s Development of Bio-formulations of Piper sarmentosum Extracts Against Bacterial Rice Diseases

Background: Bacterial leaf blight and sheath brown rot caused by Xanthomonas oryzae pv. oryzae (Xoo) and Pseudomonas fuscovaginae, are severe diseases of rice (Oryza sativa L.) causing significant losses in both yield and quality. To evaluate more effective control measures, we evaluated bioformulations formulated from Piper sarmentosum Roxb. (Piperaceae) (pokok Kaduk or wild betel) leaf extracts in promoting rice seedlings growth and disease suppression. Methods: The bio-formulations were developed using crude plant extracts, (surfactant Emereen 1820 alkylpolyglucoside and Emereen 1604 castor oil ethoxylate), and water. The bio-formulations were applied as seed treatments to evaluate their effects on seed germination and seedling vigour and were then tested for their efficacy to control leaf blight and sheath brown rot of rice under glasshouse conditions. Results: Preliminary laboratory experimental results showed that bio-formulations improved seed germination and seedling vigour. It also enhanced seedling height, root length, seedling and root dry weight compared to the control. A significantly lower disease incidence and severity were observed in rice treated with the bio-formulations under glasshouse condition. Conclusion: The results obtained from this study suggested that the P. sarmentosum extract bioformulations can potentially be applied as bio-pesticides for the management of rice diseases. However, further studies are required to re-evaluate the effects of the formulation under similar field conditions in endemic areas and scale-up possibilities for further applications.