Influence of drought stress on pistil physiology and reproductive success of two Gossypium hirsutum cultivars differing in drought tolerance
Influence of drought stress on pistil physiology and reproductive success of two Gossypium hirsutum cultivars differing in drought tolerance
复制标题
干旱胁迫对两个耐旱性不同的陆地棉品种雌蕊生理和繁殖成功率的影响
DOI：
10.1111/ppl.13030
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发表时间：
2020
影响因子：
6.4
通讯作者：
Zhou Zhiguo
中科院分区：
文献类型：
--
作者：
Hu Wei;Huang Yanjun;Bai Hua;Liu Yu;Wang Shanshan;Zhou Zhiguo
干旱胁迫下生殖失败的原因知之甚少。我们推测，生殖失败与干旱诱导的雌蕊生物化学变化有关。为了解决这一假设，用两个棉花品种（德夏棉1号，耐旱;豫早棉9110，干旱敏感）进行了水分亏缺诱导实验。结果表明，DS降低了两个品种对生叶的光合作用，并下调了雌蕊蔗糖转运蛋白基因（GhSUT-1）的表达，导致雌蕊碳积累减少，这反映在淀粉积累减少上。干旱胁迫下，雌蕊中作为势能的淀粉和作为直接能的三磷酸腺苷（ATP）含量降低，表明花粉管进入胚珠所需的能量减少，受精胚珠数减少，受精效率降低。此外，尽管雌蕊过氧化物酶活性在DS下增加，但在干旱雌蕊中测得的过氧化氢（H2 O2）水平仍然高于浇水良好的雌蕊，破坏生殖活动。DS对豫早棉9110光合速率、雌蕊GhSUT-1表达、碳积累、淀粉和ATP含量的影响大于德夏棉1号，以及超氧化物歧化酶、过氧化氢酶活性、抗坏血酸和H2 O2含量对DS的不同反应可能是导致豫早棉9110施肥效率下降幅度大于德夏棉1号的原因。因此，干旱胁迫下胚珠受精率降低与干旱胁迫下雌蕊碳水化合物代谢紊乱和抗氧化防御能力降低有关，干旱胁迫对干旱敏感品种雌蕊碳水化合物代谢和抗氧化防御能力的影响比耐旱品种更显著。
The causes of reproductive failure under drought stress (DS) are poorly understood. We hypothesized that reproductive failure was related to drought‐induced changes in pistil biochemistry. To address this hypothesis, a water deficit‐induced experiment was conducted with two cotton cultivars (Dexiamian 1, drought tolerant; Yuzaomian 9110, drought sensitive). Results showed that DS decreased the photosynthesis of subtending leaf and downregulated sucrose transporter gene (GhSUT‐1) expression in pistil for both cultivars, resulting in lower pistil carbon accumulation which was reflected in the decreased starch accumulation. Lower starch, as potential energy, and adenosine triphosphate (ATP), as direct energy, in droughted pistils suggested less energy for pollen tube entrance into ovules, reducing the fertilized ovule number and fertilization efficiency. Further, although pistil peroxidase activity increased under DS, a higher hydrogen peroxide (H2O2) level still was measured in droughted pistils than well‐watered pistils, damaging reproductive activities. Moreover, larger decreases in photosynthesis, pistilGhSUT‐1expression, carbon accumulation, starch and ATP contents caused by DS for Yuzaomian 9110 than Dexiamian 1, and different responses of superoxide dismutase and catalase activities, and ascorbic acid and H2O2contents to DS between the two cultivars might be the reasons causing a greater decrease in fertilization efficiency for Yuzaomian 9110 than Dexiamian 1 under DS. Thus, we suggest that decreased ovule fertilization under DS was related to the disorganized carbohydrate metabolism and inefficient antioxidant defense in droughted pistils, and the effects of DS on pistil carbohydrate metabolism and antioxidant defense were more significant for drought‐sensitive cultivars than drought‐tolerant cultivars.