Field and Multi-locational Study on Efficacy of Native Entomopathogenic Nematodes (Heterorhabditis bacteriophora Poinar) against Termite (Odontotermes obesus Rambur) in Assam, India
Gitanjali Devi *
Department of Nematology, SCS College of Agriculture, Assam Agricultural University, Dhubri-783376, Assam, India.
Badal Bhattacharyya
Department of Entomology, College of Agriculture, Assam Agricultural University, Jorhat-785013, Assam, India.
Snigdha Bhattacharjee
AAU-SMAPRS Buralikson, Golaghat-785630, Assam, India.
Manha Bathari
AAU-ZRS Diphu, Karbi Anglong-782460, Assam, India.
Samiran Pathak
AAU-HRS Kahikuchi, Kamrup-781017, Assam, India.
*Author to whom correspondence should be addressed.
Abstract
Entomopathogenic nematodes (EPNs) are one of the important biocontrol agents against various insect pests. The effects of different doses and time of application of Entomopathogenic nematode (Heterorhabditis bacteriophora Poinar) were evaluated under field condition against termite (Odontotermes obesus Rambur). At 5.0×109 IJs/mound, three-time application at one month interval as soil drenching method were required to cause 60.6 % mortality of O. obesus. Results showed that sequential application of EPN is effective than one time application. The effective dose was further evaluated in three multi-locational trials under different agro-climatic regions of Assam. Results showed that 61.6%, 61.3% and 60.6% mortality of O.obesus was due to the three times application of H.bacteriophora at the dose of 5.0×109 IJs/mound in AAU-HRS Kahikuchi, AAU-SMAPRS Buralikson and AAU-ZRS Diphu, respectively. Both workers and soldiers of O. obesus cadavers had higher progeny production of H.bacteriophora with high persistence in mound soil.
Keywords: Biocontrol agent, Entomopathogenic Nematodes (EPNs), efficacy, mound, Odontotermes obesus, soil drenching method, termite