Effects of Low-Temperature Stress on Cold Resistance Biochemical Characteristics of Dali and Siqiu Tea Seedlings
Ming Chen,
Xizhe Zhu,
Mengyue Hou,
Wen Luo,
Yongwen Jiang,
Yaya Yu,
Jinjin Wang,
Haibo Yuan,
Xiaoxia Huang,
Jinjie Hua
Affiliations
Ming Chen
Southwest Landscape Architecture Engineering Research Center of National Forestry and Grassland Administration, College of Landscape Architecture and Horticulture Sciences, Southwest Forestry University, Kunming 650051, China
Xizhe Zhu
Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou 310008, China
Mengyue Hou
Southwest Landscape Architecture Engineering Research Center of National Forestry and Grassland Administration, College of Landscape Architecture and Horticulture Sciences, Southwest Forestry University, Kunming 650051, China
Wen Luo
Southwest Landscape Architecture Engineering Research Center of National Forestry and Grassland Administration, College of Landscape Architecture and Horticulture Sciences, Southwest Forestry University, Kunming 650051, China
Yongwen Jiang
Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou 310008, China
Yaya Yu
Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou 310008, China
Jinjin Wang
Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou 310008, China
Haibo Yuan
Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou 310008, China
Xiaoxia Huang
Southwest Landscape Architecture Engineering Research Center of National Forestry and Grassland Administration, College of Landscape Architecture and Horticulture Sciences, Southwest Forestry University, Kunming 650051, China
Jinjie Hua
Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou 310008, China
Cold stress causes considerable damage to tender tea seedlings. Previous studies have explored changes in the physiological and biochemical factors of tea in response to cold stress; however, the mechanisms of cold resistance in ancient tea tree plants are unclear. The aim of this study was to analyze the effects of 0 °C cold stress for 15 days and 24 °C ambient temperature recovery for 5 days on the physiological and biochemical characteristics of two representative old tea varieties: Dali tea and Siqiu tea. The results revealed significant changes in antioxidant, photosynthetic efficiency, and physiological and biochemical indicators in response to cold stress, with the two species exhibiting different patterns. Cold stress decreased chlorophyll and carotene content, Fv/Fm, Y(II), non-photochemical quenching coefficient, photochemical quenching, and superoxide dismutase (SOD) activity, and increased intercellular CO2 concentration and ascorbate peroxidase activity. Siqiu tea showed a higher increase in soluble sugar content and antioxidant enzyme activity and a lower accumulation of malondialdehyde and minimal fluorescence (F0) than Dali, indicating a greater tolerance to cold stress. Based on partial least-squares discriminant analysis, six key differential physiological indicators of cold resistance—water-soluble sugar, F0, peroxidase, catalase, SOD, and gas conductance—were identified. Our findings provide technical support for identifying ways to protect ancient tea trees from extreme weather conditions.
