Survey for the incidence of collar rot of groundnut caused by Aspergillus niger in Karnataka

Abstract

Groundnut (Arachis hypogea L.), an economically important legume crop, is cultivated largely for its high-quality edible oil and easily digestible proteins. Various pathogens have been reported to affect the groundnut crop, among them, the fungal disease, i.e., Collar rot disease caused by Aspergillus niger Van Teighem, causes a significant yield loss. Under Indian conditions, the incidence of disease appears to be higher in the rainy season than in the rabi/summer. Keeping these points in view, a survey was undertaken during Kharif, 2023, which revealed that all of Karnataka's major groundnut farms were affected by the collar rot. The village wise mean incidence ranged from 19.30 to 21.87 per cent. The highest disease incidence was found in Raichur district (21.84%), followed by Chitradurga (21.47%), Vijayanagara (21.27%), Yadgir (19.98%) and Tumakur (19.30%) was recorded. The prevailing symptoms of collar rot such as yellowing, wilting, drying and Black circular ring spots on collar region, and finally death of the plant, were observed. The infected plant samples were then collected and isolation was done on the PDA medium. And also in vitro Dual culture efficacy of isolated of native PGPRs and endophytes were tested against the A. niger. amoung 18 isolates of PGPRs and 15 isolates of endophytes, 12 isolates are showing maximum inhibition.