【摘要】 利用从密阳 2 3/通 88 7和密阳 2 3/TR2 2 183杂交组合F3 代选拔获得的水稻耐冷性强的系统群和弱的系统群以及 3个亲本品种 ,探讨了冷水胁迫对稻米品质特性的影响以及水稻耐冷性对稻米品质冷水反应的影响。研究结果表明 ,冷水胁迫使水稻糙米粒形变小 ,其中糙米粒长度、长宽比和千粒重比宽度和厚度更容易受到冷水胁迫的负面影响。冷水胁迫使稻米碱消值和蛋白质含量增加 ,而使稻米胶稠度、直链淀粉含量、最高粘度、冷胶粘度和崩解值下降。在水稻幼苗期对耐冷性进行选择 ,对糙米粒形并不产生显著影响。在自然条件下耐冷性强的和弱的2个系统群间品质特性未见显著差异 ,但在冷水胁迫下幼苗期耐冷性强或田间耐冷性强的系统群直链淀粉含量、最高粘度、热浆粘度、冷胶粘度显著高于幼苗期耐冷性弱或田间耐冷性弱的系统群 ,而蛋白质含量、消减值、崩解值和消减率则相反。认为耐冷性强的系统群的稻米品质比耐冷性弱的系统群表现出较迟钝的冷水反应 ,耐冷性对稻米品质的冷水反应产生一定影响。因此 ,提高水稻耐冷性对水稻品质的稳定和改善将产生积极的影响。更多还原

【Abstract】 Three rice varieties and several F 3 lines with high and low cold tolerance selected from F 3 segregation lines of two crosses Milyang23/Tong88-7 and Milyang23/ TR22183 were used to analyze effects of cold tolerance on the response of grain quality to cold water irrigation. Cold water irrigation resulted in the decrease of rice grain size. The length, length-width ratio and weight of brown rice grain were affected more sensitively by cold water irrigation than the width and thickness. The shape of brown rice grain was not significantly affected by the selection for cold tolerance at seedling stage. The gel consistency, amylose content, peak viscosity, cool viscosity, breakdown viscosity and consistency viscosity decreased, while alkali digestibility value and protein content increased by cold water irrigation. Under normal irrigation condition the physicochemical properties of milled rice and viscogram components of milled rice flour were not significantly different between lines with high and low cold tolerance. Under cold water irrigation the amylose content, peak viscosity, hot viscosity, final viscosity of rice lines with high cold tolerance at seedling stage or high field cold tole-rance were higher than those of rice lines with low cold tolerance, while the protein content, setback viscosity, breakdown ratio and setback ratio were lower than those of rice lines with low cold tolerance. These imply that the cold water response of rice grain quality was less sensitive in the lines with high cold tolerance than in the lines with low cold tole-rance, and the varietal improvement for cold tolerance would be important for grain quality improvement at the same time.更多还原