9年生枫香的遗传变异和优良家系单株选择

为选育枫香(Liquidambar formosana)优良家系,对其24个种源310个家系的遗传变异进行分析,采用多目标决策法选育用材林优良家系及单株。结果表明,9年生枫香胸径、树高、材积、第一枝下高、冠幅和树干通直度等性状在种源和家系间存在显著差异(P0.01),以云南富宁、广西凭祥和江西湖城3个种源的材积生长表现最佳。各性状的家系遗传力属于中等遗传控制,为0.24~0.44,单株遗传力为0.20~0.50。共选出优良家系26个和单株41株,优良家系的平均胸径、树高、材积、冠幅、树干通直度分别大于总体均值的19.63%、18.56%、52.16%、5.11%和4.03%;遗传增益分别为6.67%、8.24%、20.28%、1.82%和1.75%,优良单株平均材积大于总体均值的150.25%。这为枫香育种策略制定和生产应用等提供理论依据。

Genetic Variation, Excellent Family and Individual Selection of 9-year-old Liquidambar formosana

In order to select excellent family of Liquidambar formosana, the genetic variations among 24 provenances and 310 families at 9 years old were analyzed, and excellent families and individuals were selected by multi-objective decision method. The results showed that there were significant differences in diameter at breast height (DBH), height, volume, height under branch, crown width and straight index among provenances and families (P<0.01), and the volume growth was better in provenances from Funing of Yunnan, Pingxiang of Guangxi and Hucheng of Jiangxi. The family heritability of all traits was moderate genetic control, ranged from 0.24 to 0.44, and the individual heritability was from 0.20 to 0.50. There were 26 excellent families and 41 excellent individuals were selected. The average DBH, tree height, volume, crown width and straight index of excellent families were larger than ensemble average for 19.63%, 18.56%, 52.16%, 5.11% and 4.03%, respectively, and their genetic gain was similar for 6.67%, 8.24%, 20.28%, 1.82% and 1.75%. The average volume of excellent individuals was larger than ensemble average for 150.25%. So, these would provide a theoretical basis for the breeding strategy making and application in production of L. formosana.