In-vitro suppression of Sclerotium rolfsii using fungicides, botanicals, and bioagents in Brinjal (Solanum melongena L.)

Abstract

The present study was conducted to evaluate the in vitro effectiveness of various fungicides, botanical extracts, and biological control agents against the soil-borne fungal pathogen responsible for collar rot disease in brinjal. Collar rot significantly reduces plant vigor and productivity, making its management essential for sustainable cultivation. In this investigation, seven fungicidal formulations, ten plant-derived extracts, and nine microbial bioagents were assessed under laboratory conditions using poisoned food and dual culture techniques. Among the tested fungicides, the combination of kresoxim-methyl and hexaconazole showed the highest inhibitory effect on fungal growth, followed by carbendazim combined with mancozeb. These treatments exhibited strong fungistatic properties, significantly reducing pathogen development. Among botanicals, the leaf extract of datura and fruit extract of carissa demonstrated the most notable antifungal activity, effectively restricting the growth of the test fungus. This indicates the potential of bioactive compounds present in these plants to act as natural fungicides. In terms of biological agents, certain bacterial and fungal strains showed significant antagonistic effects. Specifically, strains of bacillus and pseudomonas exhibited maximum inhibition of the pathogen in dual culture assays by forming distinct inhibition zones. These beneficial microbes offer potential alternatives to synthetic chemicals through their natural suppressive abilities. The results of the study revealed variation in efficacy among chemical, botanical, and biological treatments, underlining the potential for their integrated use in collar rot management. The findings support the development of environmentally friendly and sustainable strategies to control collar rot disease in brinjal. Incorporating effective bioagents and plant extracts with selective fungicides could help reduce chemical dependence and contribute to improved crop health and yield stability under field condition.