Evaluation of the Effects of Autumn and Spring Application of Nitrogen Fertilizer on the Growth and Some Nitrogen Constituents of the First Flush Shoots of Tea Plant

Abstract

Effects of autumn and spring nitrogen application on the growth and nitrogen constituents of first flush shoots were studied in tea plants grown in sand culture.
From the results of the analysis of variance, the growth of the shoots and the nitrogen accumulated in the shoots had statistically significant relationship with the nitrogen concentration applied in autumn and spring. The nitrogen which was remobilized from nitrogen applied in autumn correlated with the concentration of nitrogen in autumn with 1% significant level, and with the concentration of nitrogen in spring with 5% significant level. The concentration of amino acids in the shoots correlated with nitrogen concentration in autumn with 5% significant level, and with the concentration of nitrogen in spring with 1% significant level.
From the results of multiple regression analysis, partial regression coefficient of nitrogen concentration in autumn for the growth of the shoots was greater than that of the concentration of nitrogen in spring. The analysis of the accumulated nitrogen and the remobilized nitrogen showed the same results. But for the contents of amino acids in the shoots, the coefficient of the nitrogen con-centration in spring was markedly greater than that of the concentration of nitrogen in autumn.
These results suggested that the contribution of nitrogen applied in autumn for the growth of the shoots, accumulated nitrogen and remobilized nitrogen was markedly greater than that of the nitrogen applied in spring. On the other hand, nitrogen applied in spring was suggested to highly contribute to the concentration of amino acids in the shoots.