Developmental effect of cashew nut shell extract against nymphal instar of Silver leaf Whitefly (Bemisia tabaci Genn.)

Abstract

Cashew nut shell (CNS), which are one of the most still is tropical biomass waste. This study was aimed to test mortality rates of CNS extract against the first to third instar nymphs of Silverleaf Whitefly (Bemisia tabaci Genn.1889). The concentration of CNS extract were: 0.22 %, 0.67 %, 2.00 %, 6.00 %. The LC50 and LC90 values indicated that CNS extract at concentration of 2.00 % were the most toxic compound to the first instar stage followed by CNS extract at concentration of 6.00 %, 0.67 %, imidacloprit, and CNS at concentration of 0.22 %, respectively. The concentration of 6.00 % showed the most toxic effect to the second stage followed by CNS extract at concentration of 2.00 %, 0.67 %, imidacloprit, and CNS at concentration of 0.22 %, respectively. The lethal concentration (LC50−90) value of the CNS extract at concentration of 6.00 %, at concentration of 2.00 %, 0.67 %, imidacloprit, CNS extract at concentration of showed the toxicity against the third instar nymph. This CNS extract at concentration of 2.00 % could be used to suppress of the B. tabaci nymphs of different stages (first to third instar) and negative effect of phytotoxicity on the soybean leaves.