冷水胁迫对云南粳稻品质性状的影响

 以11个云南粳稻品种为试验材料，研究冷水胁迫对稻米品质性状的影响以及水稻耐冷性与品质性状冷水反应的相关关系。结果表明，品质性状的冷水反应不仅与品种有关，也与具体的品质性状有关。冷水胁迫使粒宽、千粒重、垩白粒率、精米白度、糙米率、味度值、最高黏度、最低黏度、崩解值、最终黏度显著或极显著降低，使长宽比、整精米率、碱消值、蛋白质含量和消减值极显著增加，而粒长、精米率、直链淀粉含量、到达最高黏度时间（峰值时间）和起浆温度不因冷水胁迫发生明显变化。相关分析表明，成熟期综合耐冷性与稻米的味度值、蛋白质含量、最高黏度和崩解值的冷水反应指数具有显著或极显著相关性。因此，提高育成品种的耐冷性对稳定和改善稻米食味品质具有重要作用。

Effects of Cold Water Irrigation on Grain Quality Traits in japonica Rice Varieties from Yunnan Province, China

The response of grain quality traits to cold water irrigation were studied by using eleven improved japonica rice cultivars from Yunnan Province, China. The results indicated that the response of grain quality traits to cold water irrigation varied in either cultivars or grain quality traits. The grain width, chalky rice percentage, whiteness degree, 1000 grain weight, brown rice rate, taste meter value, peak viscosity, trough viscosity, breakdown viscosity and final viscosity significantly decreased while grain length width ratio, head rice rate, alkali digestion value, protein content and setback viscosity markedly increased under cold water irrigation. However, the other traits such as grain length, amylose content, milled rice rate, time reaching peak viscosity and pasting temperature were not significantly affected by cold water irrigation. Significant correlation relationships were discovered between phenotypic acceptability and cold response index of taste meter value, protein content, peak viscosity and breakdown viscosity. Therefore it would be very important to improve the cold tolerance of Yunnan varieties in order to stabilize and improve their eating quality.