· Gram · Cotton · Soybean · Peanut
Freshly hatched larvae feed gregariously on leaves, scraping the leaf tissue and completely stripping the plant. Older larvae disperse and feed voraciously on foliage at night. During the day, they usually hide in the soil around the base of the plants. In lighter soils, the larvae can reach the groundnut pods and damage them. Due to extensive feeding, only petioles and branches are left behind. Larvae and adults thrive at temperatures between 15 and 35°C . However, they favor higher temperatures within this range.
Adult moths have greyish brown bodies and variegated forewings with white wavy markings on the edges. The hindwings are translucent white with brown lines along the margins and the veins. Females lay hundred of eggs in clusters on the upper leaf blades, covered with golden brown scales. After hatching, the hairless light-green larvae disperse quickly and start feeding gregariously on leaves. Older larvae are dark green to brown with dark spots on the flanks and somewhat clearer bellies. Two yellow longitudinal bands run along the sides, interrupted by black triangular spots. An orange band runs dorsally between these spots. Larvae feed during the night and take refuge in the soil during the day.
Parasitoid wasps of the species Trichogramma chilonis, Telenomus remus or Apanteles africanus feed on eggs or larvae. Bioinsecticides based on Nuclear Polyhedrosis Virus (NPV) or Bacillus thuringiensis also work fine. Alternatively, the insect pathogenic fungi Nomuraea rileyi and Serratia marcescens can be sprayed on leaves. Bait solutions based on rice bran, molasses or brown sugar can be distributed on the soil in the evening hours. Plant oil extracts of neem leaves or kernels and extracts of Pongamia glabra seeds are highly effective against Spodoptera litura larvae on groundnut leaves.
Always consider an integrated approach with preventive measures together with biological treatment if available. Extensive insecticide use can lead to resistance in the pest. Azadirachtin, imidacloprid or Quinalphos can be used during the egg stage and prevents the larvae from hatching. To control the young larvae carbaryl, quinalphos, dichlorvos or diflubenzuron could be used. Baits solution based on carbaryl also effectively reduces populations.