Impact of Heat Stress on Expression of Wheat Genes Responsive to Hessian Fly Infestation

Abstract

Heat stress compromises wheat (Triticum aestivium) resistance to Hessian fly (HF, Mayetiola destructor (Say)). This study aimed to investigate the impact of heat stress on transcript expression of wheat genes associated with resistance to HF infestation under normal and heat-stressed conditions. To this end, ‘Molly’, a wheat cultivar containing the resistance gene H13, was subjected to HF infestation, heat stress, and the combination of HF infestation and heat stress. Our RNA-Seq approach identified 21 wheat genes regulated by HF infestation under normal temperatures (18 °C) and 155 genes regulated by HF infestation when plants were exposed to 35 °C for 6 h. Three differentially expressed genes (DEGs) from the RNA-Seq analysis were selected to validate the gene function of these DEGs using the RT-qPCR approach, indicating that these DEGs may differentially contribute to the expression of wheat resistance during the early stage of wheat–HF interaction under various stresses. Moreover, the jasmonate ZIM domain (JAZ) gene was also significantly upregulated under these treatments. Our results suggest that the genes in heat-stressed wheat plants are more responsive to HF infestation than those in plants growing under normal temperature conditions, and these genes in HF-infested wheat plants are more responsive to heat stress than those in plants without infestation.

Understanding and improving resistance to Hessian fly (Mayetiola destructor) in US wheat using genetic mapping and molecular techniques

“…In Yuan et al. (2022), Molly with H13 was used to examine the impact of heat stress on the regulation of genes associated with Hessian fly resistance. At a controlled temperature of 18 ° C, phenylalanine ammonia lyase genes, pathogenesis‐related protein 1 genes, and a chitinase IV precursor gene showed significant upregulation when the plants were infested with Hessian fly larvae.…”

“…These genes were not regulated by heat stress. Phenylalanine ammonia lyase is an important step in the pathway that leads to the synthesis of polyphenols including flavonoids, phenylpropanoids, and lignin (Yuan et al., 2022). These compounds play roles in antibiosis and cell wall strengthening, both of which are important components of plant defense.…”

“…These compounds play roles in antibiosis and cell wall strengthening, both of which are important components of plant defense. Pathogenesis‐related protein 1 genes are involved in the first step of plant defense against herbivores and pathogens (Yuan et al., 2022). Other genes important to resistance did show significant downregulation due to heat stress.…”

“…These included a carboxylesterase gene and aspartyl protease family protein gene, both of which are involved in the mobilization of lipids and proteins, and another phenylalanine ammonia lyase gene. This suggests that heat stress slows the ability of the plant to breakdown lipids and proteins needed for the resistance response as well as slowing the synthesis of necessary polyphenols (Yuan et al., 2022).…”

Advances in structure and function of auxin response factor in plants

“…In tomato, SlARF1 , ‐4 , ‐8A , ‐19 , and ‐ 24 bring about significant upregulation in alkalinity. In wheat, TaARF9 mediates the mechanism of alkali resistance and participates in oxidative stress (Yuan, 2016). In maize, there is significant upregulation of ZmARF1 under drought stress, suggesting that it may play an important role under drought stress (Sun et al, 2020).…”