The potential for controlling Megalurothrips sjostedti (Thysanoptera: Thripidae) on cowpea, Vigna unguiculata (L.) Walp flowers using extracts of cashew (Anacardium occidentale L.) products

Abstract

The efficacy of aqueous extracts of cashew, Anacardium occidentale L. products was tested on Legume flower bud thrips on field cowpea in the 1999 and 2000 seasons using nutseed and nutshell at 10% w/v, bark and leaf at 20% w/v. Aqueous extract of cashew nutshell was superior to other cashew products in reducing thrip populations in cowpea flowers and compared favourably with cypermethrin + dimethoate. Pod density per plant was significantly enhanced on cowpea plants sprayed with aqueous extract of cashew nutshell compared to other extracts. Cashew extract contains cardole (a caustic substance) and anacardic acid, which may have been responsible for its insecticidal effect on thrips. This result indicates the potential of cashew products especially the nutshell for integrated management of thrips in legume crops.

Keywords:

• Megalurothrips sjostedti
• cashew extract
• cowpea flowers
• integrated management

Acknowledgement

The authors are grateful to Mr Gideon Gbilin for his technical assistance and to the Director, Institute for Agricultural Research, Ahmadu Bello University for his kind permission to publish this report.