灌浆期高温对水稻光合特性、内源激素和稻米品质的影响  

Effects of high temperature on photosynthesis characteristics,phytohormones and grain quality during filling-periods in rice

作　　者：滕中华[1] 智丽[2] 吕俊[1] 宗学凤[1] 王三根[1] 何光华[1] 

机构地区：[1]西南大学农学与生物科技学院,重庆400716 [2]西南大学园艺园林学院,重庆400716

出　　处：《生态学报》2010年第23期6504-6511,共8页Acta Ecologica Sinica

基　　金：重庆市自然科学基金重点项目(2009BA1006);重庆市水稻玉米良种创新重大专项(CSTC;2007AB1033;2007AA1019);西南大学博士基金项目(SWU110002)

摘　　要：以2个籼稻品种:温度钝感型品种K30和温度敏感型品种R21为材料,利用人工气候室控温,在水稻灌浆期设置高温(日均温度34.9℃)和适温(日均温度28.0℃)处理,测定不同灌浆时期(5,10,15,20,25d和30d)光合特性、内源激素含量及稻米品质的变化。结果表明,高温增强了K30的光合能力,K30高温处理净光合速率(Pn)在整个灌浆期都明显高于对照;R21在灌浆前期(5、10d和15d)高温处理与适温处理Pn差异不明显,在灌浆后期(20、25d和30d)高温处理Pn下降。高温增加了K30叶片和籽粒脱落酸(ABA)含量;而R21高温处理和适温处理叶片与籽粒ABA含量的对比不明显。高温处理对两个水稻品种叶片和籽粒赤霉素(GA3)与生长素(IAA)含量也有不同程度影响。高温胁迫降低稻米品质,但K30比R21表现出更强的温度钝感特性。Rice is one of the most important food crops in the world.In recent years,extremely and constantly high temperature often appears in many parts of China in summer,and it leads to high frequency of the heat injury in rice.The hazard of high temperature is serious to the forming of grain quality in rice filling-period.To reveal the physiological adaptation mechanism of high temperature stress in rice,two rice cultivars（Oryza sativa L.indica）,K30-insensitive to high temperature,and R21-sensitive to high temperature,were treated with high temperature 34.9℃ and normal temperature 28.0℃ in artificial climate chamber,and the photosynthesis,endogenous phytohormones and grain quality were measured during grain-filling period at 5 d,10 d,15 d,20 d,25 d and 30 d.The results showed that the net photosynthesis rate（Pn） of K30 increased during whole grain-filling period under high temperature stress,whereas Pn of R21 changed little during early stage of filling period（5 d,10 d and 15 d） and dropped during late stage（20 d,25 d and 30 d）.High temperature stress intensified the falling speed of Pn of R21 in late stage of filling-period.Stomatal conductance（Gs）,transpiration rate（Tr） and CO2 concentration in middle lamella（Ci） also increased in the two cultivars during whole filling-periods under high temperature stress.The drop of Pn was related to non-stomatic factors.Leaf and grain abscisic acid（ABA） content of K30 increased,whereas ABA content of R21 changed little during grain-filling period.Gibberellins（GA3） and indoleacetic acid（IAA） contents were also affected by high temperature stress to some degree.High temperature increased leaf GA3 content of K30 and decreased grain GA3 content.The proportion of GA3 distribution in leaf and grain differed in two cultivars.Leaf and grain IAA contents of two cultivars decreased in late stage of filling-period.Grain IAA content of K30 changed little under high temperature,whereas IAA content of R21 ascended.For the two cultivars,the total starc

关 键 词：高温胁迫 水稻 光合特性 内源激素 稻米品质 

分 类 号：S511[农业科学—作物学]