Tea plants [Camellia sinensis (L.) O. Kuntze] are hyperaccumulators of fluoride (F), but excessive F will harm the photosynthesis and metabolic activities of tea plants. Potassium (K) is one of the essential macronutrients of tea plants, which can enhance the photosynthesis of tea plants and their stress resistance. However, there are fewer studies on K in the accumulation of F in tea plants. In this study, we set three K treatment concentrations of 0 mM, 5 mM, 10 mM and finally found that when the tea plants were treated with F, exogenously applied 5 mM K treatment increased chlorophyll content, photosynthesis, and antioxidant enzyme activity, and reduced the extent of cellular damage, where starch particles content was reduced and the interstices of the chloroplast grana layer were more compact. After K treatment, the F content of new shoots decreased, and the flow rate of absorption of K by roots under F treatment was significantly increased through the Non-invasive Micro-test Technology (NMT), and 5 mM K treatment could effectively stabilize the membrane potential of roots. In addition, after K treatment, the relative expression of the F exporter CsFEX in tea plants was significantly upregulated, while the stress resistance gene expression of CsHAKs in tea plants was downregulated. Above all, appropriate K application could effectively alleviate the hyperaccumulation and stress effects of F on tea plants.

茶树[Camellia sinensis (L.) O. Kuntze]是氟化物（F）的超富集植物，但过量的F会损害茶树的光合作用和代谢活动。钾（K）是茶树必需的大量营养素之一，可以增强茶树的光合作用和抗逆性。但有关茶树F积累中K的研究较少。在本研究中，我们设定了0 mM、5 mM、10 mM 3个K处理浓度，最终发现当茶树用F处理时，外源施加5 mM K处理增加了叶绿素含量、光合作用和抗氧化酶活性，并且减少了细胞损伤的程度，淀粉颗粒含量减少，叶绿体基粒层的间隙更加紧凑。 K处理后，新芽的F含量下降，通过非侵入性微测试技术（NMT）显着提高了F处理下根系吸收K的流量，并且5 mM K处理可以有效稳定F处理下的K。根的膜电位。此外，K处理后，茶树中F输出蛋白CsFEX的相对表达量显着上调，而茶树抗逆基因CsHAKs的表达量则下调。最重要的是，适当的钾肥施用可以有效减轻氟对茶树的超积累和胁迫影响。