赤桉抗风特性及其重要性状的关联分析
发布时间：2019-07-09 05:58
【摘要】：我国南方沿海夏季台风频繁,风害严重影响沿海地区的生态安全以及相关产业的发展,尤其对林木生长构成极大威胁,成为制约桉树人工林可持续发展的重要因素之一。选育优良抗风品系是保证我国沿海地区桉树商品林可持续发展的重要措施。赤桉(Eucalyptus camaldulensis)为优质的硬木材,耐旱、耐瘠、抗风、抗病能力强,为我国桉树树种改良的重要遗传材料。本论文以114个赤桉家系(半同胞)为材料对其生长、材性、物理力学、化学成分等26个性状进行跟踪调查,对各个性状进行遗传变异分析并通过相关性分析寻找影响桉树抗风的主要影响因素。通过风害模拟(拉树实验)分析风与重载荷下的变形以及抗风主要影响因子,并对赤桉家系抗风特性进行评估,最终获得影响赤桉抗风的主要影响因子及选育出优良抗风家系。桉树抗风性是由众多复杂因素引起的,本研究在获得影响桉树抗风的主要影响因素的基础上利用SSR分子标记技术进行关联分析,对桉树抗风相关性状进行关联分析,系统剖析赤桉抗风的遗传基础,发掘优良SSR位点。本研究将有助于建立桉树抗风育种分子标记辅助选择体系,为发掘和利用重要的桉树抗风基因资源奠定基础,为后续相关研究提供理论依据。主要研究结论如下:1、赤桉家系各生长性状间存在着丰富的遗传变异,家系间性状各性状中家系遗传力均高于单株遗传力,说明家系的选择潜力更大一些。早期赤桉(1年生)各家系性状间存在着丰富的遗传变异,具有很强的家系和家系内单株选择潜力。风害指数与家系生长性状的遗传相关系数以冠幅与体积最大,抗风性与林木大小相关性不强,回归方程也表明抗风性与其生长性状关联程度不大,相反林木植株越速生(即材积越大),更易遭受风害。2~3生赤桉抗风性研究表明,平均风害指数为2级以下,林木的风害指数与其林木大小(树高、单株材积)呈强负相关,不同家系间抗风性存在着差异且具有遗传性,而且某些性状遗传控制水平相对较高。3~4年生赤桉家系风害等级与树高、冠幅、材积、树皮厚度的Pearson相关性呈极显著负相关关系。说明树木越高、材积越大越抗风。3~4年生赤桉家系抗风性研究表明赤桉抗风能力与树高、胸径、材积有关。2、木材密度在赤桉家系间、不同家系部位间以及其家系和部位交互间差异性均不显著,40月生的赤桉木材密度属于小级,即属轻木材。根据木材物理力学分级标准划分赤桉干缩率属于III级,容易开裂,树干底部差异干缩值较中部、梢部差异干缩值大,所以底部更容易开裂和变形。赤桉不同家系间力学性状(抗弯强度、抗弯弹性模量、顺纹抗剪强度、顺纹抗压强度)差异性极显著,不同部位间抗弯弹性模量差异极显著,其余指标差异性不显著。研究发现林木大小(树高、胸径、材积)是影响桉树抗风性能的主要因子,其次是材性因子。单株立木风害程度与立木大小密切相关,也与立木的材性如纤维宽度、Pilodyn值、应力波值有着较强的相关性。从木材基本密度和干缩率、物理力学(抗弯强度、抗弯弹性模量、顺纹抗剪强度、顺纹抗压强度等)等力学性状与赤桉抗风性之间相关性可以看出二者之间相关性不显著,风害指数与木质素、综纤维素、α-纤维素、半纤维素之间相关性均不显著(P0.05),从相关性分析发现赤桉抗风性能与木材物理力学及化学成分关系不大。3、进一步通过风害模拟(拉树实验)获得的拉力三因素(立木所受拉力、树干变形程度及倾斜角度)与生长、材性、物理力学、化学成分等26个性状进行回归分析及典型相关分析发现:影响赤桉树干拉树三因素的主要影响因子为树高、材积、胸径、树皮厚度、纤维长度、气干干缩率、抗拉强度、抗拉弹性模量、综纤维素含量。其中对赤桉抗风影响最大的赤桉的生长性状即树高、材积、胸径,其次是纤维长度、抗拉强度。4、遗传多样性分析参试材料为8个赤桉群体的109株样品,参试标记为覆盖全基因组的107个SSR位点。55个中性的基因组SSRs揭示了赤桉群体多样性水平较高,共检测到1116个等位片段,平均每位点20.3个等位片段,PIC为0.3508~0.9489,平均0.771,位点均为多态性较高的位点,HE平均值为0.718,说明赤桉发生高度杂合,Fst平均值为0.066,群体间的遗传分化不显著,分子方差分析中群体间方差分量仅占1%,说明遗传变异主要存在于群体内。从赤桉Nei(1972)遗传距离分析发现澳大利亚亚群遗传背景差异较大。赤桉群体具有丰富的遗传多样性,可进行抗风品系选育和遗传改良的基因库。5、利用800多对覆盖全基因组的SSR标记通过PCR优化以及对8株强抗风和8株弱抗风赤桉基因池的筛选,得到在两类基因池中等位频率差异较大的107个SSR标记用于赤桉抗风相关性状的SSR关联分析。赤桉家系树高、胸径、材积、风害指数等4个性状与26个SSR位点存在显著连锁(P0.05),可解释生长及抗风性状表型变异的9.26%~71.14%。其中树高相关位点最多,为13个,其他性状5~8个。26个关联位点中EUCeSSR235位点对风害指数的解释率最高为71.14%,EUCeSSR570位点对树高解释率最低为9.26%,平均解释率为36.27%。位点EUCeSSR332与树高、胸径、材积、风害指数等4个性状均显著相关联,该位点对4个性状表型变异解释率相对较高,超过60%。位点EUCeSSR484、EUCeSSR352、EUCeSSR570和EUCeSSR422与树高和风害指数等2个性状均相关联,EUCeSSR489和EUCeSSR114位点与树高和材积等2个性状相关联。
文内图片：
图片说明：09份赤桉种质资源群体结构图
[Abstract]:The frequent occurrence of typhoon and wind damage in the coastal areas of the south of China have seriously affected the ecological security of the coastal areas and the development of the related industries, in particular, it poses a great threat to the growth of the trees, and becomes one of the important factors to restrict the sustainable development of the eucalyptus plantation. The breeding of the good wind-resistant strain is an important measure to ensure the sustainable development of the eucalyptus goods in the coastal area of China. Eucalyptus camaldulensis is an important genetic material for the improvement of eucalyptus tree species in China. In this paper,26 characters, such as growth, material property, physical mechanics, chemical composition and so on, were investigated by using 114 red eucalyptus family (half-siblings), and the main influencing factors that affected the wind resistance of the eucalyptus were found through the analysis of the genetic variation and the correlation analysis. The wind and heavy load deformation and the wind-resistant main influence factors are analyzed by the wind damage simulation (Rtree experiment), and the wind resistance characteristics of the Eucalyptus urophylla family are evaluated, and the main influence factors affecting the wind resistance of the Eucalyptus