中国主要稻米的粒型及其品质特性

利用近3年全国各地的籼、粳稻稻谷样品5331份(其中籼稻谷3810份，粳稻谷1521份)的米质数据，对我国目前稻米的粒型及其相关品质进行了研究。结果表明，目前生产上应用的籼稻品种的粒长主要有长粒和中粒两种，粒形则以中粒形为主，细粒形为辅；绝大多数粳稻品种的米粒属短、粗类型。籼稻的粒长、粒形均与其整精米率、垩白度、透明度、直链淀粉含量呈极显著负相关，而与胶稠度呈极显著正相关。粳稻的粒长、粒形与其主要品质指标的相关性相对较弱，且其性质也与籼稻的不尽相同。不同粒长组的平均整精米率也不同，其高低顺序是极短、短、中、长、极长，其中粳稻的极短粒与短粒两个类型间的整精米率无明显差别，但两者的整精米率与中粒的差异极显著；籼稻米各粒长组间整精米率的差异均达极显著水平。对各类稻米的品质进行评价的结果显示，粳稻米总体的品质优于籼稻米，有近半数粳稻品种的米质达到了优质米标准，而籼稻仅有1/4达到优质米标准；籼稻米中，极长粒形及长粒形品种中达优质米标准的比率高于中粒形及短粒形的品种。

Grain Types and Related Quality Characteristics of Rice in China

A total of 5331 rice samples, including 3810 indica and 1521 japonica, were collected from China to study their grain types and related quality characteristics. For indica rice, long and middle grains were the two principal types in grain length; the medium was the first key type in grain shape, and the slender was the second one. For japonica rice, the grains of most varieties were short and coarse in length and shape. In indica rice, both grain length and shape were significantly related to head rice rate, chalkiness, translucency, and amylose content(negatively), and gel consistency(positively). In japonica rice, grain length was significantly related to head rice rate and gel consistency (negatively), and amylose content (positively)(P<0.01), grain shape was significantly related to chalkiness(negatively), and amylose content and protein content(positively). There were significant differences in head rice rate among different grain length groups, except short and very short grain groups. The order of head rice rate was adversely accorded with the increase of grain length. The quality of japonica rice was superior to that of indica rice as a whole, near a half of japonica varieties had grain qualities satisfied the superior criteria of China, while only a quarter of indica varieties reached the superior criteria. Among indica varieties, the grain quality of groups with long and extra long grain types were superior to that of groups with middle and short grain types.