云南高原粳稻品质特性分析

采用表型主成分及聚类分析法，对76个云南高原粳稻的11个品质性状进行了分析。结果表明，（1）直链淀粉含量的平均值达食用稻品种品质1级标准，糙米率、透明度、碱消值和胶稠度达2级标准，精米率达3级标准，其余品质性状的平均值均在3级以下。品种间变异最小的品质性状是糙米率和碱消值，变异最大的是垩白度，其次是垩白粒率。（2）稻米品质性状间存在复杂的相关关系。（3）在选出的6个影响云南稻米品质的主因子中，精米率、垩白粒率和垩白度因子对稻米品质的累积贡献率为49.6%。（4）76个云南粳稻聚为4类，其中第一类包括52个品种，表明遗传距离近，遗传基础狭窄。在今后的云南粳稻品质育种中，应降低垩白粒率和垩白度，提高精米率和整精米率，同时拓宽遗传基础。

Analysis on Japonica Rice Grain Quality Traits of Yunnan Plateau

Eleven grain quality traits of 76 cultivars (lines) from Yunnan Provincial were analysed using the method of phenotypic principal component and cluster analysis. The results indicated that: (1) The mean of amylose content and milled rice rate met 1 and 3 level of edible rice grain quality standard, respectively. And those of brown rice rate, transparency, alkali digested value and gel consistency fit 2 level of that standard.Whereas those of other traits were below 3 level. Among variation coefficients of the grain quality traits, those of brown rice rate and alkali digested value were lowest,,while that of chalky area was highest, and the follow was chalky rice rate . (2) There existed complex relationship among rice grain quality traits. (3) The cumulative contribution rate of milled rice rate, chalky rice rate and chalky area to grain quality was 49.6% among six principal component factors affecting grain quality traits. (4) 76 cultivars (lines) could be classified into four groups according to genetic distance. There were 52 cultivars in No.1 groups, indicating near genetic distance and narrow genetic basis among most of the cultivars. In order to improve the grain quality of Yunnan japonica cultivars, chalky rice rate and chalky area should be reduced while milled rice rate and head rice rate are necessary increased .At the same time, it is also important to broaden the genetic basis in japonica rice breeding.