Combining bio-pesticides with chemical pesticides to manage legume pod borer (Maruca vitrata) on yard-long bean in Thailand

Abstract

This study aims to confirm the potential of bio-pesticide application under field conditions in combination with chemical pesticides against the pest moth Maruca vitrata on yard-long bean. Four field trials were conducted at two locations (AVRDC East and Southeast Asia Regional Research and Training Station, and farmers’ fields in Kamphaeng Saen, Thailand) from March to May 2012 and May to August 2012. The yard-long bean pod damage by M. vitrata was significantly reduced by 23–85%, with substantial yield increases (22–190%) in Bacillus thuringiensis-based treatments in combination with cypermethrin, when compared with the untreated check. Although the combined effect of cypermethrin with Beauveria bassiana or neem-based treatments was better than the untreated check, the pod damage was still higher in these treatments, recording up to 26.87% compared with B. thuringiensis subsp. aizawai-treated plots. Based on these results, B. thuringiensis is a promising component for integrated pest management strategies against M. vitrata on yard-long bean in Thailand.

Keywords:

• Bacillus thuringiensis
• Beauveria bassiana
• Maruca vitrata
• neem
• yard-long bean

Acknowledgements

This study was supported with funds from the Federal Ministry for Economic Cooperation and Development, Germany.