 8.7 are laid within 12 days egg laying as the shortest and 14 days as the longest. There are 874.9 individual eggs in one egg mass.