1990 Volume 59 Issue 4 Pages 721-726
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.