urophylla are obtained, and the excellent anti-wind family is selected. The wind resistance of Eucalyptus is caused by a number of complex factors. This study is based on the main influencing factors that affect the wind resistance of the eucalyptus, and uses the SSR molecular marker technology to carry out the correlation analysis. The correlation analysis of the wind resistance of the eucalyptus is carried out, and the genetic basis of the wind resistance of the eucalyptus is analyzed. And the excellent SSR locus is excavated. This study will help to establish a molecular marker-assisted selection system for wind-resistant breeding of eucalyptus, laying the foundation for exploring and using the important anti-wind gene resources of the eucalypt, and providing a theoretical basis for the follow-up research. The main results of the study are as follows:1. There are abundant genetic variation among the growth characters of the family of Eucalyptus, and the heritability of the family is higher than the heritability of the single plant, and the selection potential of the family is larger. There are abundant genetic variation among the characters of the early Eucalyptus (1-year-old), which has a strong family and single-plant selection potential in the family. The genetic correlation coefficient between the wind-damage index and the growth character of the family is the largest, the resistance to wind resistance and the size of the tree is not strong, and the regression equation also shows that the resistance to wind resistance is not related to the growth character of the family, and the faster the tree plant grows (i.e. the larger the volume product), The results showed that the average wind-damage index was below grade 2, and the wind-hazard index of the forest was negatively correlated with the tree size (tree height and single-plant volume). The genetic control level of some characters was relatively high. The correlation of the wind-damage grade of the 3-4-year-old Eucalyptus family with the tree height, the crown width, the volume of the material and the Pearson correlation of the bark thickness was negatively correlated. It is indicated that the higher the tree, the greater the volume of the material, and the wind resistance of the 3-4-year-old Eucalyptus urophylla family shows that the wind resistance of the eucalyptus is related to the height of the tree, the diameter of the breast and the volume of the tree. There was no significant difference in the inter-family and family and site interactions among the different families, and the wood density of the 40-month-old Eucalyptus grandis belongs to the small grade, which belongs to the light wood. According to the physical and mechanical classification standard of the wood, the dry shrinkage rate of the eucalyptus is grade III, is easy to crack, the dry shrinkage value of the difference between the bottom of the trunk and the middle part of the trunk is relatively large, and the difference in the dry shrinkage of the tip part is large, so that the bottom is more prone to cracking and deformation. The difference of the mechanical properties (bending strength, flexural modulus, the shear strength and the compressive strength) of the different parts of Eucalyptus grandis is very significant, the difference of the flexural modulus of the different parts is very significant, and the difference of the other indexes is not significant. The study found that the size of trees (height, DBH, volume of wood) was the main factor that affected the wind resistance of the eucalyptus, followed by a material factor. The degree of wind damage of a single plant is closely related