Indian Journal of Entomology

Open Access
SCOPUSWeb of Science
  • Year: 2019
  • Volume: 81
  • Issue: 3

LC50 and relative toxicity of plant extracts against cowpea aphid Aphis craccivora koch

Department of Entomology, College of Agriculture, Assam Agricultural University, Jorhat

Abstract

A laboratory bioassay was carried out to determine the LC50 and relative toxicity of three botanicals (leaf extracts) along with a check imidacloprid 17.8 SL and control on the cowpea aphid Aphis craccivora Koch. Extract of Polygonum hydropiper showed the maximum efficacy (LC50-0.341%) followed by Murraya koenigii (0.707%) and Pongamia pinnata (3.357%) after 72 hr exposure. Considering the relative toxicity of imidacloprid as unit value, P. hydropiper, M. koenigii and P. pinnata were 0.090, 0.043 and 0.009x less toxic, respectively.

Keywords

Aphis craccivora, Polygonum hydropiper, Murraya koenigii, Pongamia pinnata, toxicity, leaf extracts, imidacloprid, LC50