Effect of shading on the growth and quality of young leaves of five tea (Camellia sinensis L.) varieties of plants.

• Main Authors: Chung-Kuang Chen, 陳重光
• Other Authors: 王慶裕
• Format: Others
• Language: zh-TW
• Published: 2019
• Online Access: http://ndltd.ncl.edu.tw/cgi-bin/gs32/gsweb.cgi/login?o=dnclcdr&s=id=%22107NCHU5417006%22.&searchmode=basic

碩士 === 國立中興大學 === 農藝學系所 === 107 === Tea [Camellia sinensis (L.) O. Kuntze] plant, a perennial crop of the family Camellia (Theaceae), is a hobby crop which is also a special crop. In the past century, in order to pursue high-quality tea flush, tea farmers in Taiwan established their tea garden in middle and high altitudes, that might destroy soil and water conservation on the hillside. Therefore, we try to investigate the feasibility of planting tea plants under shading in the low-altitude land, and also study the growth of different varieties of tea plants, as well as the response of tea quality to light intensity. In this study, we used five varieties of tea plants including TTES No.8, TTES No.12 (Jinxuan), TTES No.18 (Hongyu), Shy Jih Chuen, and Chin-Shin Oolong. Sixty percent of shading in the greenhouse was performed. And we measured the changes of seedling growth and tea quality throughout the experiment. The results indicated that shading treatment significantly increased plant height, length of the representative branch, bud numbers of the representative branch, mature leaf number of the representative branch, and relative chlorophyll content of Qingxin Oolong. However, the agronomic traits of the Shy Jih Chuen were not affected by shading. It can be seen that the Chin-Shin Oolong is more sensitive to strong light, and the Shy Jih Chuen is insensitive. The shading can improve the growth potential of the Chin-Shin Oolong. In addition, according to the changes in the total polyphenols, total flavonoids, total anthocyanins, and total catechins in young tea leaves,it is shown that after one year of continuous shading, the total polyphenols and total catechins in the five varieties were significantly decreased. Also, the total polyphenols, total flavonoids and total catechins contents in the small-leaf Chin-Shin Oolong and large-leaf variety were significantly decreased, but total anthocyanins contents increased. The response to the light intensity between the large leaf variety and the small-leaf variety showed that there was no regular change in the chemical compositions of the tea leaves between the large and small-leaf tea varieties. If there is a suitable for shading under a high-light environment, it can promote the growth of tea plants and reduce the bitterness and astringency of the tea, and thus improve the quality of the tea.