ABSTRACT
The study aimed to assess the impact of different combinations of cultivar mixtures on finger millet blast epidemics without affecting yield. The research employed Disease Progress Curves (DPCs) such as AUDPC, rAUDPC, and sAUDPC to evaluate leaf, neck and finger blast epidemics' severity at various time intervals. Treatments involved mixtures of pre-released cultures and commercial varieties, combined with resistant cultivars in ratios of 1:1 and 2:1 to combat blast disease. These mixtures were compared with monoculture performances (resistant and susceptible checks) and fungicide treatments. The mixture of pre-released cultures (TNEc 1285 + TNEc 1294 + TNEc 1310) combined with the resistant cultivar GE4449 at a 1:1 ratio demonstrated the most significant impact in reducing the Area Under Disease Progressive Curve (AUDPC) values for all three blast types while maintaining consistent yield. This treatment exhibited results comparable to fungicide (Tricyclazole 75% WP) sprays across trials conducted from September to December in both 2020 and 2021. Economically, the cost-benefit ratio favoured the culture composite despite its delayed onset and slower progression during disease epidemics under field conditions. The mixture of cultures demonstrated sustainable yield without requiring significant additional input costs or frequent fungicidal application in both trial periods. This suggests a promising and cost-effective approach to managing finger millet blast epidemics while maintaining yield stability in agricultural practices.
ABSTRACT
The antagonistic Bacillus spp. is known well for the production of versatile antimicrobial biomolecules with broad spectrum of action against different types of plant pathogens. Considering the significance of metabolically active biomolecules, attempts were made to decipher the anti-oomycete nature of biomolecules produced by Bacillus atrophaeus NMB01 during di-trophic interaction with Phytophthora infestans. Ten biomolecules produced by B. atrophaeus NMB01 during di-trophic interaction with P. infestans were docked against the twelve target proteins of P. infestans. Molecular docking of biomolecules reported trioxsalen and corynan-17-ol,18,19-didehydro-10-methoxy-acetate(ester) as best hits with highest binding energy in the range of - 7.5 to - 5 kcal/mol against target proteins of P. infestans. Comparatively less binding energy was observed for commercially available fungicides mandipropamid and metalaxyl on docking against the target proteins of P. infestans. We also confirmed the direct impact of trioxsalen andcorynan-17-ol, on P. infestans under in vitro with 66% and 50% inhibition of mycelial growth of P. infestans, respectively. This is the first study attempted to untangle the role of bioactive anti-oomycete compounds produced by B. atrophaeus strain NMB01 during di-trophic interaction with P. infestans against late blight pathogen P. infestans infecting potato. From the present study, we conclude that the biomolecules, trioxsalen and corynan-17-ol, can be explored for the management of P. infestans, the incitant of late blight of potato. Supplementary Information: The online version contains supplementary material available at 10.1007/s12088-022-01044-7.
