Studies on the Soft-Textured Rice Kernel : VI. Changes of water content in the ripening process of rice kernel

[摘要] In order to find out the differences of water content between the soft and the hard-textured rice kernels in their ripening process, the present writers compared the rice grains harvested at Fukui and that harvested at Osaka. The former is regarded as soft-textured kernel and the latter as hard one. Experiments were performed on the farm attached to the University of Fukui (Makinoshima-Cho, Fukui City) as representing soft-textured rice producing area and on the field of the Osaka Prefectural Agricultural Experimental Station (Konoikeshinden, Kawachi City, Osaka Prefecture) as representing the other type area. Two varieties, Norin No. I and Yutakasenbon, were used for each of the soft and the hard rice. They were grown under the standard cultivation method for two years 1956-1957. Followings are the results obtained: (1) The water content (percentage and weight of water in one grain) of the soft-textured rice kernel was found generally lower than that of the hard one. (2) The dry matter content (percentage and weight of dry matter in one grain) of the former, on the contrary, was generally higher than that of the latter. (3) It may be said that the differences in the water contents, both percentage and weight in one grain, between those two kinds of rice kernels are determined by the difference of the meteorological factors especially average daily duration of sunshine and air temperature between Fukui and Osaka. From the above results it may be concluded that water content is not the characteristic factor for the soft-textured rice kernel.

[学科分类] 农业科学（综合）