Speaker
Description
Effective management of bacterial panicle blight (BPB) is critical to minimizing yield losses, yet current strategies are limited by a scarcity of resistant rice cultivars. Furthermore, while the antibiotic oxolinic acid is a key chemical countermeasure globally, its agricultural use remains unregistered in several countries. Therefore, sustainable biocontrol alternatives are urgently needed for effective BPB management. This study evaluated the field efficacy of bioformulations consisting of the antagonistic bacterium Bacillus sp. B1-2-11 and chitosan nanoparticles (CNP) for managing BPB in paddy rice. Field experiments were conducted during the 2025 off-season at MARDI Seberang Perai using an open-field, small-scale cultivation system. The treatments evaluated the formulations administered either as individual or combined applications via an initial seed treatment and two subsequent foliar applications. Results were compared against current standard operating procedures (SOP) utilizing copper and the antibiotic oxolinic acid. All bioformulated treatments significantly reduced BPB incidence and severity compared to the untreated control. The combined seed and foliar application of Bacillus sp. B1-2-11 achieved the lowest disease incidence (19.9%) and severity score (2.5), demonstrating comparable efficacy to commercial standards. Regarding productivity, the Bacillus sp. B1-2-11 + CNP (seed and foliar) treatment achieved a prominent grain yield of 7.74 t/ha, closely matching the copper SOP (7.97 t/ha) and oxolinic acid SOP (7.50 t/ha). These findings indicate that the nano-biocontrol formulation offers a promising, environmentally sustainable alternative to chemical bactericides for BPB management, providing consistent disease reduction while maintaining high yield potential under field conditions.
