Abstract:
Helicoverpa armigera is a serious pest of Cajanus cajan in many parts of world. Rapid
development of resistance against number of insecticides and cry toxin-based biocontrol
agents has led to search for biocontrol agents with alternative mode of action. The ability of
chitinolytic bacteria to degrade vital chitinous structure in insects suggests their potential in
insect control. The present investigation was carried out to study insect control potential of a
high chitinase producing bacterium, Paenibacillus sp. D1. Biocontrol studies with Helicoverpa
larvae showed Paenibacillus sp. D1 and its chitinase to be potent antifeedant that reduced the
feeding rate and body weight of the larvae. The decreased body weight was attributed to
hydrolysis of the chitinous structures of the larvae. This was evident from decrease in the total
chitin content and increased mortality of the larvae fed on the leaves treated with Paenibacillus
sp. D1 and chitinase as compared to untreated controls. A combined dose of Paenibacillus sp.
D1 or its chitinase with an organophosphate insecticide, acephate, was found to be more lethal
than their individual treatments suggesting integrated insect control potential of the bacterium.
Description:
Acknowledgments:
The authors would like to acknowledge the help and support
of Pulse Research Station, Model farm for providing H.
armigera larvae and Dr. Kuldeep Patel for his help in statisti cal analysis of data.
Disclosure statement:
No potential conflict of interest was reported by the authors.
Funding:
The authors would like to acknowledge Gujarat State Bio-technology Mission (GSBTM), Department of Science and Technology, Government of Gujarat and UGC, Government
of India, for financial assistance under FAP-2014 (GSBTM/
MD/PROJECTS/SSA/1400/2014-15) and Minor Research
Grant (File no. 47-568/13WRO), respectively.
