水稻淀粉合成对夜温变化的响应  

Response of Rice Starch Synthesis to Night Temperature Changes

作　　者：张玉屏[1,2] 王军可 王亚梁 陈燕华 朱德峰 陈惠哲 向镜 张义凯 刘小军 朱艳[1] 曹卫星[1] ZHANG Yuping;WANG Junke;WANG Yaliang;CHEN Yanhua;ZHU Dengfeng;CHEN Huizhe;XIANG Jing;ZHANG Yikai;LIU Xiaojun;ZHU Yan;CAO Weixing(National Engineering and Technology Center for Information Agriculture/Jiangsu Key Laboratory for Information Agriculture,Nanjing Agricultural University,Nanjing 210095,China;China National Rice Research Institute/State Key Laboratory of Rice Biology,Hangzhou 310006,China)

机构地区：[1]南京农业大学国家信息农业工程技术中心/江苏省信息农业重点实验室,南京210095 [2]中国水稻研究所水稻生物学国家重点实验室,杭州310006

出　　处：《中国水稻科学》2020年第6期525-538,共14页Chinese Journal of Rice Science

基　　金：国家重点研发计划资助项目(2017YFD0300409);浙江省自然科学基金资助项目(LQ20C130009);现代农业产业技术体系建设专项(CARS-01-22)。

摘　　要：【目的】探究夜温变化对水稻淀粉形成的影响及其生理机制【方法】以优质软米浙禾香2号为材料,在灌浆初期设置31℃/20℃(LT)、31℃/24℃(NT)、31℃/28℃(HT)3个夜间温度模式,测定其直链淀粉和支链淀粉含量及合成关键酶活性及相关基因的表达。【结果】1)与NT相比,LT和HT处理显著降低粒重和淀粉积累,降低糊化温度和胶稠度,并影响支链淀粉链长,降低支链淀粉含量,提高直链淀粉含量,HT的影响要大于LT;2)LT和HT处理对白天叶片净光合速率的影响不显著,但显著降低籽粒中非结构性碳水化合物积累,抑制蔗糖转运基因Os SUT1、Os SUT2和Os SUT4在夜间和白天表达;3)LT和HT处理降低夜间和白天蔗糖水解相关酶活性,增加淀粉水解酶活性,导致可溶性糖含量升高,籽粒中糖利用受阻;4)与NT相比,LT和HT处理下腺苷二磷酸葡萄糖含量呈现白天降低而夜晚升高的趋势,腺苷二磷酸葡萄糖积累及利用受到抑制,颗粒结合淀粉合酶活性随处理时间延长而显著降低,且白天酶活性也受夜间温度的影响;5)与NT相比,LT和HT处理降低了夜间支链淀粉合成相关酶活性,抑制了夜间相关基因的表达,导致支链淀粉合成受阻,但对白天酶活及相关基因表达的影响不大。【结论】夜间高温对淀粉积累的影响要大于夜温降低,夜间高温/低温抑制全天蔗糖转运及代谢,进而抑制淀粉积累;支链淀粉合成受阻是导致直链淀粉相对含量升高的主要原因,直链淀粉合成相关酶活性(白天)受夜温变化影响,而支链淀粉合成相关酶活性(白天)受夜温变化的影响不显著。【Objective】To clarify the effect of night temperature changes on rice starch accumulation,and to explore circadian changes of physiological characteristics of rice amylose/amylopectin formation at various night temperatures.【Method】High-quality japonica rice‘Zhehexiang 2’was subjected to three night temperature gradients of 31℃/20℃(LT),31℃/24℃(NT),and 31℃/28℃(HT)at the beginning of grain ripening stage,and the amylose and amylopectin contents,the key enzyme activities involved in amylose and amylopectin formation and the expression of related genes were measured at noon and midnight.【Result】The results showed that 1)compared with NT,LT and HT treatments significantly reduced grain weight and starch accumulation,LT and HT both reduced amylopectin content and increased amylose content,meanwhile the effect of HT was greater than LT.LT and HT treatments decreased grain pasting temperature and gel consistency,and had a significant influence on branched chain length.2)The net photosynthetic rate of leaves under LT and HT presented no significant difference compared to NT,but LT and HT significantly reduced the accumulation of non-structural carbohydrates,meanwhile down-regulated the expression level of sucrose transporter genes OsSUT1,OsSUT2,and OsSUT4 both at noon and midnight.3)LT and HT treatment reduced sucrose hydrolysis-related enzyme activities,meanwhile promoted starch hydrolase activities,resulting in increased soluble sugar contents,sugar utilization in grain was blocked.4)Compared with NT,the adenosine diphosphate glucose content showed a downward tendency during the day and a rising trend at night under the treatment of LT and HT,which presented that the accumulation and utilization of adenosine diphosphate glucose were inhibited.And the granules bound starch synthetase activity were significantly reduced under LT and HT compared to NT with the prolongation of the treatment,and the enzyme activity at daytime was significantly influenced by temperature changing at night.5)Compared

关 键 词：水稻 夜温变化 淀粉积累 生理特性 昼夜差异 

分 类 号：Q948.112[生物学—植物学] S511.01[农业科学—作物学]