土壤水分供给对不同水稻的产量构成及其淀粉品质的影响

RICE YIELD AND STARCH QUALITY OF TWO RICE VARIETIES UNDER DIFFERENT SOIL WATER SUPPLY LEVELS

在人工气候室和网室条件下,测定了4个水分处理下2个籼型水稻材料中9B和金早47的株产量和淀粉品质。结果表明,中9B在水分胁迫下株产量显著降低主要原因在于有效穗数显著减少,而金早47随水分胁迫加重株产量显著降低,原因是水稻穗型变小,总粒数和实粒数显著减小。在水分胁迫下,2个水稻品种在产量构成中的不同表现,反映了不同水稻品种对水分胁迫的基因型差异。在人工气候室与网室条件下,随着水分供应的逐渐减少,2个材料的稻米表观直链淀粉含量逐渐升高,淀粉粘滞性谱的最高粘度、热浆粘度、冷胶粘度和崩解值逐渐下降,消减值逐渐增加,而糊化温度和淀粉凝胶的质构没有受到显著影响。这些参数的变化,表明稻米的食味品质有所下降,但这些稻米可以用于其他用途,比如适合糖尿病患者食用。

Pot experiments were conducted to study the responses of two indica rice Zhong 9B and Jinzao 47,under four different levels of soil water supply at climatological chamber and greenhouse conditions.Two rice varieties responded differently to water stress.The yield decrease of Zhong 9B under two environmental treatments of 60% and 40% soil water content were mainly caused by the decrease of effective numbers of panicles.The yield of Jinzao 47 was also decreased under water stress,which was caused by smaller panicle of grains per panicle and seed setting rate.In addition the effects of water supply levels on the starch quality were investigated.Results showed that the amylose content and setback viscosity increased apparently,whereas the peak viscosity,hot paste viscosity,cool paste viscosity and breakdown viscosity decreased with the decline of the water supply levels.It seemed that different water supply levels had no effect on the pasting temperature and gel texture parameters.Although the starch quality parameters reported in this study showed that the eating quality of the cooked rice became poorer,the rice varieties could be used as other purposes,such as providing suitable food for diabetic patients.