抽穗期高温胁迫对水稻产量构成要素和品质的影响

以扬稻6号与南粳43为试验材料,通过在人工气候箱中进行高温处理,研究抽穗期高温胁迫对水稻产量构成要素及稻米品质的影响,旨在深入探讨高温对水稻的伤害机理。研究表明:水稻抽穗期高温降低了水稻的每穗总粒数、结实率和千粒重,同时稻米的糙米率、精米率、整精米率、可溶性糖和蛋白质含量也呈下降趋势,而稻米的垩白率、垩白度和直链淀粉含量增加明显,随胁迫温度的提高和胁迫时间的延长,2个水稻品种的产量构成要素和稻米品质急剧下降。相同温度胁迫下,扬稻6号的热害指数(Index of heat sensitivity,HIS)稍低于南粳43,其中扬稻6号的产量构成要素和品质受高温的影响也稍低于南粳43,说明扬稻6号耐高温能力高于南粳43。研究结果为进一步了解高温对水稻结实和稻米品质的伤害机理,筛选耐热性强的水稻品种提供重要的理论依据。

Effects of High Temperature Stress on Yield Components and Grain Quality during Heading Stage

The effects of high temperature stress on yield components and grain quality of japonica rice Yangdao 6 and japonica rice Nanjing 43 in plant growth chamber with two temperature treatments during heading stage were studied.The results showed that brown rice rate,milled rice rate,head rice rate,number of grains per panicles,seed setting rate,kernel weight,soluble sugar content and protein content in two rice varieties were lower,chalkiness rate and chalkiness degree were higher.Moreover,the damage on yield components and grain quality in two rice varieties were more serious with elevation of stress temperature and elongation of stress time.Index of heat sensitivity（HIS） and the damage degree for Nanjing 43 was higher than that for Yangdao 6 under the same high temperature stress.So the capacity of high temperature tolerance of Yangdao 6 was higher than Nanjing 43.The results could provide important theoretical evidence for revealing the damage mechanism on yield components and grain quality,selecting stronger heat tolerance of rice cultivar.