ABSTRACT

Okra, one of the most important vegetable crop is grown under both rainfed and irrigated conditions in different parts of the country. Generally the crop is being affected by many foliar diseases which limits its production and productivity. A study was conducted during 2023-24 at MARS, Dharwad to evaluate the efficacy of botanicals, bioagents and ITKs under both in vitro and field conditions along with screening of genotypes against powdery mildew and Alternaria leaf spot of okra. Under in vitro studies among botanicals, margo neem (Azadirachtin 0.15%) and perfekt (herbalmixture) @ 1 per cent was found effective, among bioagents, Trichoderma harzianum and Pseudomonas fluorescens @ 10g/l and among ITKs, panchagavya and cow urine @ 15 per cent was found effective against both the pathogens Erysiphe cichoracearum and Alternaria alternata causing powdery mildew and Alternaria leaf spot respectively.
Field evaluation of these in vitro effective biorationals revealed that the treatment involving first spray of margo neem (Azadirachtin 0.15%) @ 1 per cent followed by second spray of Trichoderma harzianum @ 10g/l recorded the least disease severity of powdery mildew (43.99 %) and Alternaria leaf spot (34.79 %) with highest per cent disease reduction over control, which was statistically found on par with the standard check (two foliar sprays of difenoconazole 25% EC @ 0.1%) and this treatment also recorded the high yield (13.94 t/ha) , high net returns and benefit cost ratio. Among the twenty five genotypes screened, the genotype ABL-4 recorded highly resistant reaction to powdery mildew and moderately resistant reaction to Alternaria leaf spot. Whereas, ABL-1 and ABL-3 exhibited moderate resistance to both powdery mildew and Alternaria leaf spot which provides valuable sources for breeding programmes aimed at developing resistant okra cultivars for multiple diseases.