光皮桦优树子代性状遗传变异及选择

Selection and genetic variations of traits among plus trees of Betula luminifera

在福建省选择101株光皮桦(BetulaluminiferaH.Winkl.)优树,利用其中55株优树的种子在福建省邵武卫闽林场开展子代测定分析。结果表明,光皮桦种内存在丰富的遗传变异,优树子代间差异显著,这些差异主要由遗传因素控制;3a生树高家系遗传力、单株遗传力分别为0.446和0.327,胸径的家系遗传力和单株遗传力分别为0.431和0.291;各生长性状与冠幅间存在紧密的相关性;以3a生树高为主要指标,从参试的家系中初步选出12个优良家系和31株优良个体,优良家系的树高和胸径的平均遗传增益分别为7.95%和11.87%;优良个体的树高和胸径的平均遗传增益分别高达26.60%和40.37%,选择效果非常明显。这些优良家系和个体可用作种子园建园材料或无性繁殖材料。

One hundred and one plus trees of Betula luminifera H. Winkl. were selected from Fujian Province, 55 of which were used in progeny test in State-owned Forest Farm of Weimin, Shaowu City of Fujian Province. Based on the investigation of 3-year-old traits from different families, it was showed that there were abundant variations within the B. luminifera and very significant difference among families in tree height, tree basal diameter, tree diameter at breast height, crown width, survival rate and preserving rate. The variations were mainly controlled by genetic factors.\ The family heritabilities of height and diameter at breast height of 3-year-old progeny were 0.446 and 0.431 respectively. The individual heritabilities of height and diameter at breast height of 3-year-old progeny were 0.327 and 0.291 respectively. The correlation coefficients among growth traits and crown width were very high. According to height trait,12 excellent families were preliminary selected, the average genetic gain for height and diameter at breast height were 7.95% and 11.87% respectively. Thirty-one excellent individuals were preliminary selected, the average genetic gain for height and diameter at breast height were 26.60% and 40.37% respectively. The selection effect was very significant. These selected families and individuals could be used for seed orchard or vegetative propagation.