Molecular characterization of Insect Parasitic nematodes, and assonated Symbiotic bacteria as Ecotoxic effect of Invasive insect larvae

Abstract The agro-climatic zones survey was conducted diversity and frequency of endemic entomopathogenic nematodes (EPNs) in Apple orchards in Rajgarh, western Himalayas. Isolated EPNs have been used as an active biocontrol agent against T. absoluta and S. frugiperda. The total survey of 42 locations apple orchards were collected from which 281 soil samples and tested 7 soil samples are positive for the presence of EPN. Native isolated strains morphologically and molecular identification of nematodes, insect and bacterial sequencing and characterisation of the internal transcribed spacer (ITS) 18S, 12S and 16S region was used to identify all nematode isolates, insects and bacterial strains upto species level (S. feltiae UHF-HR1, H. bacteriophora UHF-HR2; T. absoluta SN1, S. frugiperda SN2; X. bovienii R1, P. luminenscens R2). There have been used as an active biocontrol agent against T. absoluta and S. frugiperda. The bioassay of after 72 hours with different concentrations of 10, 20, 40, 80, and 160 IJs/cm2, the data susceptibility of T. absoluta 4th larval and S. frugiperda 5th instar to infection with the nematode S. feltiae and H. bacteriophora mortality range 74.12 to 90.00 percentage mortalities. To assess the lethal concentration of entomopathogenic nematodes to insect larvae, a toxicity evaluation the LD50 and LD90 for S. feltiae and H. bacteriophora doses in final instar the best larvicidal activity was obtained during the 72-hour exposure period, The susceptibility of infection was found to be greater than 80%. The strains R1 and R2 bacterial isolates were bioassay experiments were X. bovienii and P. luminescens of treatment throughout the investigation, daily larval mortality ranged from 0.00 to 90.00 percent. Our analysis confirmed the steep inclination of S. frugiperda and T. absoluta. S. feltiae UHF-HR1 and H. bacteriophora UHF-HR2 & Photorhabdus and Xenorhabdus were utilised, with 90 percent control over both entomopathogenic nematodes and their symbiotic bacterial strains.