Antifungal activity of local isolates of Beauveria bassiana (Balsamo) Vuillemin against Verticillium dahliae Kleb. causing wilt disease of cotton

Abstract

BackgroundVerticillium dahliae Kleb. is a soil-borne pathogen with a broad host spectrum and causes yield losses in cotton cultivation worldwide. Beauveria bassiana is an environmentally friendly entomopathogenic fungus (EPF) that has been recognized, used and studied for many years.ResultsAs a control, all local of B. bassiana isolates inhibited mycelial growth of the pathogen at different rates. The highest percentage of inhibition against non-defoliating (PHCVd3 isolate) and defoliating (PHCVd47 isolate) pathotypes was determined in Bb18 (85.3; 81.7%) and Bb1 (82.3; 77.5%) isolates, respectively, when applied 2 days ago. Isolates Bb1 (80.6%) and Bb18 (77.8%) had the highest percentages of inhibition against the PHCVd3 isolate, and Bb18 (75.8%) against isolate PHCVd47, when EPF and pathogen were applied at the same time.ConclusionsBb18 and Bb1 isolates of B. bassiana showed a hope against both pathotypes of wilt disease caused by V. dahliae under in vitro conditions. Especially, B. bassiana was observed to induce higher inhibition rates, when EPF isolates developed in Petri dish 2 days before the pathogen.