EFFECT OF BENTONITE APPLICATION ON THE GRAIN YIELD OF RICE IN YAMAGUTI UNIVERSITY FARM

1. The bentonite application in Yamaguti Univ. Farm was effective to maintain fertilizer-N and supply N slowly to rice plant. 2. The bentonite application accounted for the increases of N-utilization, panicle number, grain number per panicle and weight of 1000 grains, increasing the grain yield of rice. 3. It was suggested that the application of reasonable amount of bentonite to Yamaguti Univ. Farm was an effective method of soil improvement for higher grain yield of rice and that the effective bentonite application adopted for the application amount of fertilizer-N was necessary. (Received june 30, 1976)