Decrease of Leaf Water Potential and Leaf Injury of Tea Plant (Thea sinensis L.) Subject to Cold Winter Wind in Sanin Region of Japan : I. Response of leaf water potential and leaf injury under field conditions

Japanese Journal of Crop Science

Akira FUKUDA¹  Tadashi IMAKI¹  Satoshi YAMATANI¹  Tohru KOBATA¹ 

关键词: Cold wind injury;    寒風による被害;    Leaf water potential;    強風;    Low temperature;    チャ;    Strong wind;    低温;    Tea.;    水ポテンシャル;   

DOI  :  10.1626/jcs.62.188

学科分类：农业科学（综合）

来源: Nihon Sakumotsu Gakkai / Crop Science Society of Japan

【 摘 要 】

Tea leaf sometimes receives serious damage as leaf blight or defoliation by winter cold wind in Sanin region of Japan. When wind of 4-7ms-1 blew, air temperature decreased to 0∼-4.4°C and a little snow remained on the ground, leaf water potential (ΨL) of tea plant (cv. Yabukita) was lowered to -1.2MPa in mid night and decreased to -2.3MPa in daytime of the next day. Leaf blight appeared one or two days after the condition. This temperature is a little higher than that causing freeze damage of tea leaves. However, when wind speed was lower that, air temperature was near 3-5°C and there was no snow, ΨL decreased only to -1.0MPa and leaf injury was not observed. ΨL did not decrease under -1.1MPa even in a hot summer day. We observed relationships between pressure rate and leaf injury of tea leaves pressurized with a pressure chamber in order to make analogous comparisons with decreases of ΨL by the cold winter wind. Leaf death started from pressurized rate 1.0MPa and 1.8MPa in winter and summer tea leaves, respectively, and the death was urged by more increase of pressurization rate. We suggested that the cold wind injury is caused by water deficiency of tea leaf as indicated by decrease of ΨL under the strong cold wind and low temperature condition, and, in particular, winter tea leaves more easily receive damage because winter leaves are sensitive to decrease of ΨL more than other seasons leaves.

【 授权许可】

Unknown