Ecological Stoichiometric Characteristics of Leaf Elements in 40 Fujian Tea Tree Cultivars

Objective Assimilation of elements by 40 tea cultivars in Fujian in relation with ecology was analyzed.

Method The contents and stoichiometric ratios of C, N, P, and K in leaves of 40 varieties of tea plants in Fujian were determined for principal component and cluster analyses. Data obtained were evaluated based on 10 selected indicators including contents of C, N, P, and K and ratios of C/N, C/K, C/P, N/K, N/P, and P/K.

Result Aside from P, C/K, N/K, and P/K, all indicators on the contents of organic C and total N, P, and K as well as the stoichiometric ratios were found normally distributed in the tea leaves. Of the 40 tea varieties, 10 were N-limited with a N/P <14, and 25 P-limited with N/P >16. At the critical Euclidean distance of 17, the teas were clustered into 3 categories, i.e., the N-limited Group Ⅲ and the P-limited Group I and Group II that comprised 75% of the total. The top 3 principal indicators provided for 91.88% of the total variance explained. The top 6 tea varieties ranked in the order of Jinmudan > Daye-wulong> Chaoyang > Jinguanyin > Tieguanyin > Dahongpao, which agreed with the result base on the N and P contents.

Conclusion N, P, and N/P of tea leaves appeared to be the crucial indicators for the eco-stoichiometric evaluation in cultivating, selecting, and breeding teas.