【作者】 吴峰；

【导师】 康向阳；

【作者基本信息】 北京林业大学 ， 林木遗传育种， 2013， 博士

【摘要】 白杨杂种三倍体综合杂合优势和倍性优势,具有生长迅速、纤维长度长、木质素含量低等特性,是我国北方地区优良的纸浆材新品种。为深化对白杨三倍体材性性状遗传变异的认识,促进新品种的推广及利用,本研究在鲁、豫、晋3省5地的白杨三倍体新品种区域化试验林及河北威县的栽植密度试验林的基础上,开展白杨三倍体材性性状遗传变异规律,木材材性株内纵向变异以及不同造林密度对材性变异的影响等方面的研究,取得了一定的进展。(1)明确了基因型、环境以及基因型×环境对白杨三倍体新品种材性性状的影响。白杨三倍体新品种木材基本密度、纤维性状和木质素含量都受基因型、环境以及基因型×环境的极显著影响。其中,木材基本密度和纤维性状的表型总变异主要来源于基因型效应,其次是环境效应。基因型、环境及基因型×环境效应对木质素含量表型总变异的贡献率相似。苯醇抽出物含量的表型变异中,环境效应的贡献率远高于基因型及基因型×环境效应效应。(2)对白杨三倍体新品种材性性状的遗传参数进行了估算。研究表明,白杨三倍体新品种木材材性大多数受中等到强度的遗传控制。木材基本密度和纤维性状的重复力介于0.62～0.95之间。木质素含量在除高唐地点外,品种间的差异都达到显著水平,重复力介于0.78-0.89之间。综纤维素和苯醇抽出物含量仅在高唐和郑州两地表现出品种间的显著差异,重复力介于0.71-0.93之间。进行新品种选择时,化学组分性状中应主要考虑木质素含量。此外,白杨三倍体新品种材性性状间存在不同程度的遗传相关。木材基本密度与纤维性状以及纤维性状之间存在显著的中等到强度的遗传正相关,木材主要化学组分与基本密度及纤维性状之间的遗传相关性,存在地点间的差异,在各地点间并未呈现出系统的变异规律。(3)在白杨三倍体新品种区域化试验林材性性状遗传参数估计的基础上,进行了材性性状综合选择的研究,为每个栽培地筛选出2个优良纸浆材品种。研究表明,高唐地点内的B305和B331、兖州地点内的B304和B331、襄汾地点内的B304和B306、太原地点内的B305和B333以及郑州地点内的B304和B306,是木材基本密度大,纤维性状表现良好,综纤维素含量高,木质素含量和苯醇抽出物含量较低的白杨三倍体优良纸浆材品种。(4)对白杨三倍体新品种材性性状地点组合间的B型遗传相关系数进行估算,研究表明,白杨三倍体新品种木材基本密度和纤维性状与主要化学组分相比,在各栽培地点之间的稳定性更高。木材基本密度和纤维性状在地点组合间呈显著的正的B型遗传相关,而木质素和苯醇抽出物含量在太原和其他地点之间的差异,主要来源于基因型×环境效应。(5)明确了树干高度对白杨三倍体新品种木材基本密度和纤维性状的影响。树干高度仅对纤维长度和粗度的影响达到显著水平,在纤维长度和粗度表型总变异中的贡献率分别为36.63%和3.77%。研究表明,在取样高度一致的情况下估算白杨三倍体材性性状的遗传效应,不会产生显著的系统误差。在白杨三倍体的生长过程中,木材基本密度和纤维性状受到地点间环境条件的显著影响(6)明确了栽植密度对白杨三倍体新品种木材材性的影响。随着栽植密度的降低,白杨三倍体木材基本密度呈先增加后降低的趋势,纤维长度呈逐渐增长的趋势,纤维宽度和粗度则表现出上下波动的趋势；而木材基本密度和纤维性状之间,以及各纤维性状之间的相关性呈不规则变化。栽植密度以及栽植密度×基因型对木材基本密度、纤维长度、宽度及粗度的影响均未达到显著水平,表明在2m×2m(2490株·hm-2)、2m×3m(1660株·hm-2)、2m×3.5m(1420株·hm-2)、2m×4m(1240株·hm-2)、3m×3m(1110株·hm-2)、2m×5m(990株·hm-2)及3m×4m(820株·hm-2)7个栽植密度条件下,可主要考虑白杨三倍体的生长性状,以提高单位面积的材积生长量。更多还原

