随机区组少株小区中最优株在统计分析上的应用

<正>作者在福建洋口林场对11个杉木产地试验的实际例子进行了研究,试图说明随机区组少株小区中最优株在统计分析上的应用。研究结果如下: (1)四年来,我们应用小区中的最优株和小区平均数作为统计单元,其所求得的11个杉木产地的秩次基本上是相同的,其秩次相关系数是:0.9807(76年),0.9913(77年),0.9909(78年),0.9947(79年)。以上的相关系数均达到0.01的显著平准。 (2)四年来,各小区中最优株生长量的位次变异很小,这种变异只局限于第1与第2位往返变化,从未发生优株由第]位变为第3位或第4位。 (3)用两种统计单元,所求得的11个杉木产地间的期望均方值是逐年接近的。 (4)通过调整,用最优株作为统计单元所求得的11个杉木产地的遗传力和遗传增益,同样可以对试验结果作出切合实际的正确结论。

MEASURING THE BEST TREE IN EACH PLOT IN THE DESIGN OF RANDOMIZED BLOCKS WITH THE FEW TREE PLOTS IN STATISTICAL ANALYSES

The design of randomized blocks with the few-tree plots has been widely adopted in experiments in tree breeding, since it is more efficient in utilizing land, and can ensure completeness of experimental data. In this design, each plot is a smallest statistical unit, and the mean of each plot can only be obtained by measuring all the trees in a plot or by sampling. However, since this work needs a lot of time and money, it is desirable to measure the best tree in each plot and adjust the result instead.In a study of the provenance test of Chinese fir (see pp35-45, NO. 4 , 1980, Journal of NTCFP), the authors developed a method of measuring the best tree in each plot, in the design of randomized blocks with the few-tree plots in the statistical analysis, the results of which can be summarized as follows:1. During the four years of investigation the order of the means of eleven provenances of Chinese fir measured for the best tree in each plot was similar to the order of the mean measured for all trees in each plot, the correlation coefficients of the order being 0.9807 (1976) , 0.9913 (1977) , 0.9909 (1978) and 0.9947 (1979) .2 . There existed little fluctuation in the order of the best tree in each plot in the period of study. The position of a specific provenance might drop from the first place to the second in one year, and in another year might come up to the first again. But it has not been found that a best tree dropped from the first place to the third or to the fourth.3 . Difference between the expected mean squares arrived at by using the two different statistical units tended to decrease year by year.4 . With some adjustment, the heritability and genetic gains of the selected characteristics of these provenances worked out by using the best tree as unit of statistics can as well be used to draw correct conclusions.