Distribution and bio-prospecting of Native Entomopathogenic Nematodes (EPNs) from Southern Rajasthan, India

Abstract

Entomopathogenic nematodes (EPNs) are insect-parasitic nematodes that function as effective biological control agents against a wide range of insect pests.Owing to their eco-friendly nature and high pathogenicity; they are considered important components for sustainable and eco-friendly pest management strategies in modern agriculture. The present investigation aims to reduce the use of harmful chemical insecticides by usingnative and effective isolates of EPNs. So, we conducted multiple surveysfor isolation and identification of native potential EPNs isolatesfrom various districts of southern Rajasthan particularly from Udaipur, Chittorgarh and Pratapgarh. Out of total 77 soil samples collected from various habitats, 7 samples were found positive for EPNs infestation. Upon analysis, the highest frequency of EPNs occurrence was observed 11.36 percent in Udaipur district followed by 7.40 per cent in Chittorgarh district and zero in Pratapgarh district. The maximum (20.00 %) occurrence of EPNs was found in samples collected from the orchard ecosystem (fig, sapota and guava) followed by uncultivated land (10.52%). All seven isolates were evaluated for their bio-efficacy against greater wax moth, Galleria mellonella under in-vitro conditions. By evaluating the efficacy, two most virulent isolates, i.e. Heterorhabdistis indica P-1 and Oscheius tipulae P-2, were considered and identified on morphological and molecular characterization.