Study on the Chalkiness Character of Giant Embryo Rice and Observation on Its Microstructure in Grains

Grain chalkiness greatly affects the grain appearance and milling, eating, cooking, and nutritional qualities, thus it is one of the most important traits of grain qualities. Based on the study of chalkiness characters in endosperm of different giant embryo rice, the relationship between the differences of chalkiness characters in endosperm of different giant embryo rice and the morphological structure, arrangement and development of starch granules in endosperm was clarified, which will lay a solid foundation for further revealing the formation mechanism of chalkiness characters in giant embryo rice and cultivating excellent new varieties of giant embryo rice. In this study, the chalkiness of endosperm (including chalkiness rate, chalkiness degree and chalkiness area) of 16 different rice varieties were investigated and analyzed. The results showed that the chalkiness of endosperm was closely related to the morphological structure and arrangement of starch granules in endosperm cells of different kinds of giant embryo rice, and there were significant differences between the chalkiness of different parts of the same giant embryo rice and the morphological structure and arrangement of starch granules in endosperm cells. Therefore, the results of this study will provide important information for the improvement of quality characters and the breeding of new rice varieties.