A Study on the Phage-Bacteria Relationship of Xanthomonas translucens f. sp. oryzicola (Fang et al.) Bradbury

Abstract

Phage population in the drainage canal of IRRI Farm was highest from August to October amounting to 6-7×10³/ml. The population in the water of reservoir was the next highest. The population peak in the large irrigation canal came a few months earlier than those in the drainage canal and the reservoir. The count was, however, lowest among the 3 sites. Many new phage strains with the different host range patterns were isolated from the plates used for the above phage population survey as well as from the stock cultures of 6 phages studied by Goto. The host srange pattern of these new phages were so diverse that it was almost impossible to classify them into groups with the host ranges. The reason why the host range patterns were so diverse, and new patterns were so often detected from the stock cultures was studied. It was proved that the colony type mutation associated with the phage susceptibility was involved as one of the most important factors controlling the above phenomenon.