【Abstract】 Triploid hybrid varieties of white poplar are combined with both hybrid and polyploidy vigors. Compared to P. tomentosa, the triploid hybrid varieties have a high growth rate, longer fibers, and lower lignin content. It was widely planted in northern China to obtain a high fiber yield from crops. In order to a clear understanding of the genetic variations of wood properties, giving a prerequisite for breeding and utilizing in triploid hybrid varieties of white poplar, the genetic variations of wood properties, variability in wood properties along the stem as well as between different initial spacing were estimated based on five sites clonal trails and a spacing trail. Major results as follows,1. Significant genotypic, environment and genotypic x environment interaction were detected for basic wood density, fiber traits and lignin contant of triploid hybrid varieties of white poplar. The phenotypic variances of basic wood and fiber traits were mainly composed by genotypic effect, secondly by environment effect. The genotypic, environment and genotypic x environment interaction effects have similar contribution for lignin phenotypic variances. However, the contribution of environment effect was much higher than the other two effects in phenotypic variances of alcohol-benzene extractives.2. The genetic parameters of wood properties were estimated. The results suggested that the most wood properties of triploid hybrid varieties of white poplar were under the moderate to high genetic controlled. The repeatability of basic wood density and fiber traits ranged from0.62-0.95. Significant differences of triploid hybrid varieties were found on lignin, excluding in Gaotang site, and the repeatability ranged from0.78～0.89. However, the significant differences of triploid hybrid varieties were only detected in Gaotang and Zhengzhou sites, and the repeatability ranged from0.71～0.93. These indicated that the lignin should be the primary consideration in wood chemical composition traits under the clonal selecting program. In addition, moderate to strong and significant positive genotypic correlations between basic wood density and fiber traits were found in five trails, however it was no consistency variations for the genotypic correlations between wood chemical composition traits and the other wood properties among individual site.3. Clone selection for pulp wood was explored by principal component analysis method with all studied traits combine based on genetic parameters. The studies suggested that the varieties of B305and B331at Gaotang site, B304and B331at Yanzhou site, B304and B306at Xiangfen site, B305and B333at Taiyuan site, as well as B304and B306at Zhengzhou site were suitable for pulp industry, according to a higher basic wood density and holocellulose, favourable fiber traits, as well as a lower lignin and alcohol-benzene extractives.4. The type B genetic correlations between different sites were evaluated for wood properties of triploid hybrid varieties of white poplar. The researches indicated that the basic wood density and fiber traits were rather stable across environments than the wood chemical composition traits. Positive and significant type B genetic correlations were found on basic wood density and fiber traits between individual sites. However, the phenotype variations of lignin and alcohol-benzene extractives between Taiyuan site and the other sites were mainly came from the effect of genotypic x environment interaction.5. The effects of sampled heights on wood basic density and fiber traits were determined. Significant height position effect for fiber length and coarseness were detected, with it composed36.63%and3.77%for phenotype variations, respectively. The results based on analysis of variance indicated that it was effective to estimate the genetic parameters of wood properties with the same simple height. Moreover, the basic wood density and fiber traits were influenced by environment during the growth of triploid hybrid varieties of white poplar.6. The effects of planting spacing on wood density and fiber traits were determined. With the lowing planted spacing, the basic wood density was initially increased then decreased. However, the fiber length increased with lowing planting spacing, whereas the fiber width and coarseness appeared fluctuated trends. In addition, the correlations between these wood properties varied with the lowing planting spacing. The research suggested that there were no significant effects of planting spacing and genotypic x spacing on basic wood density and fiber traits. These indicated that it was more effectively to improved the growth traits rather than the wood properties of triploid hybrid varieties of white poplar under the planting spacing studied in this research.更多还原