College of Forestry, Guizhou University, Guiyang, Guizhou, China.
State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, China.
Plant Signal Behav. 2024 Dec 31;19(1):2359258. doi: 10.1080/15592324.2024.2359258. Epub 2024 Jun 3.
Tea plantations in Karst regions suffer from the serious effects of frequent temporary karst droughts, leading to a decline in tea production and quality in the region. The close relationship between growth and electrical parameters of plants, including physiological capacitance, resistance and impedance, can be used to accurately monitor their plant water status online, quickly, accurately, timely and nondestructively. In this study, three tea tree cultivars of Zhonghuang No.2 (ZH), Wuniuzao (WNZ), and Longjing 43 (LJ) with different levels of drought resistance were selected as experimental materials, and experiments were carried out under controlled conditions according to control (soil water content of 40-45%, D0), (keeping D0 no watering to 5 days, D5), (keeping D0 no watering to 10 days, D10), (the first day after D10 is rehydrated to D0 is regarded as R1) and (the fifth day after D10 rehydration to D0 is regarded as R5), to determine intracellular water metabolism and nutrient translocation characteristics based on intrinsic electrical parameters. The photosynthetic characteristics and chlorophyll fluorescence parameters were also determined to investigate the response of water metabolism to simulated karst drought in the three tea tree cultivars. The results indicated that the water metabolism patterns responded to environmental water changes with a medium water-holding capacity, medium water transport rate, and low water-use efficiency, and the nutrient patterns in those tea tree varieties demonstrated with a high nutrient flux per unit area, low nutrient transfer rate, and high nutrient transport capacity. After rehydration, only the electrical characteristics of WNZ returned to the D0 levels, but the net photosynthetic rate of all varieties returned to or even exceeded the D0 levels. The chlorophyll fluorescence parameters could not be used to characterize the recoverability of metabolism in tea trees. The electrical characteristics quickly reflected the response of the water metabolism in plants to environmental changes, and the fusion of electrical characteristics and photosynthetic characteristics was able to more quickly, accurately, and comprehensively reflect the response of water metabolism to temporary karst drought.
喀斯特地区茶园经常受到临时喀斯特干旱的严重影响，导致该地区茶叶产量和质量下降。植物生长与电参数（包括生理电容、电阻和阻抗）之间的密切关系可用于在线、快速、准确、及时和非破坏性地准确监测其植物水分状况。本研究选择了中黄 2 号（ZH）、乌牛早（WNZ）和龙井 43 号（LJ）三个抗旱性不同的茶树品种作为实验材料，在控制条件下进行实验，根据对照（土壤含水量为 40-45%，D0）、（保持 D0 不浇水至 5 天，D5）、（保持 D0 不浇水至 10 天，D10）、（D10 后第一天重新浇水至 D0 视为 R1）和（D10 后第五天重新浇水至 D0 视为 R5）进行实验，以确定基于固有电参数的细胞内水分代谢和养分转运特征。还测定了光合特性和叶绿素荧光参数，以研究水分代谢对三种茶树品种模拟喀斯特干旱的响应。结果表明，具有中等持水能力、中等水分运输率和低水分利用效率的水分代谢模式对环境水分变化做出响应，而这些茶树品种的养分模式表现为单位面积高养分通量、低养分转移率和高养分运输能力。再水合后，只有 WNZ 的电特性恢复到 D0 水平，但所有品种的净光合速率均恢复到甚至超过 D0 水平。叶绿素荧光参数不能用于表征茶树代谢的恢复能力。电特性可以快速反映植物水分代谢对环境变化的响应，电特性和光合特性的融合能够更快速、准确、全面地反映水分代谢对临时喀斯特干旱的响应。
