马尾松自由授粉家系产脂力的年度变化及遗传分析

Age Changes and Genetic Analysis of the Resin-Yielding Capacity of Open-Pollinated Families of Masson Pine

以来自马尾松天然群体的49个高产脂优树半同胞家系子代为对象,测定6个年度产脂力。结果表明:马尾松在早期的产脂力随树龄的增长而迅速增大,13年后进入稳定期。不同家系的产脂力差异显著,但产脂力变异幅度随树龄的增长而降低。产脂力变异受中等遗传控制,其中早期遗传力较高,后期遗传力较低且稳定,家系遗传力明显高于单株遗传力。早期与成熟期的产脂力具有紧密的遗传正相关,且相关性随树龄的增长而增加。产脂力的早期选择效率随树龄的增大而提高,11年时达到0.813,是理想的早期选择时间节点。利用综合育种值法筛选到13个优良产脂家系,入选家系的年度育种值均显著高于对照,且随树龄的增大而增加。

A total of 49 open-pollinated families of Masson pine （Pinus massoniana） collected from plus trees of natural forests were used to test the resin-tapping capacity for 6 years. Results showed that the resin-yielding capacity （RYC） increased rapidly at early ages and maintained at a stable level after age 13 a. Variance analysis detected plenty of genetic variations in RYC among families. Additive genetic coefficients of variations （CV） showed a decreasing RYC trend with ages. The genetic variations were under middle-level genetic control. Heritability also showed a decreasing trend with ages, and family heritability was apparently higher than individual heritability. There were close positive genetic correlations in RYC between early and mature ages,and the correlations displayed an increasing trend with ages. Early selection at age 11 a was highly effective since the efficiency reached 0. 813. A selection based on comprehensive breeding values screened out 13 superior families whose breeding values （BVs） were much higher than that of control and displayed an increasing trend with ages.