Feeding Deterrence, Acute Toxicity and Sublethal Growth Effects of Kojic Acid Isolated from Aspergillus funiculosus

Abstract

Aspergillus funiculosus NCIM 1029 has been reported for the production of kojic acid exhibiting antibacterial, antifungal and larvicidal activity against 3rd instar larvae of Aedes aegypti. Aim of the Study: To check the antifeedant, acute toxicity and sublethal growth effects of fungal metabolite, kojic acid against the agriculture pest, Spodoptera litura. Materials and Methods: Kojic acid was checked for feeding deterrence activity against 4th instar larvae of S. litura in comparison to insect antifeedant, azadirachtin. Reduction in the weight and length of the larvae was evaluated after three days of exposure to kojic acid (400μg/ml). The effect of kojic acid on pupation and adult emergence was also studied. Results: On determination of feeding deterrence, the DC50 value for kojic acid was found to be 180.645 ± 6.35μg/ml on comparison to azadirachtin (DC50 = 41.372 ± 2.21). The LD50 & LD90 values of kojic acid were found to be 693.52± 51.31 and 1889.13 ± 279.03μg/ml, respectively. The reduction in larval weight and length were 83.24 and 87.50%, respectively. The percentage pupation and adult emergence were reduced by 69% and 64% for the exposed larvae. Conclusions: Kojic acid showed moderate feeding deterrence, acute toxicity and sublethal growth effects against S. litura. Keywords: Aspergillus funiculosus, kojic acid, Spodoptera litura, acute toxicity, antifeedant.