author(s)
Robiah Noor Ahmed, Mohammad Mahir Uddin, Md. Azizul Haque and Kazi Shahanara Ahmed

abstract
Globally, legume pod borer, Maruca vitrata F. is one of the major constraints in increasing the production of grain legumes including Yard-long bean (Vigna unguiculata subspecies sesquipedalis). The present research was conducted to evaluate the efficacy of two microbial derivatives viz. emamectin benzoate and spinosad along with a widely used chemical insecticide Nitro 505 EC for the management of legume pod borer M. vitrata in the field laboratory of the Department of Entomology, Bangladesh Agricultural University, Mymensingh during kharif season 2016. The experiment was done following RCBD with three replications of each treatment along with an untreated control. Microbial derivative, emamectin benzoate @ 1.0 g/L showed a significant better performance in comparison to spinosad and widely used chemical insecticide Nitro 505 EC in respect of benefit cost ratio and bio-efficacy on M. vitrata which reduced 55.52 and 68.37% flower and pod infestation, respectively subsequently resulting 47.90% increasing pod yield.