In general organophosphates and carbamates pesticides are used at very high doses for pest managementas an effective strategy to protect food and other agricultural crops. Synthetic pesticides also pose serious threats to the environment and non-target organism. As an alternative safe strategy natural bio-pesticide based on phytochemicals as active ingredients obtained from plants hold a viable option and being popular due to their eco-friendly and non-toxic properties. Calotropis procerais a weed known for its high medicinal propertiesin Indian system of medicine for the treatment of various ailments. Its antioxidant and free radical scavenging activities followed by bio-efficacy of methanol, hexane and chloroform soluble extracts were studied to explore their potential for pest control in food crops and assure food safety. Total phenolic contents were ranging from 25.6 to 39.4 mg/g gallic acid equivalent (GAE), antioxidant 45.6 to 67.4% and free radical scavenging activity by using DPPH (1,1-diphenyl-2 picrylhydrazyl) varied from 35.8 to 39.6 %. The extract showed potential insecticidal efficacy against experimental pest at 16.7% at 0.007 % lowest dose and 63.3% at 0.5% highest dose. Further, hexane highest (66.7%) at 0.5% and chloroform fraction showed highest (66.7%) mortality at 0.5% dose. The LD₅₀ and LD₉₀ data obtained for crude extract 0.080 and 9.411 % at fiducial limits of 0.026 to 0.485 and 1.027 to 18.147 respectively. The methanol extracts of aerial parts and their fractions were also screened alone and in combination to assess their insecticidal properties. The combination (1:1) of Calotropisprocera and Lantana camara extracts showed synergistically enhanced (2.5 fold) activity. Application of plants in particular weeds as free radical scavenger and bio-control agent in the management of pest in food safety will be presented.

Devendra Kumar

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