【作者】 巩其亮；

【导师】 邢世岩；

【作者基本信息】 山东农业大学 ， 森林培育， 2009， 博士

【摘要】 本研究以来自我国9个省和日本的139个银杏雌株无性系为试材,系统地研究了其生长性状、木材的解剖结构、物理力学特性、化学性质以及它们的遗传变异规律,在此基础上对无性系进行了评价选择,主要结论如下:1.性状的变异生长指标中,除新梢粗和新梢长外,材积、接口上粗、接口上高等生长指标在无性系间的差异都非常显著。在银杏木材中存在两种形态、结构不同的宽窄管胞,其中宽管胞为银杏木材的主要管胞类型。管胞的横截面形态变异较大,管胞长度、微纤丝角、双壁厚、腔径、壁腔比、弦向直径、径向直径等形态特征指标在无性系间有较大的变异。银杏具缘纹孔形态和纹孔排列方式在无性系间和无性系内变异也较大。银杏木材的密度、干缩率、生长应变等物理力学性质在不同无性系间和不同径向位置、高度上存在较大变异。抗压强度在不同无性系间的差异非常明显。银杏木材的冷水抽出物含量、热水抽出物含量、1%NaOH抽出物含量、苯醇抽出物含量、木质素含量、纤维素含量、灰分含量等基本化学性质在无性系间差异较大;银杏木材的耐腐能力在无性系间差异明显;各无性系木材在不同热解阶段的起始和终止温度、质量损失率和放热量都存在明显的差异,不同热解阶段的表面活化能差异也非常显著。2.性状的遗传控制材积、接口上粗、接口上高、冠幅等生长指标的重复力都在0.70以上,其它生长性状的重复力相对较弱;微纤丝角、双壁厚、腔径、壁腔比、弦向直径、径向直径6个管胞特征指标的重复力都在中等以上,其中微纤丝角和弦向直径的重复力达到了0.70以上;在物理力学指标中,除顺纹抗压强度和表面轴向生长应变的重复力较低外,干缩指标和基本密度的重复力都达到了0.60以上;银杏木材化学性质的重复力相差较大,其中木质素、纤维素、灰分、苯醇抽出物含量等4项指标的重复力较大,达到了0.70以上,在无性系内较为稳定。3.性状的相关性生长性状间的相关性较强,除了新梢粗与新梢叶数呈负相关外,大部分指标间都为正相关,并且相关性较高。在管胞的特征指标中,微纤丝角与壁腔比呈正相关,与双壁厚、腔径、弦向直径、径向直径呈负相关,除与双壁厚的相关性较弱外,与其它指标的相关性都达到了极显著水平。另外,腔径、径向直径和弦向直径间相关性也都较强。6个干缩指标及表面生长应变间为正相关,相关性都达到了极显著水平。基本密度与顺纹、横纹抗压强度间也为正相关,相关性也都达到了极显著水平。主成分分析表明:可以把物理力学指标归为反映银杏木材干缩特性和力学性质的两类指标。大部分化学指标间的相关系数都不大,其中不同抽出物含量之间,纤维素与木质素含量之间,纤维素含量与耐腐能力,木质素含量与热分解指标间的相关性较高。分别分析了生长、解剖、化学指标与物理力学指标间的相关性,结果表明:生长指标与干缩指标间存在负相关关系,与其它物理力学指标间相关性较弱;微纤丝角与干缩率呈负相关,与基本密度呈显著的正相关,与顺为抗压强度和表面生长应变都呈弱的负相关;径向直径、弦向直径与干缩率间都呈正相关,与基本密度呈负相关,与顺纹抗压强度呈弱的负相关;化学性质与物理力学性之间的相关性较弱。主要表现为:冷水抽出物与基本密度、顺纹抗压强度呈显著的正相关。苯醇抽出物含量与弦向干缩率、表面生长应变呈极显著负相关。木质素和纤维素含量与顺纹抗压强度呈正相关,与表面生长应变呈极显著负相关。4.无性系选择根据遗传参数及指标间相关性分析结果,在生长、解剖、物理力学、化学四类指标体系内,对不同试验地点的无性系进行了选择,分别选出多个生长量大,解剖结构好,物理力学特性稳定和化学组成适宜的优良无性系。根据指标间的相关性和重复力大小,从4类指标中选出接口上粗、管胞弦向直径、体积干缩率、基本密度、木质素含量共5个指标作为无性系选择的综合指标,建立指数选择方程为:I=0.1171x1-0.3749x2+12.0533x3-0.7948x4+0.7120x5综合选择指数的准确度为rH I=0.9982,指数遗传力h I2=0.9225,综合育种值选择进展△H =2.5942。通过对郯城孙出口16个无性系的选择,选择指数最大的无性系为005#,其生长、解剖、物理力学和化学组成等综合指标优于其它无性系,选择效果较好,说明这个选择评价指标体系能够较为全面地反映银杏木材的基本性状。本文还对银杏木材的系统进化、指标间的相关性、遗传控制以及无性系选择等问题进行了讨论。更多还原

