Evaluation of Ammonium Nitrogen and Nitrate on the Tea Plant as Nitrogen Source (Part 1)

The evaluation of NH4-N and NO3-N as nitrogen source on the tea plant which supplied in media containning 25, 50, 100 ppm. of nitrogen respectively was investigated from 1963 to 1964 by sand culture method. The results obtained were summarized as follows.1. Generally, the tea plant supplied with NH4-N showed better growth than that with NO3-N. The growth of the tea plant increased according to the amount of nitrogen sources in the first year, but that decreased in high concentration next year.2. Nitrogen content in the tea plant supplied with NH4-N was higher than that with NO3-N, and increased both according to the amount of nitrogen.3. Potassium content of the tea plant cultured with NH4-N showed lower than that with NO3-N. Calcium content of the tea plant in NH4-N plot decreased according to the amount of nitrogen. Magnecium content of the tea plant cultured with both nitrogen sources decreased according to the amount of nitrogen.4. Polyphenol oxidase activity and catalase activity of the tea leaves cultured with NH4-N showed higher than that with NO3-N.5. There was general tendency that assimilative power and respiratory activity of the tea leaves cultured with NH4-N showed higher levels than that with NO3-N.6. Chlorophyll content of the tea leaves cultured with NH4-N was more than that with NO3-N.7. Tannin content of the tea leaves cultured with NH4-N showed higher than that with NO3-N. And tannin content of the tea leaves increased according to the amount of NH4-N but decreased by NO3-N.