Vol. 12, Issue 12 (2023)

Author(s):
Jameela Rasool, Ishtiyaq Ahad, Tarique Hassan Askary, Fahim Jeelani Wani, Khalid Rasool, Nazir Ahmad Ganai and Waseem Ahmad War

Abstract:
The study on biocidal efficacy and reproductive potential of a native strain of entomopathogenic nematode, Steinernema anantnagense against apple leaf roller, Rhopobota naevana under laboratory conditions was carried out at Division of Entomology, FoA, Wadura, SKUAST- Kashmir, India. The EPN isolate was found effective against the insect pest. Mean percent mortality of 3^rd, 4^th and 5^th instar of Rhopobota naevana was 100 percent at the inoculum levels of 200 IJs/grub at 72 hours after inoculation. Percent mortality increased with rise in inoculum levels and exposure time. Median lethal concentration (LC⁵⁰) values of the EPN decreased with the increase in time interval. Calculated value of median lethal time (LT⁵⁰) was directly proportional to the size of the larva. Time consumed by EPN to cause mortality to 3rd instar larva was least followed by 4^th and 5^th instar larva at all the evaluated time intervals. Production of infective juveniles was directly proportional to the size of the host. However, average population of Steinernema anantnagense produced in 5^th instar was highest and was followed by 4^th and 3^rd instar larvae at all the four inoculum levels ie., 50, 100, 150 and 200 IJs per larva.