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The microscopic structures of the endosperm of indica rice varieties with different quality be-fore and after gelatinization were observed using scanning electron microscope. The results showed that the de-gree of gelatinization varied in different parts of the grain and in different varieties under the same experimen-tal conditions. The gelatinization of dorsal side was the most complete. Its cells were decomposed totally intopuff-like or flocculent materials. The ventral side gelatinized less thoroughly, appearing agglomerate and somecell frames were still visible. The middle part gelatinized most incompletely and the cells were still integrated.Evident differences in gelatinization were observed among different varieties, the dorsal, ventral and middleparts of high quality varieties gelatinized more thoroughly than those of the corresponding parts of low qualityvarieties respectively. An obvious concavity often appeared in the middle of the cross-section of the low qualitygrains while the cross-section of high quality grains was normally flat. The same phenomenon was noted whencomparing the early maturing indica rice and the late maturing indica rice. Varietal difference of gelatiniza-tion in dorsal sides was not as distinct as in middle parts and ventral sides. The difference among dorsal side,middle part and ventral side in gelatinization was greater in low quality grains than that of high quality grains.In addition, a lot of ruptured cells were observed in the cross-section of high quality rice, while few of themcould be found in the low quality rice. Apparently, the number of ruptured cells is positively correlated withrice quality. Quality of rice grain also has positive correlation with the rate of water absorption and extension. Highrates of water absorption and extension lead to better gelatinization of rice grain, and hence indicate good quality.