Feeding assimilation of fall armyworm (Spodoptera frugiperda J.E Smith) (Lepidoptera: Noctuidae) larvae on several host types

Abstract

Spodoptera frugiperda (Noctuidae: Lepidoptera) is a pest that is easy to adapt and quickly develops. S. frugiperda can switch to crops other than maize as the primary host. Food assimilation must be tested to determine which plants S . frugiperda larvae prefer. This research was conducted to determine the feeding assimilation of S. frugiperda larvae and determine plants that can be alternative hostsinstead of maize . This study was arranged using a completely randomized design (CRD) with three treatments and five replications to obtain 15 experimental units. Larvae feed consists of rice, maize, and Napier grass. Feed is given during their 3rd instar stage until it becomes a prepupa. The suitability of plants as a food source for insects can be determined by a food assimilation test calculated using the Gravimetric method. The findings from the observations of food assimilation of S. frugiperda larvae in larvae-fed maize had higher consumption rate, growth rate, and digestibility than larvae-fed Napier grass. The conversion efficiency of digested food in grass-consuming larvae is 24.173%, higher than maize, 10.227%, and rice 0.00%. In compliance, the efficiency of food utilization was higher for larvae-fed Napier grass compared to those fed maize and rice.