小麦花后水分亏缺和复水对同化物转运和籽粒灌浆的影响  

Effect of Water Deficit and Rehydration on the Post-flowering Assimilate Transport and Grain Filling in Wheat

作　　者：杨丽丽 任建宏 刘溢建 殷俐娜[1,3] 邓西平[2,3] 王仕稳[1,3] YANG Lili;REN Jianhong;LIU Yijian;YIN Lina;DENG Xiping;WANG Shiwen(College of Resources and Environment, Northwest A&F University, Yangling, Shaanxi 712100, China;2College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, China;3State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Chinese Academy of Sciences and Ministry of Water Resources, Yangling, Shaanxi 712100, China)

机构地区：[1]西北农林科技大学资源环境学院,陕西杨陵712100 [2]西北农林科技大学生命科学学院,陕西杨陵712100 [3]中国科学院水利部水土保持研究所黄土高原土壤侵蚀与旱地农业国家重点实验室,陕西杨陵712100

出　　处：《西北植物学报》2020年第11期1909-1918,共10页Acta Botanica Boreali-Occidentalia Sinica

基　　金：国家自然科学基金(52079132)。

摘　　要：为了阐明水分亏缺对小麦花后同化物转运和籽粒灌浆的影响及其生理机制的相关变化,以盆栽小麦旱作品种‘长旱58’为材料,自花后9 d起,设置正常供水(WW)、中度干旱胁迫后复水(MD)和重度干旱胁迫后复水(SD)3个水分处理,比较干旱胁迫后复水处理对小麦籽粒产量、产量构成因素及水分利用效率、强弱势粒灌浆动态、旗叶光合性能、茎鞘非结构性碳水化合物(NSC)转运、籽粒形成关键酶活性变化等的影响。结果表明:(1)与WW相比,MD处理显著增加了小麦穗粒数和千粒重,进而提高籽粒产量、水分利用效率和小麦弱势粒的最大灌浆速率和平均灌浆速率,对强势粒则无显著影响,而SD处理则显著降低了穗粒数、千粒重、强弱势粒的最大灌浆速率和平均灌浆速率,但水分利用效率显著高于WW处理。(2)MD处理植株旗叶在小麦灌浆过程中维持了与WW基本相同的净光合速率,同时在小麦花后9~20 d时MD处理下气孔导度和蒸腾速率变化不明显,而在SD处理下气孔导度和蒸腾速率则急剧下降;另外,与WW相比,在整个灌浆期MD处理下旗叶叶绿素含量变化不显著,而SD处理下叶绿素含量呈大幅下降趋势。(3)MD处理提高了小麦弱势粒蔗糖合成酶和腺苷二磷酸葡萄糖焦磷酸化酶活性;同时使灌浆中后期有较高的果聚糖水解酶(FEH)活性和较低果聚糖含量,显著增强了茎鞘同化物质转运,提高茎鞘储藏物质对粒重的贡献率。研究发现,中度水分胁迫后复水处理小麦植株具有较好的叶片性能、花后较多的茎鞘同化物向籽粒转运以及较高的弱势粒库活性,从而提高旱作小麦弱势粒灌浆速率,增加穗粒数和粒重,进而提高籽粒产量。In order to clarify the effects of water deficit and rehydration on the assimilation transport and grain filling of wheat after anthesis,we applined three treatments,named,well water(WW),rehydration after moderate drought stress(MD)and rehydration after severe drought stress(SD),after 9 days flowering in pot experiment with wheat cultivar‘Changhan 58’.The yield,grain filling dynamics,photosynthetic performance of flag leaves,non-structural carbohydrate(NSC)transport in stem and sheath and the activities of key enzymes in grain,were investigated during the process of drought and rehydration.The results showed that:(1)compared with WW treatment,MD significantly increased the number of grains per spike and thousand-grain weight of wheat and thus improving the grain yield,water use efficiency and maximum grouting rate of grains and the average filling rate.For the SD treatment,grain numbers per spike,the superior and inferior spikelets of maximum grouting rate and the average filling rate were significantly decreased,but the water use efficiency was significantly increased compared with WW.(2)The photosynthetic rate of flag leaves during wheat filling had no difference between MD treatment and WW treatment.Meanwhile,compared with WW,stomatal conductance and transpiration rate at 9-20 d after wheat flowering were not changed under MD,while they were profoundly decreased under SD.(3)The activities of sucrose synthase and adenosine diphosphate glucose pyrophosphorylase in wheat was increased by MD treatment;Meanwhile,MD had lower fructose content,which suggested that contribution of substances in stem to the yield were increased.The study found that higher photosynthesis,more assimilates in the stem after anthesis transfer to the grain and higher sugar metabolism enzyme activity in the inferior spikelets,and the number of grains per spike and thousand-grain weight,then finally increase the physiological basis of yield.

关 键 词：小麦 水分亏缺 籽粒灌浆 强势粒 弱势粒 茎鞘物质运转 

分 类 号：Q945.78[生物学—植物学]