Key Laboratory of Tea Science of Ministry of Education, Hunan Agricultural University, Changsha 410128, China.
National Research Center of Engineering & Technology for Utilization of Functional Ingredients from Botanicals, Collaborative Innovation Center of Utilization of Functional Ingredients from Botanicals and Co-Innovation Center of Education Ministry for Utilization of Botanical Functional Ingredients, Hunan Agricultural University, Changsha 410128, China.
Int J Mol Sci. 2024 Mar 29;25(7):3817. doi: 10.3390/ijms25073817.
Extreme drought weather has occurred frequently in recent years, resulting in serious yield loss in tea plantations. The study of drought in tea plantations is becoming more and more intensive, but there are fewer studies on drought-resistant measures applied in actual production. Therefore, in this study, we investigated the effect of exogenous tea polyphenols on the drought resistance of tea plant by pouring 100 mg·L of exogenous tea polyphenols into the root under drought. The exogenous tea polyphenols were able to promote the closure of stomata and reduce water loss from leaves under drought stress. Drought-induced malondialdehyde (MDA) accumulation in tea leaves and roots was also significantly reduced by exogenous tea polyphenols. Combined transcriptomic and metabolomic analyses showed that exogenous tea polyphenols regulated the abnormal responses of photosynthetic and energy metabolism in leaves under drought conditions and alleviated sphingolipid metabolism, arginine metabolism, and glutathione metabolism in the root system, which enhanced the drought resistance of tea seedlings. Exogenous tea polyphenols induced jasmonic acid-isoleucine (JA-ILE) accumulation in the root system, and the jasmonic acid-isoleucine synthetase gene (TEA028623), jasmonic acid ZIM structural domain proteins (JAMs) synthesis genes (novel.22237, TEA001821), and the transcription factor MYC2 (TEA014288, TEA005840) were significantly up-regulated. Meanwhile, the flavonoid metabolic flow was significantly altered in the root; for example, the content of EGCG, ECG, and EGC was significantly increased. Thus, exogenous tea polyphenols enhance the drought resistance of tea plants through multiple pathways.
近年来极端干旱天气频繁发生，导致茶园产量严重损失。对茶园干旱的研究越来越深入，但实际生产中应用的抗旱措施研究较少。因此，本研究通过向干旱条件下茶树根部浇灌 100mg·L 的外源茶多酚，研究了外源茶多酚对茶树抗旱性的影响。结果表明，外源茶多酚能够促进茶树在干旱胁迫下关闭气孔，减少叶片水分损失。外源茶多酚还能显著降低干旱胁迫下茶树叶片和根系中丙二醛（MDA）的积累。转录组和代谢组联合分析表明，外源茶多酚调节了茶树叶片在干旱条件下光合作用和能量代谢的异常响应，并缓解了根系中的鞘脂代谢、精氨酸代谢和谷胱甘肽代谢，增强了茶树幼苗的抗旱性。外源茶多酚诱导茶树根系中茉莉酸异亮氨酸（JA-ILE）的积累，茉莉酸异亮氨酸合成酶基因（TEA028623）、茉莉酸 ZIM 结构域蛋白（JAMs）合成基因（novel.22237、TEA001821）和转录因子 MYC2（TEA014288、TEA005840）显著上调。同时，根系中类黄酮代谢流也发生了明显改变，例如 EGCG、ECG 和 EGC 的含量显著增加。因此，外源茶多酚通过多种途径增强茶树的抗旱性。
