抄録
Responses of the growth, yield and its components in rice plants to the irregular disposition of planted hills under broadcasting condition were examincd by setting up ten kinds of treatment-plots differing in the coefficient of variation (CV) of the number of planted hills among four small sections in a plot. 1. The larger the CV of the number of planted hills among small sections was, the larger the degree of decrease in yield becamc, and the high correlation could be recognized between these two factors. The result was directly due to the shortage of yield compensating of plants in the dense planting sections for the decrease of yield in the sparse planting sections. 2. The bad effects of irregular disposition on the yield was considered to consist or three factors, namely, (1) the percentage of missing plant area to the total one, (2) the difference in the number of hills among the planted sections and (3) the arranged condition of planted sections in a small area. These three factors affected severely in the order of (1) > (2) > (3) on the yield. 3. The grain yield was influenced mainly by the number of panicles and the bad effect of irregular disposition upon the number of tillers and panicles was clearly seen after maximum tillering stage.
