水稻耐高温逼熟的生理机制及育种应用研究初报  

Preliminary Studies on the Physiological Mechanism and the Breeding of High Tolerance of Heat-forced Maturity in Rice

作　　者：黄英金[1] 张宏玉[1] 郭进耀[1] 漆映雪[1] 彭耀东[1] 李长生[1] 刘宜柏[1] 徐正进[2] 

机构地区：[1]江西农业大学农学院,南昌330045 [2]沈阳农业大学稻作室,沈阳110161

出　　处：《科学技术与工程》2004年第8期655-658,共4页Science Technology and Engineering

基　　金：国家自然科学基金(30160041);国家科技部(99-022-03)育种专项的部分资助

摘　　要：水稻灌浆期耐热性的研究具有十分重要的理论与实践价值。研究结果表明,不同品种的耐热性存在极显著的遗传差异,以垩白米率、垩白大小、垩白度、秕粒率、受精粒重、饱粒重、籽粒充实度、饱粒密度等8项性状的耐热指数为指标,应用主成分分析法将其综合成3个彼此不相关的综合指标,再运用隶属函数值法求出每一品种耐热性的综合评价值,可较为全面、准确地对各品种的耐热性进行综合评价。耐热性强的品种高温胁迫后,剑叶的光合速率下降幅度明显较小,胁迫解除后恢复的程度也更高,叶绿素含量、RuBPc活性及内源多胺含量的变化趋势与光合速率相一致,是水稻耐高温逼熟的重要生理特征。高温胁迫导致水稻叶片叶绿素含量降低,表现出明显的降解作用,存在一个活性氧的伤害机理。50℃热致死时间所表示的细胞膜热稳定性可作为今后水稻灌浆期耐热性育种中适合单株选择鉴定的简便、准确的生理指标。采用生理育种途径,已育成了3个耐高温逼熟的优质、高产早籼稻新品种。The study on heat tolerance at grain-filling stage in rice has a very significant value on theory and practice. The results showed that there was much significant genetic diversity in heat tolerance among different varieties, according to the comprehensive evaluation on the heat tolerance of every variety by u-sing the subordinate function value. The eight heat tolerance indexes are as follows, rate of chalkiness rice, size of chalkiness, degree of chalkiness, unfilled grain rate, fertilized grain weight, filled grain weight, grain plumpness, density of filled grain, could be integrated as three irrelevant indexes by using principal component analysis, which could be evaluated more comprehensively and accurately at grain-filling stage in rice. The important physiological characteristic of heat tolerance of heat-forced maturity in rice is following: while the heat tolerance varieties are under heat stress, the decrease extent of photosynthesis rate of flag leaf is obviously lower; while releasing stress, the recovery level is also higher. The changing trend of chlorophyll content, RuBPc activity and endogenous polyamine content is consistent with that of photosynthesis rate. The high temperature stress makes the chlorophyll content of the rice leaf reduce, which demonstrates significant degradation effect, and exists a mechanism of the active oxygen damage. The cell membrane thermostability expressed by the heat killing time at 50℃ could be used as an accurate and handy physiological index for rice breeding for heat tolerance fitting individual-plant selection and identification at grain-filling stage in the future. Employing physiological breeding, It have bred three new early Hsien rice varieties of superior quality, high yield and high tolerance of heat-forced maturity.

关 键 词：水稻 灌浆期耐热性 生理机制 耐热性育种 叶绿素 选育 

分 类 号：S511[农业科学—作物学] S332.5