A Basic Study on Field Experiment and Investigation Methods in Rice Plant : II. Coefficient of variation and standard sample size in the survey of quantitative characters of mechanically transplanted rice

[摘要] In order to obtain standard sample size in sample survey of quantitative characters of mechanically transplanted rice, the coefficients of variations (CV) of characters were investigated at growth period of maximum tiller number stage, full heading stage and maturing stage. CV of number of seedling per hill in mechanically transplanted rice was about 40%. CV of characters such as number of tiller, number of panicle, fresh weight, number of spikelet per hill and panicle weight were larger than the CV in hand-transplanted rice on account of variation of number of seedling per hill. The difference between the CV in mechanically transplanted rice and the CV in hand-transplanted rice was large in maximum tiller number stage, but the difference decreased according to growth. It was judged that standard sample sizes of these characters in maximum tiller number stage were 2.3 times the sizes in hand-transplanted rice, the sample sizes in full heading stage were 1.7 times the sizes in hand-transplanted rice, and the sample sizes in maturing stage were 1.2 times the sizes in hand-transplanted rice. While, CV of characters such as plant height, culm length and panicle length were almost equal to the CV in hand-transplanted rice. Therefore, it was judged that standard sample sizes of these characters were equal to the sizes in hand-transplanted rice.

[学科分类] 农业科学（综合）

[关键词] Coefficient of variation;機械移植;Field experiment;水稲;Mechanically transplant;1株植付け本数;Number of seedling per hill;標本数;Quantitative character;標本調査;Rice plant;変動係数;Sample size;圃場試験;Sample survey;量的諸形質