Abstract

The bacterial isolate Serratia entomophila AB2 having multidimensional attributes like larvacidal activity and nutrient-solubilizing capability was used to test its effect on productivity of groundnut. Two different inorganic carriers (talcum powder and vermiculite) based formulations of the bacterial isolate were also tested along with the unformulated product and 100% recommended dose of NPK (60:60:50) for comparative study. S. entomophila AB2 (unformulated) efficiently minimized lepidopteran pest infestations when compared with control (larval stage of Heliothis armigera, 27%; Spodoptera litura, 30%; Plutella xylostella, 23%). The strain also increased seed germination by 10%, increment in shoot weight was by 100% and enhancement of seed weight was by 120% in comparison to negative control in a field trial. But, both of the inorganic carrier based formulations showed better results in respect to pest control and productivity compared to the unformulated bacterium. Among the two formulations used in this study, vermiculite based formulation was found effective in terms of pest control and productivity. Consequently, a vermiculite based formulation of S. entomophila AB2 could be effectively used at the rate of 3.6 qthec^-1 for quality and yield enhancement of groundnut.

Key words: Serratia entomophila AB2, fermentation, pesticide, nutrient solubilizer, integrated crop management (ICM) productivity.