Synthesis of colloidal chitosan from sea waste and its antifeedant effect against maize fall armyworm Spodoptera frugiperda (J.E. Smith)

Abstract

Fall armyworm (FAW), Spodoptera frugiperda (J.E. Smith) is one of the most important pests of maize, suddenly appeared in India 2018 and other cereal crops. The colloidal chitosan was synthesized in the laboratory, from the waste of sea food and studied for its bio efficacy by leaf dip bioassay on FAW. The antifeedant effect was assessed on first instar larva at concentration of one, three, five and seven per cent under no choice condition. The one and 7 per cent colloidal chitosan showed 40.51 per cent and 85.38 per cent antifeedant effect over untreated check respectively. The leaf weight loss was observed at one and 7 per cent colloidal chitosan exhibited 24.95 and 11.05 per cent respectively. The per cent reduction in leaf consumption on weight basis was 66.68 per cent when fed with 7 per cent colloidal chitosan treated leaf. Among different concentration used 7 per cent colloidal chitosan showed higher antifeedant effect against first instar larva of FAW.