四川省桤木种源单株生物质产量的遗传变异和选择初探

Study on Genetic Variation and Selection of Dry Trunk Weight in Alnus cremastogyne

对6年生四川省桤木15个种源51个家系在湖北、江西、福建3个试验点试验林的单株生物质产量进行了研究,结果表明:桤木种源3个地点6年生的平均单株生物质产量为6.15kg。单株生物质产量种源间、种源内家系间差异显著。单株生物质产量具有极显著的地点效应,单株生物质产量种源×地点、家系×地点交互作用显著。3个地点单株生物质产量种源遗传力为0.27～0.75,家系遗传力为0.17～0.83,表明单株生物质产量受到中度到强度的遗传控制。材积(直接通径系数0.791)对单株生物质产量控制作用最大,其次为树高(直接通径系数0.396)和木材基本密度(直接通径系数0.256)。树高、胸径和冠幅通过材积对单株生物质产量的间接通径系数较大。四川省金堂盐井、盐亭、金堂淮口、沐川和邛崃5个桤木种源初选为工业用材林优良种源。

According to the 6-year-old data of Alnus cremastogyne, the experiment analysis has been made for dry trunk weight of single tree of the 15 provenances and 51 families in 3 sites. It proved that the means of dry trunk weight was 6.15 kg. There was significant difference among provenances and families in dry trunk weight, meanwhile, the interaction between provenance and site, family and site in dry trunk weight was statistically significant. Genetic parameter analysis showed that provenance heritability and family heritability of dry trunk weight were 0.27 - 0.75, 0.17 - 0.83, respectively, and showed that dry trunk weight of A. cremastogyne was genetically controlled in moderate to strong degree, so it was feasible to improve the dry trunk weight of A. cremastogyne. Dry trunk weight was the most suitable index to show production efficiency of A. cremastogyne pulp wood plantation. The direct path coefficient of volume was highest （0.791） to dry trunk weight. The next was height （0.396）and wood density （0. 256）. Tree height, DBH and crown range had effects on dry trunk weight indirectly. The best five provenances from Sichuan Province, which were Yanjing of Jintang, Huaikou of Jintang, Muchuan, Qionglai and Yanting, have been selected on the basis of combined index.