Abstract
1. Rice plants in various stages (seedling, tillering and heading stages), were inoculated with conidia of Helminthosporium oryzae (Cochliobolus miyabeanus) and incubated for 8, 16 and 24 hrs. at 28°C. The preparation of protein was carried out by a modified method of Danielsson as shown in Fig. 1, and after the preparation, protein was fractionated by employing paper-electrophoresis and column chromatography.
2. The paper electrophoretic analysis showed that protein from rice plants had 5 fractions determined by densitometric scanning. However, there was no characteristic difference between healthy and diseased leaves.
3. By the step-wise elution from DEAE-cellulose column with 0.01-1.0M tris buffer solutions (pH 7.2), 6 fractions were obtained. Among them, 3 fractions were changed quantitatively with the infection. Although the different patterns of protein fraction were given with the growing stages and culture conditions of the rice plant, the protein fractions eluted with 0.5M and 1.0M tris buffer were always found to be changed quantitatively after the inoculation. The protein from 0.5M tris buffer elution increased in the leaves of susceptible variety, Asahi, 24 hrs. after inoculation. In the heading stage of rice plants, the increment of protein was noticeable 16 hrs. after inoculation.
