Matrix Science Pharma (MSP)

ABSTRACT

Bacterial leaf blight (BLB), caused by Xanthomonas oryzae pv. oryzae (Xoo), remains one of the most destructive diseases of rice in Southeast Asia, including Malaysia, where yield losses can reach 70%. The extensive reliance on synthetic bactericides has raised concerns regarding environmental contamination and the emergence of resistant pathogen strains, highlighting the need for sustainable disease management alternatives. This review evaluates the biocontrol potential of leaf extracts from Acacia mangium, Anacardium occidentule, and Swietenia mahagoni against Xoo, with emphasis on their phytochemical composition and antibacterial mechanisms based on published in vitro studies. Available evidence indicates that A. mangium exhibits the strongest antibacterial activity, including pronounced bactericidal effects and inhibition of Xoo biofilm formation. A. occidentale demonstrates moderate antibacterial activity, supported by a broad spectrum of bioactive phenolic compounds and antioxidant properties. In contrast, S. mahagoni shows limited or pathogen-specific antimicrobial activity, with no consistent inhibition of Xoo reported, suggesting variable effectiveness against different target pathogens. Collectively, these findings highlight the potential of selected plant extracts, particularly A. mangium and A. occidentale, as promising candidates for further development as plant-based biocontrol agents. Future research should focus on formulation optimisation and in vivo validation to support their integration into integrated pest management (IPM) strategies for sustainable rice disease control.