湿地松子代测定中合适家系大小及小区大小的探讨

The Study of Suitable Family Sizes and Plot Sizes in Progeny Testing of Pinus elliottii

子代测定的主要目的是评价亲本的遗传品质,估计遗传参数以及为高世代育种提供材料等。田间设计的合理与否关系到试验结果的准确性。目前,国外有关田间设计的研究表明,在亲本排序方面,小区大小的效率因研究性状、林龄的不同而异,Conkle与Correll等发现,林分中林木间发生激烈竞争之前,单株小区最为有效,而后是多株小区。

Two progeny testing plantations which contained the same open-pollinated progenies of slash pine (Pinus elliottii) were established. These two plantations were of randomized and complete block design, 48 offspring per family and 4-tree plot. Height and diameter at breast height were measured in the 5-year-old progeny test stands, and these data were used to analyze the relationship between families (or parents) ranking or family heritability and family sizes or plot sizes. The results show that the required minimum family size is 30 for obtaining reliable rank per family and family h2 in one single site test. But in two site tests, the minimum family sizes are different for family ranking and family h2, they are 10 and 30 respectively. Different sites and family sizes have different optimum plot sizes, in general, two- or three-tree plot is more efficient than single- or four-tree plot for estimating family ranking and family h2.