to the size of the vertical wood, and also has a strong correlation with the wood properties such as the fiber width, the Pilodyn value and the stress wave value. The correlation between the mechanical properties such as the basic density of the wood and the dry shrinkage, the physical mechanics (bending strength, the flexural modulus of bending, the shear strength of the line, the compressive strength of the smooth grain, etc.) and the anti-wind resistance of the eucalyptus urophylla can be seen to show that the correlation between the two is not significant, and the wind-hazard index is similar to that of the lignin and the heddle, The correlation between cellulose and hemicellulose was not significant (P0.05). From the correlation analysis, it was found that the anti-wind property of Eucalyptus globulus was not related to the physical and chemical composition of wood. The regression analysis and typical correlation analysis of 26 characters, such as growth, material property, physical mechanics, chemical composition and so on, found that the main influencing factors that affect the three factors of the tree trunk deformation are the height of the tree, the volume of the material, the diameter of the breast, the thickness of the bark, the fiber length, Dry shrinkage rate, tensile strength, tensile elastic modulus and total cellulose content. in which, the growth characteristics of the Eucalyptus globulus which have the greatest influence on the wind resistance of the eucalyptus are the tree height, the material product, the DBH, the second is the fiber length, the tensile strength, and the genetic diversity analysis and test material is 109 samples of the eight eucalyptus groups, A total of 107 SSR loci covering the whole genome were identified.55 neutral genomic SSRs revealed a high diversity of Eucalyptus globulus, and a total of 1116 alleles were detected, with an average of 20.3 alleles per point, a PIC of 0.35508-0.9489, an average of 0.771, and a site with a higher polymorphism. The mean value of HE is 0.718, which indicates that the height of Eucalyptus is heterozygous, the average of Fst is 0.066, the genetic differentiation among the groups is not significant, and the variance component of the inter-population variance in the molecular analysis of variance is only 1%, indicating that the genetic variation is mainly present in the population. The genetic background of the subpopulation in Australia was found to be different from the genetic distance analysis of Nei (1972). The population of Eucalyptus grandis has rich genetic diversity, and can be used for the breeding of wind-resistant strains and the genetic improvement of the gene library. The SSR-associated analysis of the resistance-related traits of Eucalyptus urophylla was obtained by using 107 SSR markers with a large difference in the medium-position frequency of two types of gene pools. There was a significant linkage with 26 SSR loci (P0.05), which could explain the growth and resistance to the phenotypic variation of 9.26% ~ 71.14%. Among the 26 associated sites, the rate of the ECeSSR235 site to the wind-hazard index was 71.14%, the lowest in the ECeSSR570 site was 9.26%, and the average interpretation rate was 36.27%. The site ECeSSR332 was associated with four traits such as tree height, DBH, volume and wind-damage index, and the interpretation rate of the four traits was relatively high, over 60%. The site EUCSSR484, EUCSSR352, EUCSSR570 and EUCSSR422 were associated with two traits, such as the high tree height and the wind hazard index, and the EUCSSR489 and EUCSSR114 sites were associated with 2 traits such as tree height and volume.
