Identification and Characterization of Triple Action Bioagents (TAB) and Their Potency against Fusarium Wilt of Lentil

Abstract

Fusarium wilt is a severe disease that plays a significant role in reducing the yield of lentil. Under favorable conditions for disease growth, the disease can cause complete crop failure and can be a crucial limiting issue for lentil cultivation in specific geographical zones. The current work focused on isolating potentialbio-agents exhibiting copper oxychloride resistance and evaluating their efficacy in seed treatment for ecologically sustainable management of Fusarium wilt of lentil. Seventy biocontrol agent isolates were isolated and tested for resistance by growing them on Potato Dextrose Agar medium (PDA) amended with copper oxychloride at the rate of 2500 ppm. Isolate-H10 and isolate-C9 showed more excellent compatibility with copper oxychloride fungicide with 69 mm and 65 mm radial growths, respectively. The isolates H10 and C9 had the highest inhibitory percentages of 84.30% and 83.94% against Fusarium oxysporum f. sp. lentis, respectively, and the highest phosphorus solubilization index (PSI). Primers (ITS 1 and ITS 4) identified these putative bioagents as Trichoderma harzianum isolate skua-tab-1 and Penicillium crysogenum strain Tab2. Sequences were submitted to the NCBI and assigned the accession numbers MK414603 and MK418066. In pot culture, these isolates also demonstrated their superiority in reducing the disease incidence and severity if seeds were treated with H10 and C9 alone or in combination with copper oxychloride fungicide. The two isolated bioagents exhibit three fundamental properties: compatibility with copper oxychloride, antagonistic activity toward the pathogen fall armyworm, and the ability to dissolve phosphorus minerals.

Keywords

• bio-agents
• copper oxychloride
• phosphorus solubilization
• <i>Fusarium</i> wilt
• lentil