Effect of green algal sea weed - Chaetomorpha antennina (Bory de Saint-Vincent) Kutzing’s acetone extract on the growth and development of tobacco caterpillar, Spodoptera litura (Noctuidae: Lepidoptera)

Abstract

Investigations on the green algal seaweed Chaetomorpha antennina (Bory de Saint-Vincent) Kutzing for their insecticidal and inhibition effect on Spodoptera litura Fabricius were conducted under laboratory conditions in Department of Entomology. Experimental results on the larvicidal action of acetone extract exhibited no effect up to 24 hours of treatment. C. antennina acetone extract @ 10 per cent concentration demonstrated the highest larval mortality in all the periods of observation and a gradual increase in mortality was observed up to 7th day (66.67%). Even though the larval mortality was gradual among the treatments, pupation was at variable level among the treatments and the pupal to adult conversion was comparatively lower in all the treatments. Adult emergence data exhibited pupal: adult conversion ratio of 1:0.54 C. antennina 10 per cent treatment whereas in control and solvent control the ratio was 1:0.92.