Comparative evaluation of management modules against Maydis leaf blight disease in maize (Zea mays)

Maydis leaf blight (MLB) is a prevalent disease, caused by the necrotrophic plant pathogen Bipolaris maydis (Nisikado and Miyake), affecting maize worldwide. Depending on environmental conditions, MLB can lead to yield losses of up to 40% or more. The existing management approach of chemical disease control is expensive and unsustainable. Hence the need to evaluate an integrated approach of chemical and biocontrol/botanical agents for its sustainable management. This study aimed to assess the efficacy of three management modules namely organic, chemical, and integrated disease management (IDM) against this disease in maize. The effectiveness of three modules was tested at three hot spot locations (Ludhiana, Karnal, and Delhi), during 2019 and 2020. The chemical module was most effective in controlling the disease followed by the IDM module, with control rates of 54.16% and 45.87% in Ludhiana and 52.92% and 44.69% in Karnal, respectively. Conversely, the organic module showed the lowest effectiveness. Notably, at the Delhi location, the standard control (foliar spray with Mancozeb 75WP@ 2.5 g/l water) proved most effective, achieving a disease control percentage of 64.29%, followed by the IDM module at 50.00%. The chemical module exhibited the highest increase in yield at Ludhiana (86.47%) and Karnal (52.92%), compared to other treatments. Overall, based on location-wise averages, the chemical module gave the highest mean percent disease control at 52.36% and mean percent yield increase at 49.18%. This study emphasizes the benefits of integrated disease management and underscores the enhanced efficacy of chemicals when compared to the positive control.