Abstract

                                The ability of Xanthomonas pv. oryzae to digest starch has been used to detect the presence of the pathogen in rice (Oryzae sativa L.) seeds with the use of SX agar. Zones of starch hydrolysis appeared around seeds containing pv. oryzae 481 h after the seeds were plated onto SX agar. By this method 12 pathogenic strains of pv. oryzae were detected and characterised from seeds of 19 cultivars of rice. Starch digesting strains with yellow colonies and tested for their aerobic nature were found to be pv. oryzae. This seod-plating procedure was used to monitor the extent of seed Infection and to examine the variability among the pathogenic strains of pv. oryzae from Southern India.

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