灌浆初期高温对水稻籽粒充实和剑叶理化特性的影响  

Effects of High Temperature on Grain-Filling of Rice Caryopsis and Physi-ological and Biochemical Characteristic of Flag Leave at Early Milky Stage

作　　者：廖江林[1] 肖小军[1,2] 宋宇[1] 周庆红[1] 黄英金[1] 

机构地区：[1]江西农业大学,作物生理生态与遗传育种教育部重点实验室,南昌330045 [2]江西省红壤研究所,南昌331717

出　　处：《植物生理学报》2013年第2期175-180,共6页Plant Physiology Journal

基　　金：江西省主要学科带头人项目(70004);江西省自然科学基金项目(2007GZN0253)

摘　　要：为探明灌浆初期高温热害降低水稻籽粒充实度的可能生理原因,以遗传背景相近而灌浆期耐热性存在显著差异的耐热水稻纯系XN0437T和热敏感水稻纯系XN0437S为材料,于水稻抽穗后第10天进行高温处理,调查了水稻籽粒充实度,测定了与水稻剑叶光合效率、细胞膜透性和渗透调节有关的生理指标。结果表明,高温处理后水稻籽粒充实度下降,剑叶的叶绿素含量、净光合速率和可溶性糖含量降低,热敏感纯系的下降幅度大于耐热纯系;剑叶的超氧化物歧化酶(SOD)活性、细胞膜透性、丙二醛(MDA)和脯氨酸含量增加,其中热敏感纯系的MDA含量和细胞膜透性增加幅度大于耐热纯系,而SOD活性和脯氨酸含量的增加幅度小于耐热纯系。说明灌浆初期高温抑制水稻剑叶光合效率,增加细胞膜透性和改变细胞内环境是高温热害降低水稻籽粒充实度的生理原因。To ascertain possible physiological causes of high temperature decreasing grain-filling rate at early milky stage of rice, two rice inbred lines, named XN0437T （heat-tolerant） and XN0437S （heat-sensitive）, were selected and treated by high temperature at the 10th day after heading. The grain plumpness, indexes related to photosynthetic efficiency, cell membrane permeability and osmotic adjustment in flag leaves were detected in rice lines XN0437T and XN0437S. The result showed that the grain plumpness was reduced under high temperature in both XN0437T and XN0437S and the reduced range of heat-sensitive line was greater than that of heat-tolerant line. The net photosynthetic rate, chlorophyll content and soluble sugar content were decreased in comparison with control both in heat-sensitive and heat-tolerant rice lines, and the decrease range of these physiological matter contents in heat-sensitive line were greater than that in heat-tolerant line. The superoxide dismutase （SOD） activity, malondialdehyde （MDA） content, cell membrane permeability and proline content were increased under high temperature, and the increased ranges of MDA content and membrane permeability in heat-sensitive line were higher than that in heat-tolerant line, while the increased ranges of SOD activity and proline content in heat-sensitive line were less than that in heat-tolerant line. The present study suggested that decreasing the photosynthetic efficiency of flag leaves, damaging the structure and function of cell membrane, and result in the intracellular environment altering were the physiological causes of high temperature at early milky stage limiting the grain plumpness of rice.

关 键 词：水稻 高温 籽粒充实度 理化特性 

分 类 号：S511[农业科学—作物学]