Biocontrol Potential of Endophytic Bacteria Isolated from Healthy Rice Plant against Rice Blast Disease (Pyricularia oryzae Cav.)

Abstract

Isolation was attempted to collect endophytic bacteria as potential biocontrol agents against rice blast disease (Pyricularia oryzae Cav.). The disease is one of major threats in rice production as it can cause 100% yield loss. Concern on the environment and human health has led to the searching of alternative controlling method to replace the commonly used pesticide-based method. Endophytic bacteria are bacteria that have intimate relationship with their host without inducing any pathogenic symptom. The use of endophytic microbial as biocontrol agent has its own advantages as the microbes are more easily to adapt to the environment needed by the host plant. We evaluated endophytic bacteria isolated from healthy rice plants and tested for their potential biocontrol activity using dual culture assay. Ten isolates were found to inhibit the growth of P. oryzae of more than 50%. Microscopic observation showed that they were able to cause the mycelia malformation of P. oryzae. Further work is currently in progress to determine their effectiveness in the pot trial. Keywords: Endophytic bacteria; Pyricularia oryzae; biocontrol.