【Abstract】 Taking 139 Ginkgo biloba L. female clones from 9 provinces in China and Japan as test materials, this dissertation systematically studied their growth traits, wood anatomical structure, physical-mechanical properties, chemical properties as well as their law of genetic variation. On that basis, this study made a evaluation and selection on clones. The main conclusions were as follows:1. Trait variationAmong all the growth traits, except for the diameter and length of new shoots, there were very significantly differences among different clones.There were two kinds of wide and narrow tracheids with different shapes and structure in wood of Ginkgo biloba L. and the former was the main tracheid type. The cross-sectional shape of tracheid mutated greatly. The shape features indexes of the tracheid, including tracheid length, microfibril angle, double-wall thickness, lumen diameter, the ratio of cell wall to cavity, tangential diameter and radial diameter, were quite variable among the clones. And there were great variations of the shape and the arrangement modes of bordered pits among and within the clones.There were great variations of physical and mechanical properties of Ginkgo wood, such as wood density, shrinkage rate, and growth strain, among different clones and at different radial locations and heights. The maximum crushing strength differed significantly among different clones.There were significant differences of chemical properties, including the content of cold water, hot water, 1%NaOH, alcohol-benzene, lignin, cellulose, and of ash among clones. The corrosion resistance of wood differed greatly among clones. There were significant differences of the starting and final temperatures, as well as the rate of mass loss and thermal discharge at different thermal decomposition stages between different clones. And the surface activation energy differed greatly at different thermal decomposition stages between different clones,too.2. Genetic control of traitsThe repeatability of stem volume,diameter upon rootstock,length above rootstock,crown-width was over 0.70,and the repeatability of other growth traits were relatively low; The repeatability of the six tracheid feature indexes: tracheid microfibril angle, double-wall thickness,lumen diameter,ratio of cell wall to cavity,tangential diameter and radial diameter, were above the average. The repeatability of microfibril angle and tangential diameter were over 0.70; Among physical-mechanical properties indexes, the repeatability of air-dried shrinkage rate and basic density was over 0.60, except for the lower repeatability of Maximum crushing strength and surface longitudinal growth strains; The repeatability of chemical properties differs greatly, and repeatability of lignin,cellulose, ash and alcohol-benzene was much higher above 0.70 and was stable among the clones.3. Correlation of traitsCorrelations among the growth traits were relatively strong. The correlations among most indexes were positive with higher correlation coefficient, except for the correlation of the diameter of new shoots and the number of new shoot leaves being negative. Among the indexes of tracheid features, microfibril angle presented a positive correlation with Ratio of cell wall to cavity, and presented a negative correlation with double-wall thickness,diameter of cavity,radial diameter and tangential diameter. And except for the weak correlation with double-wall thickness, its correlation with other indexes reached a very significant level. The Correlation between lumen diameter, radial diameter and tangential diameter were also very strong.The 6 shrinkage indexes and the surface growth strain had a positive correlation at a significant level. The correlation between basic density and maximum crushing strength was also positive at a significant level. The analysis of principal components showed that the entire physical-mechanics indexes could be classified into two categories of indexes which reflected the shrinkage properties and mechanical properties of Ginkgo wood.The correlation coefficients of most chemical indexes were not significant. the correlation among different extracts,the correlation between the content of cellulose and lignin,the correlation between the content of cellulose and the corrosion resistance, and the correlation between the content of lignin and the indexes of thermal decomposition were relative strong.This study also analyzed the correlation of growth traits, wood anatomy and chemical properties with physical-mechanical properties. The conclusions showed that: Growth indexes and dried-air shrinkage indexes had a negative correlation, and it had a weak correlation with other physical-mechanical indexes; microfibril angle presented a negative correlation with shrinkage rate, a significant positive correlation with basic density,and a weak negative correlation with Maximum crushing strength and surface growth strains; Radial diameter and tangential diameter of tracheids presented a positive correlation with shrinkage rate, a negative correlation with basic density, and a weak negative correlation with Maximum crushing strength; There were a weak correlation between chemical properties and physical-mechanical properties, which principally presented as follows: there were significant positive correlation between cold water extracts and basic density as well as maximum crushing strength. There were a significant negative correlation between alcohol-benzene extracts and tangential shrinkage rate as well as surface growth strain. There were a positive correlation between lignin and cellulose as well as Maximum crushing strength, and a very significant negative correlation with surface growth strains.4. Selections of clonesAccording to the analysis results of genetic parameters and correlations of different indexes, within the four index systems of growth, anatomy, physical mechanics, and chemistry, we selected superior clones with high growth, good anatomical structures, stable physical-mechanics features, and proper chemical components in different test fields. According to the correlation and the repeatability, from 4 categories of indexes, this study chose 5 indexes, which were diameter upon rootstock,tangential diameter, dried-air shrinkage rate of volume, basic density and lignin content, as the comprehensive indexes to select clones, and established a index selection mathematical equation : I=0.1171x1-0.3749x2+12.0533x3-0.7948x4+0.7120x5The rate of accuracy of comprehensive selective index rH I=0.9982,index hereditary captivity h I2=0.9225,Progress in integrated breeding selection△H =2.594. This study selected 16 clones in Sun Chukou of Tan cheng with the largest selecting index 005# . its comprehensive indexes of growth, anatomy, physical-mechanics, and chemical components were superior to other clones. This showed that this system of selection index could reflect the basic traits of Ginkgo wood comprehensively.This dissertation also made a discussion about systematic evolution, correlation among indexes, genetic control and clone selection of Ginkgo biloba L.更多还原