AUTHOR=Liu Mei-Ya , Tang Dandan , Shi Yuanzhi , Ma Lifeng , Zhang Qunfeng , Ruan Jianyun 

TITLE=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

JOURNAL=Frontiers in Plant Science

VOLUME=Volume 12 - 2021

YEAR=2021

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2021.753086

DOI=10.3389/fpls.2021.753086

ISSN=1664-462X

ABSTRACT=Over 30% of the Chinese tea plantation is supplied excess fertilizer, especially for nitrogen (N) fertilizer. Whether foliar N application on tea plants at dormancy stage could improve the quality of spring tea and be a complementary strategy to reduce the soil fertilization level remains unclear. In this study, 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 twice foliar N application of amino acid liquid fertilizer at winter dormancy stage was enough to significantly increase the N concentration of mature leaves and improved the quality of spring tea. Twice foliar application of 2% urea or liquid amino acid fertilizer at winter dormancy stage and twice at spring dormancy stage showed the best performance in tea plants among other foliar N fertilization methods, as it reduced the soil fertilization level in tea plantations without decreasing the total N concentration of mature leaves or deteriorating the quality of spring tea. Therefore, foliar N application on tea plant at its dormancy stage increases the N concentration of mature leaves, improves the quality and yield of spring tea and could be a complementary strategy to reduce soil fertilization level.