马尾松实生种子园自由授粉子代测定及亲本家系选择增益估算

以福建省白砂国有林场的马尾松实生种子园自由授粉子代测定林为材料,分析了5、6年生家系生长量(树高、胸径及材积)及形质指标(通直度、冠幅及侧枝粗度)的遗传变异规律,估算了各性状的遗传力。结果表明,材积、胸径、树高生长性状及冠幅、通直度、侧枝粗度等形质指标在家系间和家系内均存在显著的遗传差异,且家系内变异大于家系间。家系、单株遗传力分别在0.493 0.731、0.080 0.199之间。利用最佳线性预测的单性状(材积)及多性状联合(材积、冠幅、侧枝粗度及通直度)估算了6年生家系育种值。分析了材积单性状选择方式、多形状联合选择以及冠幅约束选择在不同入选率下亲本家系的预测及现实遗传增益(材积及通直度)的变化规律,结果表明,在等权重条件下,联合材积及通直度指标进行亲本家系选择是最佳选择方式,能够获得相对较高的遗传增益。

Estimation of Parents Genetic Gain by Open-pollinated Progeny Test of Seedling Seed Orchard of Masson Pine

Using the progeny test plantation of Pinus massoniana seedling seed orchard located in Baisha Forestry Farm, Fujian province as materials, the genetic variations, heritabilities and increments (height, diameter at breast height, and stem volume) and form (stem straightness, crown width, and branch diameter) traits of P. massoniana at age 5 and 6 were estimated and analyzed. The genetic variations differed among traits. Obvious genetic variations possessed among and within families and intra-family variation (85%) was a main source. Family and individual heritabilities ranged from 0.493 to 0.731, and 0.080 to 0.199, respectively. Best linear prediction with stem volume and multi-traits (stem volume, crown width, branch diameter and stem straightness) was used to estimate the aggregated breeding values of families at age 6. Furthermore, realized and predicted genetic gains of female parents with different selection methods and selection rates were presented, in which the even-weighted multi-traits joint selection was the best way for female parent family selection and could get relatively higher genetic gains.