Major Rice Diseases in Ethiopia: Current Status, Impacts, and Integrated Management Strategies
DOI:
https://doi.org/10.24925/turjaf.v14i6.1741-1748.8631Keywords:
Rice pathogens , Disease resistance , Food Security , Yield loss , Integrated Disease ManagementAbstract
Rice production in Ethiopia, a cornerstone of the nation's food security strategy, faces severe and escalating constraints from a complex of fungal, bacterial, and viral diseases. This comprehensive review synthesizes current knowledge on the status and management of these biotic threats across diverse Ethiopian agro-ecologies. Rice blast, caused by Pyricularia oryzae, remains the most devastating pathogen, capable of causing total crop failure under conducive conditions. Concurrently, brown spot (Bipolaris oryzae) persists as a pervasive issue, strongly linked to widespread soil nutrient deficiencies, particularly silicon. The ongoing intensification of rice cultivation has further promoted the emergence of new challenges, including sheath blight (Rhizoctonia solani), bacterial leaf blight (Xanthomonas oryzae pv. oryzae), and sheath rot disease complexes. These diseases collectively cause substantial yield losses, estimated between 20% and 70%. Alarmingly, previously minor diseases such as false smut, bakanae, kernel smut, and viral infections like rice yellow mottle virus (RYMV) are being reported with increasing frequency, compounding the threats to productivity and farmer livelihoods. This review critically examines the etiology, epidemiology, and economic impact of these pathogens. Additionally, it emphasizes that mitigating the effects of these multifaceted disease challenges requires a holistic, Integrated Disease Management (IDM) framework. Effective and sustainable control must strategically combine host plant resistance, optimized cultural practices, biological control agents, and judicious chemical interventions, all tailored to the unique socio-economic and environmental contexts of Ethiopian rice farming systems to ensure long-term yield stability and food security.
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