Foliar N Application on Tea Plant at Its Dormancy Stage Increases the N Concentration of Mature Leaves and Improves the Quality and Yield of Spring Tea

Mei-Ya Liu; Dandan Tang; Yuanzhi Shi; Lifeng Ma; Qunfeng Zhang; Jianyun Ruan

doi:10.3389/fpls.2021.753086

Foliar N Application on Tea Plant at Its Dormancy Stage Increases the N Concentration of Mature Leaves and Improves the Quality and Yield of Spring Tea

Front Plant Sci. 2021 Oct 15:12:753086. doi: 10.3389/fpls.2021.753086. eCollection 2021.

Authors

Mei-Ya Liu^{1

2}, Dandan Tang^{1

2}, Yuanzhi Shi^{1

2}, Lifeng Ma^{1

2}, Qunfeng Zhang^{1

2}, Jianyun Ruan^{1

2}

Affiliations

¹ Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou, China.
² Key Laboratory of Tea Plant Biology and Resources Utilization (Ministry of Agriculture and Rural Affairs), Hangzhou, China.

Abstract

Over 30% of the Chinese tea plantation is supplied with excess fertilizer, especially nitrogen (N) fertilizer. Whether or not foliar N application on tea plants at the dormancy stage could improve the quality of spring tea and be a complementary strategy to reduce soil fertilization level remains unclear. In this study, the effects of foliar N application on tea plants were investigated by testing the types of fertilizers and their application times, and by applying foliar N under a reduced soil fertilization level using field and ¹⁵N-labeling pot experiments. Results showed that the foliar N application of amino acid liquid fertilizer two times at the winter dormancy stage was enough to significantly increase the N concentration of the mature leaves and improved the quality of spring tea. The foliar application of 2% urea or liquid amino acid fertilizer two times at the winter dormancy stage and two times at the spring dormancy stage showed the best performance in tea plants among the other foliar N fertilization methods, as it reduced the soil fertilization levels in tea plantations without decreasing the total N concentration of the mature leaves or deteriorating the quality of spring tea. Therefore, foliar N application on tea plants at its dormancy stage increases the N concentration of the mature leaves, improves the quality and yield of spring tea, and could be a complementary strategy to reduce soil fertilization levels.

Keywords: amino acid; dormancy stage; foliar N application; polyphenol; tea plant; total N.