Abstract

High temperature stress is an inevitable environmental factor in certain geographical regions. To study the effect of day and night high temperature stress on male reproduction, the heat-sensitive cotton line H05 was subjected to high temperature stress. High day/normal night (HN) and normal day/high night (NH) temperature treatments were compared with normal day/normal night (NN) temperature as a control. At the anther dehiscence stage, significant differences were observed, with a reduction in flower size and filament length, and sterility in pollen, seen in NH more than in HN. A total of 36 806 differentially expressed genes were screened, which were mainly associated with fatty acid and jasmonic acid (JA) metabolic pathways. Fatty acid and JA contents were reduced more in NH than HN. Under NH, ACYL-COA OXIDASE 2 (ACO2), a JA biosynthesis gene, was down-regulated. Interestingly, aco2 CRISPR-Cas9 mutants showed male sterility under the NN condition. The exogenous application of methyl jasmonate to early-stage buds of mutants rescued the sterile pollen and indehiscent anther phenotypes at the late stage. These data show that high temperature at night may affect fatty acid and JA metabolism in anthers by suppressing GhACO2 and generate male sterility more strongly than high day temperature.

中文翻译：

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日/夜高温可明显破坏脂肪酸和茉莉酸的代谢，从而导致男性不育。

摘要

在某些地理区域中，高温胁迫是不可避免的环境因素。为了研究昼夜高温胁迫对雄性生殖的影响，对热敏棉株H05进行了高温胁迫。将高温/正常夜晚（HN）和正常白天/夜晚（NH）温度处理与正常白天/正常夜晚（NN）温度进行比较。在花药开裂阶段，观察到显着差异，其中花的大小和花丝长度减少，花粉不育，在NH中比在HN中更多。筛选了总共36 806个差异表达基因，这些基因主要与脂肪酸和茉莉酸（JA）代谢途径有关。NH中的脂肪酸和JA含量比HN降低更多。在NH下，酰基-COA氧化酶2JA生物合成基因（ACO2）被下调。有趣的是，aco2 CRISPR-Cas9突变体在NN条件下显示出雄性不育。茉莉酸甲酯在突变体早期芽中的外源应用挽救了后期的不育花粉和不裂裂的花药表型。这些数据表明，夜间高温可能通过抑制GhACO2来影响花药中的脂肪酸和JA代谢，并且比白天高温更强烈地产生雄性不育。