Bioextracts enabled eco-friendly management of Maydis leaf blight disease of maize

An investigation over three consecutive years (2016–2018) evaluated eco-friendly management strategies for Maydis leaf blight (MLB) of maize caused by Bipolaris Maydis under field conditions. Ten treatments—nine herbal extracts and one animal refuse (cow urine)—were tested at varying concentrations. Azadirachta indica (neem) leaf extract was most effective, providing 20.75% disease control and a 52.75% yield increase, followed by Allium sativum extract with similar disease control and a 42.64% yield gain. Polyalthia longifolia and Parthenium hysterophorus extracts at 10% concentration showed moderate efficacy, achieving 15.09% disease control. Genotype (G) effects and genotype-by-environment (G × E) interaction assessed via GGE biplot revealed two distinct environmental groups for disease severity (Environment 2–Environment 3 versus Environment 1), while all environments clustered together for grain yield (E1–E3). The study highlights natural bioextracts as sustainable MLB management alternatives that avoid environmental pollution.