Abstract
Overwintering of the causal organism (Xanthomonas oryzae) of the bacterial leaf blight of rice plant, seems to be carried out by two forms: namely the one dried and dormant form and the other vegetative form. In th case of the dried form, the conglomeration of the bacterial cells with each other is necessary to prolong their longevities.
When once changed to this form, the organism was dead gradually if it absorbed plenty of water under low temperature in winter. That is, in the rice field, the organism once change its form to dried state in the diseased leaves of rice or marsh grass (Asprella oryzoides), will Hip gradually during winter due to the repeated moistening by rain.
