Abstract Heat stress compromises wheat resistance to Hessian fly (HF, Mayetiola destructor (Say)) (Diptera: Cecidomyiidae) infestation. The objective of this research is to analyze the molecular basis of heat-induced loss of wheat resistance to HF infestation using RNA Sequencing (RNA-seq). To this end, two resistant wheat cultivars ‘Molly' and ‘Caldwell’ containing the resistance genes H13 and H6, respectively, were infested with an avirulent HF biotype GP and treated with different temperatures to examine the impact of heat stress on their resistance phenotypes. Tissue samples collected from HF feeding sites in Molly plants were subjected to RNA-seq analysis to determine the effect of heat stress on transcript expression of genes in wheat plants. Our results indicate that resistance to HF infestation in Caldwell is more sensitive to heat stress than that in Molly, and that heat stress down-regulates most genes involved in primary metabolism and biosynthesis of lignin and cuticular wax, but up-regulate most or all genes involved in auxin and 12-oxo-phytodienoic acid (OPDA) signaling pathways. Our results and previous reports suggest that heat stress may impair the processes in wheat plants that produce and mobilize chemical resources needed for synthesizing defensive compounds, weaken cell wall and cuticle defense, decrease OPDA signaling, but increase auxin signaling, leading to the suppressed resistance and activation of susceptibility.

中文翻译：

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使用 RNA 测序分析热诱导小麦对 Hessian 蝇（双翅目：Cecidomyiidae）侵染的抗性损失的分子基础

摘要 热应激损害小麦对黑森蝇（HF，Mayetiola destructor (Say)）（双翅目：Cecidomyiidae）侵染的抵抗力。本研究的目的是使用 RNA 测序 (RNA-seq) 分析热诱导小麦对 HF 侵染抗性丧失的分子基础。为此，分别含有抗性基因 H13 和 H6 的两个抗性小麦品种“Molly”和“Caldwell”被无毒的 HF 生物型 GP 侵染，并用不同的温度处理以检查热应激对其抗性表型的影响。从 Molly 植物的 HF 取食部位收集的组织样本进行 RNA-seq 分析，以确定热应激对小麦植物基因转录表达的影响。我们的结果表明，Caldwell 对 HF 侵染的抗性比 Molly 对热应激更敏感，并且热应激下调了大多数参与木质素和角质层蜡的初级代谢和生物合成的基因，但上调了大部分或所有基因参与生长素和 12-氧代植物二烯酸 (OPDA) 信号通路。我们的研究结果和之前的报告表明，热应激可能会损害小麦植物生产和动员合成防御性化合物所需的化学资源的过程，削弱细胞壁和角质层防御，减少 OPDA 信号，但增加生长素信号，导致抗性和抗性受到抑制。敏感性的激活。但上调涉及生长素和 12-氧代-植物二烯酸 (OPDA) 信号通路的大部分或所有基因。我们的研究结果和之前的报告表明，热应激可能会损害小麦植物生产和动员合成防御性化合物所需的化学资源的过程，削弱细胞壁和角质层防御，减少 OPDA 信号，但增加生长素信号，导致抗性和抗性受到抑制。敏感性的激活。但上调涉及生长素和 12-氧代-植物二烯酸 (OPDA) 信号通路的大部分或所有基因。我们的研究结果和之前的报告表明，热应激可能会损害小麦植物生产和动员合成防御性化合物所需的化学资源的过程，削弱细胞壁和角质层防御，减少 OPDA 信号，但增加生长素信号，导致抗性和抗性受到抑制。敏感性的激活。