Management of rice blast disease (Pyricularia oryzae) using formulated bacterial consortium

Rice blast caused by Pyricularia oryzae is a major disease affecting rice production grown in upland and wetland rice. Application of beneficial bacteria as seedling root dip and spraying method to protect against the disease may be an alternative strategy to chemical control. This research was aimed to explore the bacterial consortium that may control blast disease on rice plants. In this study, the following bacterial cultures and their consortiums were used: Bacillus firmus E65, Serratia marcescens E31, Pseudomonas aeruginosa C32b, Bacillus cereus II.14, and its combination for their suppression ability against P. oryzae under in-vitro conditions. The results showed that A2 (Bacillus firmus E65) and A6 consortium (Bacillus firmus E65, Bacillus cereus II.14, and Pseudomonas aeruginosa C32b) significantly reduced the mycelial growth of P. oryzae with the percentage inhibition of 73-85% and 66-83%, respectively. Further greenhouse testing conducted with use of formulative preparation of the two selected best treatments using talc, bentonite, palm oil, and suspensionbased carriers showed that spraying with suspension formulation had good effect in suppressing blast disease compared with that of other carriers evaluated.