Microbiology and Biotechnology Research: An Overview Vol. 8

Soybean (Glycine max L. Merrill.) is adversely affected by several pathogenic fungi, most of which are seed-borne and responsible for considerable qualitative and quantitative losses. To address this issue, an in vitro study was conducted to evaluate the efficacy of fungicides against three major seed-borne pathogens, namely Fusarium verticillioides, Macrophomina phaseolina, and Alternaria alternata, using the Poisoned Food Technique. The experiments were arranged separately under a Completely Randomised Design (CRD), with each treatment replicated three times. A total of seven seed dressing fungicides at their recommended field dosages were evaluated in vitro by the poisoned food technique, against three major seed-borne fungi, viz., F. verticillioides, M. phaseolina and A. alternata of soybean. The findings revealed that all seven seed-dressing fungicides tested significantly inhibited the mycelial growth of the pathogens compared to the untreated control. For Fusarium verticillioides, Tebuconazole 25% WG and Carbendazim 12% + Mancozeb 63% WP were the most effective, achieving 100% inhibition. In the case of Macrophomina phaseolina, Mancozeb 75% WP, Carboxin 37.5% + Thiram 37.5% WP, and Carbendazim 12% + Mancozeb 63% WP provided complete inhibition. For Alternaria alternata, Carboxin 37.5% + Thiram 37.5% WP was the most effective (85.93% inhibition), followed by Tebuconazole 25% WG (38.52% inhibition), while the remaining fungicides were comparatively less effective. In summary, although all fungicides suppressed fungal growth to varying degrees, the study identified Tebuconazole 25% WG, Carbendazim + Mancozeb WP, and Carboxin + Thiram WP as the most promising options, with pathogen-specific effectiveness.