江苏省中籼水稻品种演进过程中米质的变化

Changes in Grain Quality during the Evolution of Mid-Season Indica Rice Cultivars in Jiangsu Province

以江苏省近60年来各阶段具有代表性的13个中熟籼稻品种(含杂交稻组合)为材料,依据品种种植年代结合株型特点将其分为早期高秆、矮秆、半矮秆常规稻、半矮秆杂交稻和超级稻5个类型,研究了品种演进过程中米质的变化。结果表明,稻米的碾磨品质(糙米率、精米率和整精米率)在同一类品种间有较大差异,在品种演进过程中无明显变化。与早期品种相比,现代品种(半矮秆杂交稻和超级稻)稻米的垩白度显著降低,崩解值变大,消减值变小,稻米中的清蛋白、谷蛋白、赖氨酸、甘氨酸和精氨酸含量显著增加,醇溶蛋白含量显著降低。随着品种演进,产量逐步提高,其原因主要是总颖花量的增加及每穗粒数的显著增多。说明中籼水稻品种演进过程中,米质和产量协同提高。

Improvement in rice quality is very important in rice production. However, little is known about the changes in rice quality during the evolution of cultivars. In this study, 13 typical mid-season indica rice cultivars （including hybrid combinations） applied in the production in Jiangsu Province during the last 60 years were used. These cultivars were classified into five types of early tall cultivars, dwarf cultivars, semi-dwarf cultivars, semi-dwarf hybrids, and super rice according to their application times, plant types and genotypes. All the tested cultivars were grown in the field and the evolution characteristics of the grain quality and yield were investigated. The milling quality （brown rice rate, milled rice rate, and head milled rice rate） differed within the same type of cultivars, but showed no significant differences between types. Compared with those of old cultivars （early tall and dwarf cultivars）, the chalkiness, setback values, and prolamin protein content in grains were significantly decreased, whereas the breakdown values and the contents of albumin and glutelin proteins, lysine, glycine, and arginine were significantly increased in grains of modem cultivars （semi-dwarf hybrids, and super rice）. Grain yield was progressively increased with the evolution of the cultivars. The increase in grain yield was mainly attributed to the increase in total number of spikelets, which resulted mainly from large panicles. The results suggest that both quality and yield are improved during the evolution for mid-season indica rice cultivars.