【学位授予单位】：中国林业科学研究院
【学位级别】：博士
【学位授予年份】：2017
【分类号】：S792.39
，
本文编号：2511907
文内图片：
图片说明：09份赤桉种质资源群体结构图
[Abstract]:The frequent occurrence of typhoon and wind damage in the coastal areas of the south of China have seriously affected the ecological security of the coastal areas and the development of the related industries, in particular, it poses a great threat to the growth of the trees, and becomes one of the important factors to restrict the sustainable development of the eucalyptus plantation. The breeding of the good wind-resistant strain is an important measure to ensure the sustainable development of the eucalyptus goods in the coastal area of China. Eucalyptus camaldulensis is an important genetic material for the improvement of eucalyptus tree species in China. In this paper,26 characters, such as growth, material property, physical mechanics, chemical composition and so on, were investigated by using 114 red eucalyptus family (half-siblings), and the main influencing factors that affected the wind resistance of the eucalyptus were found through the analysis of the genetic variation and the correlation analysis. The wind and heavy load deformation and the wind-resistant main influence factors are analyzed by the wind damage simulation (Rtree experiment), and the wind resistance characteristics of the Eucalyptus urophylla family are evaluated, and the main influence factors affecting the wind resistance of the Eucalyptus urophylla are obtained, and the excellent anti-wind family is selected. The wind resistance of Eucalyptus is caused by a number of complex factors. This study is based on the main influencing factors that affect the wind resistance of the eucalyptus, and uses the SSR molecular marker technology to carry out the correlation analysis. The correlation analysis of the wind resistance of the eucalyptus is carried out, and the genetic basis of the wind resistance of the eucalyptus is analyzed. And the excellent SSR locus is excavated. This study will help to establish a molecular marker-assisted selection system for wind-resistant breeding of eucalyptus, laying the foundation for exploring and using the important anti-wind gene resources of the eucalypt, and providing a theoretical basis for the follow-up research. The main results of the study are as follows:1. There are abundant genetic variation among the growth characters of the family of Eucalyptus, and the heritability of the family is higher than the heritability of the single plant, and the selection potential of the family is larger. There are abundant genetic variation among the characters of the early Eucalyptus (1-year-old), which has a strong family and single-plant selection potential in the family. The genetic correlation coefficient between the wind-damage index and the growth character of the family is the largest, the resistance to wind resistance and the size of the tree is not strong, and the regression equation also shows that the resistance to wind resistance is not related to the growth character of the family, and the faster the tree plant grows (i.e. the larger the volume product), The results showed that the average wind-damage index was below grade 2, and the wind-hazard index of the forest was negatively correlated with the tree size (tree height and single-plant volume). The genetic control level of some characters was relatively high. The correlation of the wind-damage grade of the 3-4-year-old Eucalyptus family with the tree height, the crown width, the volume of the material and the Pearson correlation of the bark thickness was negatively correlated. It is indicated that the higher the tree, the greater the volume of the material, and the wind resistance of the 3-4-year-old Eucalyptus urophylla family shows that the wind resistance of the eucalyptus is related to the height of the tree, the diameter of the breast and the volume of the tree. There was no significant difference in the inter-family and family and site interactions among the different families, and the wood density of the 40-month-old Eucalyptus grandis belongs to the small grade, which belongs to the light wood. According to the physical and mechanical classification standard of the wood, the dry shrinkage rate of the eucalyptus is grade III, is easy to crack, the dry shrinkage value of the difference between the bottom of the trunk and the middle part of the trunk is relatively large, and the difference in the dry shrinkage