Effect of Supplied Dolomite in Tea Field on Absorption of Phosphorus by Tea Plant

The effect of supplied dolomite in tea field on absorption of phosphorus by tea plant was examined in field experiment (soil : "Kuroboku" derived from diruvial and tea variety: Yabuki ta) . Radioactive (32P) monocalcium phosphate (4.32mCi, P2O5 12g. per bush) was fertilized in three plots (0kg, 100kg. and 300kg. dolomite/10a.) on 30 th May 1967. The new leaves were cropped in 2nd season (21st June) and 3rd season (31st July). The radioactivity and the total phosphorus content of tea leaves were determined with ordinary method. The percentage of supplied phosphorus content to total phosphorus content was calculated. The available phosphorus content and the transformation of radio and nonradioactive phosphates in each soil were investigated. The results were summarized as follows : The yield of new leaves was most in 100kg./10a. dolomite plot and least in without dolomite plot. The phosphorus content of new leaves increased by fertilizing of dolomite in tea soil. Increasing amount of fertilized dolomite decreased the percentage of supplied phosphorus content to total phosphorus content in the new leaves. The available phosphorus content of tea soil increased with increasing amount of fertilized dolomite, The iron-bound phosphorus increased and alminum-bound phorphorus decreased by sup-plying of 300 kg./10a. dolomite.