Abstract
1. The Leaf blight organism of rice (Xanthomonas oryzae) assembles on the growing roots of rice plant and some weeds unspecifically.
2. It seems that the aggregation of.the organism on the plant roots is due to the root exudating materials which are permeable to cellophane membrane.
3. The root of rice plant exudate some kinds of amino acid, sugar and some fluolescent materials under U.V. ray into the culture solution. Eventhough these materials are not the direct factor for the aggregation, at least these will be favourable to the nutrition and survival of the microorganism.