of the tip part is large, so that the bottom is more prone to cracking and deformation. The difference of the mechanical properties (bending strength, flexural modulus, the shear strength and the compressive strength) of the different parts of Eucalyptus grandis is very significant, the difference of the flexural modulus of the different parts is very significant, and the difference of the other indexes is not significant. The study found that the size of trees (height, DBH, volume of wood) was the main factor that affected the wind resistance of the eucalyptus, followed by a material factor. The degree of wind damage of a single plant is closely related to the size of the vertical wood, and also has a strong correlation with the wood properties such as the fiber width, the Pilodyn value and the stress wave value. The correlation between the mechanical properties such as the basic density of the wood and the dry shrinkage, the physical mechanics (bending strength, the flexural modulus of bending, the shear strength of the line, the compressive strength of the smooth grain, etc.) and the anti-wind resistance of the eucalyptus urophylla can be seen to show that the correlation between the two is not significant, and the wind-hazard index is similar to that of the lignin and the heddle, The correlation between cellulose and hemicellulose was not significant (P0.05). From the correlation analysis, it was found that the anti-wind property of Eucalyptus globulus was not related to the physical and chemical composition of wood. The regression analysis and typical correlation analysis of 26 characters, such as growth, material property, physical mechanics, chemical composition and so on, found that the main influencing factors that affect the three factors of the tree trunk deformation are the height of the tree, the volume of the material, the diameter of the breast, the thickness of the bark, the fiber length, Dry shrinkage rate, tensile strength, tensile elastic modulus and total cellulose content. in which, the growth characteristics of the Eucalyptus globulus which have the greatest influence on the wind resistance of the eucalyptus are the tree height, the material product, the DBH, the second is the fiber length, the tensile strength, and the genetic diversity analysis and test material is 109 samples of the eight eucalyptus groups, A total of 107 SSR loci covering the whole genome were identified.55 neutral genomic SSRs revealed a high diversity of Eucalyptus globulus, and a total of 1116 alleles were detected, with an average of 20.3 alleles per point, a PIC of 0.35508-0.9489, an average of 0.771, and a site with a higher polymorphism. The mean value of HE is 0.718, which indicates that the height of Eucalyptus is heterozygous, the average of Fst is 0.066, the genetic differentiation among the groups is not significant, and the variance component of the inter-population variance in the molecular analysis of variance is only 1%, indicating that the genetic variation is mainly present in the population. The genetic background of the subpopulation in Australia was found to be different from the genetic distance analysis of Nei (1972). The population of Eucalyptus grandis has rich genetic diversity, and can be used for the breeding of wind-resistant strains and the genetic improvement of the gene library. The SSR-associated analysis of the resistance-related traits of Eucalyptus urophylla was obtained by using 107 SSR markers with a large difference in the medium-position frequency of two types of gene pools. There was a significant linkage with 26 SSR loci (P0.05), which could explain the growth and resistance to the phenotypic variation of 9.26% ~ 71.14%. Among the 26 associated sites, the rate of the ECeSSR235 site to the wind-hazard index was 71.14%, the lowest in the ECeSSR570 site was 9.26%, and the average interpretation rate was 36.27%. The site ECeSSR332 was associated with four traits such as tree height, DBH, volume and wind-damage index, and the interpretation rate of the four traits was relatively high, over 60%. The site EUCSSR484, EUCSSR352, EUCSSR570 and EUCSSR422 were associated with two traits, such as the high tree height and the wind hazard index, and the EUCSSR489 and EUCSSR114 sites were associated with 2 traits such as tree height and volume.
【学位授予单位】：中国林业科学研究院
【学位级别】：博士
【学位授予年份】：2017
【分类号】：S792.39
，
本文编号：2511907
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