Fundamental Studies on Yield-Forecast for Rice Plants : 15. Characters of rice yield-components in the order of culm length through the practical simplified survey method (5)

[摘要] This study is one of the serial experiments for practical use conducted based upon the characters of rice yield-components per panicle within a hill arranged in the order of culm length for the purpose to estimate the paddy rice yields and the yield-components per hill through the simplified survey method by using a few samples. This test was attempted in order to bring about the results more accurately than ever before and in order to devise a practical and simplified survey method which may serve well in the rice yield forecast before ripening period. Test samples were arranged in order of culm length per hill, and the yield-components, i. e., the total number of spikelets, percentage of ripe grains and 1, 000 ripe grains weight were measured according to the panicles. The test results obtained are summarized as follows: The total number of spikelets, percentage of ripe grains and 1, 000 ripe grains weight per panicle in the same order of culm length are represented in the form of a monomial distribution. Relation between the total number of spikelets per panicle and the order of culm length is represented in the form of the primary or secondary orthogonal regression. Relation of the percentage of ripe grains and 1, 000 ripe grains weight to the order of culm length can be represented in the form of a zero-order regression as a rule, but the zero-order regression seems to be subjected to change into the form of other regressions by the effect of environmental conditions.

[学科分类] 农业科学（综合）