EXPLORING THE EFFICACY OF CNSL-BASED BOTANICAL PESTICIDES FOR THE MANAGEMENT OF PESTS OF BHINDI (ABELMOSCHUS ESCULENTUS)

Abstract

The consistent use of chemical pesticides over the years has led to various issues. To mitigate these problems, botanical insecticides have been used as a better alternative. One such botanical insecticide is cashew nut shell liquid (CNSL 20% EC), which contains a mixture of phenolic compounds. Under laboratory conditions, this insecticide was assessed against Sylepta derogata larvae in different concentrations ranging from 0.1 to 1, along with a chemical control. At 5, 7, and 10 DAT, CNSL 1% was found to be the most effective treatment, with 90% mortality recorded. A probit analysis was conducted to determine the effective dose, which was found to be 1%. The CNSL 20% EC was modified to produce two combination products, EC1 and EC2, by substituting half of the active ingredient with neem oil and pongam oil respectively, without changing other ingredients and their proportion. The developed formulations were evaluated for product stability and emulsion properties. A pot culture experiment was conducted on bhindi crops once during the vegetative and reproductive phases. At 7 DAT, EC1 @ 1% and CNSL 20% EC @ 1% caused over 95% reduction of sucking pests such as Amrasca biguttula biguttula and Aphis gossypi compared to the control. However, CNSL 20% EC produced only a 76.48% reduction of the chewing pest S. derogata, whereas treatments with EC1 and EC2 showed over 80% reduction. Sucking pests were effectively reduced (by more than 90%) by the application of EC2 as well. It was concluded that the combination products EC1 and EC2 were more effective in controlling pests than CNSL alone.