全球变暖严重威胁植物生长,并可能导致产量下降。尽管研究结果表明类黄酮在植物的生物过程中起着重要的作用,它们对金线莲热应激的反应(Wall。)林德尔。尚不清楚。这里,我们旨在研究刺梨在热应激下的黄酮类成分,并评估外源施用槲皮素对热应激耐受性的影响。代谢组分析表明槲皮素,tricetin,异鼠李素,scutellarein,和4\',7-异黄酮二醇是刺梨的主要上调类黄酮,基于投影中的变量重要性>1且倍数变化>2。使用标准曲线测定黄酮类化合物的浓度表明,槲皮素,山奈酚,异鼠李素含量增加了8.24-,7.55-,和5.01倍,分别,在热应力期间,而芦丁浓度从83.04降至80.89mg/kg(干重)。此外,转录组分析表明黄酮类生物合成途径中几个基因的表达增加,包括苯丙氨酸解氨酶和查尔酮合成酶。此外,槲皮素的外源施用提高了抗氧化能力和生理参数,包括光合速率和叶绿素含量,热应激下的刺梨。总的来说,根据整合的代谢组学,转录组,和生化分析,为提高刺梨的生物学价值提供新的见解。
Global warming severely threatens plant growth, and could lead to yield reduction. Although findings suggest that flavonoids play important roles in biological process in plants, their response to heat stress in Anoectochilus roxburghii (Wall.) Lindl. remains unclear. Here, we aimed to examine the flavonoid profile of A. roxburghii under heat stress and assess the effect of exogenous application of quercetin on heat stress tolerance. Metabolome analysis showed that quercetin, tricetin, isorhamnetin, scutellarein, and 4\',7-Isoflavandiol were the main upregulated flavonoids in A. roxburghii, based on variable importance in the projection >1 and with fold change >2. Determination of the concentrations of the flavonoids using a standard curve revealed that quercetin, kaempferol, and isorhamnetin contents increased by 8.24-, 7.55-, and 5.01-fold, respectively, during heat stress, whereas rutin concentration decreased from 83.04 to 80.89 mg/kg (dry weight). Additionally, transcriptome analysis indicated increased expression of several genes in flavonoid biosynthesis pathways, including phenylalanine ammonia-lyase and chalcone synthase. Moreover, exogenous application of quercetin improved the antioxidant capacity and physiological parameters, including photosynthetic rate and chlorophyll content, of A. roxburghii under heat stress. Overall, the flavonoid profile of A. roxburghii under short-term heat stress was characterized based on integrated metabolomic, transcriptomic, and biochemical analyses, providing new insights for improving the biological value of A. roxburghii.