Three green seaweed extracts and their fractions for ecofriendly management of pestiferous insect Spodoptera litura

Abstract

Polyphagous pest Spodoptera litura poses a serious threat to important agriculture crops and their products.A green ecofriendly alternative to existing chemical pesticides, bio-fertilizers are preferred to protect the crop and increase their yield against pests.Hence, three common seaweed crude extracts (Caulerpa scalpelliformis, Caulerpa veravalensis, and Ulva lactuca) and chromatographic fractions of C.scalpelliformis [CS-1 (683-759) and CS-2 (1038-1130)] were screened against S.litura under different concentrations in castor leaves.Dose-dependent mortality was observed for crude extracts and their column chromatographic fractions.Conversely, fractions [CS-1 (683-759) and CS-2 (1038-1130)] recorded highest mortality at 1.0 ppm and lowest at 0.12 ppm.GC-MS analysis of C.scalpelliformis and C.veravalensis exhibited the highest peak of n-Hexadecanoic acid and 1,4-Bis(trimethylsilyl) benzene, respectively.The access proportion index suggested C.scalpelliformis was more active than other seaweeds.Henceforth, the results suggest that the above seaweed extracts may be developed as bio-alternative agrochemicals for pest control