Relationships between Bacterial Leaf Blight and Other Diseases Based on Field Assessment in Indonesia

抄録

Rice diseases cause significant yield losses in Asia, particularly in the tropical regions. A field assessment of their severities and incidences was conducted in Cianjur, West Java, Indonesia, to determine the relationships between bacterial leaf blight (BLB), the most common disease in the preliminary investigation, and other diseases in the region. Six sites with a total of 22 rice paddies were sampled wherein a total of 1,609 tillers were evaluated at the harvest stage. The Ciherang variety was the most common of the six varieties grown in these sites. BLB and narrow brown spot (NBS) were prevalent in all sites. Severe NBS incidence was positively correlated with severe BLB, suggesting that the two diseases might be associated with each other. BLB severity assessment at harvest revealed that the disease had an inverse correlation with tiller weight, but only a minor impact on the grain yield of rice. BLB had a higher negative correlation with the chlorophyll contents than other diseases, and thus, may indicate the effect of the bacterial infection on leaves that had reduced their greenness.