【摘要】 以汕优 6 3和武香粳 9号为供试品种 ,研究了结实期土壤水分胁迫对水稻强、弱势粒稻米主要米质性状和淀粉粘滞谱特征的影响。结果表明 :(1)两品种强势粒和弱势粒达到最大粒重和最小垩白时的结实期处理土水势是相同的 ,均为 - 2 0kPa,在此土水势下 ,强势粒和弱势粒加工品质和蒸煮品质无显著变化 ,改善了营养品质 ,米质相对较优 ;(2 )当土水势降到 - 6 0kPa时 ,强势粒和弱势粒粒重、整精米率及弱势粒的直链淀粉含量显著降低 ,胶稠度变硬 ,食味变差 ,米质变劣 ;(3)土壤水分对同一穗上不同粒位籽粒米粉的RVA谱特性的影响因粒位的不同而不同 ,强势粒米粉RVA谱间差异较小 ,弱势粒米粉RVA谱水分处理间存在明显差异 ,RVA谱特征值变化因品种而异 ,当土水势降到 - 6 0kPa时 ,武香粳 9号弱势粒淀粉粘滞谱特征值发生明显变化 ;(4 )同一品种强势粒和弱势粒米质以及RVA谱特性存在明显差异 ,在土水势为 - 2 0kPa时 ,这种差异相对较小。更多还原

【Abstract】 With Shanyou 63 (an indica-type hybrid cultivar) and Wuxiangjing 9 (a conventional japonica cultivar) as materials, effects of soil water stress on the main characters of superior and inferior grains quality and the properties of RVA profile during grain-filling period were studied. The main results were as follows: (1) When the soil water potential (SWP) was at -20 kPa, the grain weight of superior and inferior kernel in two cultivars was at its most, and the chalkiness was at its least. There was no obvious change in the milling and cooking quality and the nutrient quality was improved. The trend of high quality was observed; (2) When the SWP declined to -60 kPa, the weight and head milled rice of superior grains (SG) and inferior grains (IG) and the amylose content of IG were decreased significantly, stiffer gel consistency, bad taste quality and low rice quality was found; (3) Effects of SWP on the RVA characteristics of the different grains in a panicle varied with the kernel position, there were no significant difference in the RVA profiles of SG, but the obvious difference for IG in two cultivars, and especially the visible changes when the SWP decreased to -60 kPa; (4) The obvious difference of rice quality and the character of RVA profile between SG and IG was found, which was relative small when the SWP was at -20 kPa.更多还原