本文選題：日本落葉松　切入點：群體結(jié)構(gòu)　出處：《中國林業(yè)科學(xué)研究院》2016年博士論文　論文類型：學(xué)位論文

【摘要】：木材產(chǎn)量和品質(zhì)改良是林木育種研究的關(guān)鍵科學(xué)問題,木材形成是一個多基因控制的復(fù)雜過程,深入解析木材形成的關(guān)鍵因子和調(diào)控機理,有助于借助分子設(shè)計手段加快育種進程。日本落葉松(Larix kaempferi)是我國東北、華北和西南亞高山地區(qū)的重要針葉造林樹種之一,也是我國主要針葉紙漿材用樹種。本研究以17年生日本落葉松種源/家系試驗林為研究對象,選取具有代表性的603個基因型個體建立關(guān)聯(lián)群體,在分析表型多樣性、遺傳多樣性、核苷酸多樣性及連鎖不平衡水平基礎(chǔ)上,開展100個SNP標記和20對SSR標記與21個生長、形質(zhì)、木材纖維及木材化學(xué)等表型性狀的關(guān)聯(lián)研究,旨在篩選出與木材生長和品質(zhì)相關(guān)聯(lián)的功能標記,為日本落葉松分子設(shè)計育種和標記輔助育種奠定基礎(chǔ)。主要研究結(jié)論如下:1、日本落葉松關(guān)聯(lián)群體表型多樣性分析顯示:日本落葉松具有豐富的表型變異,表型變異系數(shù)為3.08%-54.84%,不同性狀的表型變異大小為:生長性狀纖維性狀形質(zhì)性狀木材化學(xué)性狀。關(guān)聯(lián)群體各性狀間及與地理環(huán)境因子間的相關(guān)性分析共檢測到134對顯著或極顯著正負相關(guān)關(guān)系。主成分分析有效驗證了性狀間的相關(guān)性,并將21個表型性狀降維成10個主成分。關(guān)聯(lián)群體中6個自然群體的表型方差分析顯示,除冠幅和早晚材微纖絲角的群體間差異不顯著外,其他性狀均存在顯著或極顯著差異;表型變異系數(shù)及表型分化系數(shù)分析表明日本落葉松自然群體具有豐富的表型變異;表型性狀聚類分析將6個自然群體劃分為兩個類群。關(guān)聯(lián)群體和人工群體表型性狀的比較分析顯示,大部分表型性狀平均值均較自然群體顯著提高,但部分木材纖維性狀(如晚材纖維長和纖維長寬比等)平均值反而降低。2、生長及材性相關(guān)基因的SNP分析表明日本落葉松具有較高的核苷酸多樣性水平。在擴增的27301 bp序列中共發(fā)現(xiàn)1698個SNP位點,SNP發(fā)生頻率為1/16;總核苷酸多樣性水平θw和πT變化范圍分別為0.0035-0.2167和0.00224-0.03045。中性檢驗結(jié)果表明大部分候選基因在進化過程中主要受純化選擇作用。進一步的LD分析顯示對日本落葉松開展基于候選基因的關(guān)聯(lián)研究是可行的。20個候選基因中僅有Lac2和AE2基因在1500 bp時,R2值才降至0.1以下,其余18個基因的LD在R20.1,核苷酸序列長度約為250 bp-1000bp時就已消失。定量PCR分析表明20個生長及材性相關(guān)基因在日本落葉松根、成熟木質(zhì)部、未成熟木質(zhì)部、形成層、韌皮部和葉片等6個組織均有表達,其中生長相關(guān)基因在成熟葉片表達量最高,材性相關(guān)基因在成熟木質(zhì)部和未成熟木質(zhì)部高表達。3、利用SSR和SNP標記對日本落葉松自然群體進行遺傳多樣性分析,鑒于日本落葉松本身的生物學(xué)特性(物候差異、花粉流和種子流)、分布區(qū)域的復(fù)雜地形變化及生境片段化影響,日本落葉松在針葉樹種中具有中等水平的遺傳多樣性(He=0.626);人工群體遺傳多樣性分析顯示經(jīng)過高強度的生長性狀人工選擇后,子代依然保存著較高的遺傳多樣性(He=0.613)。分子方差和遺傳分化系數(shù)分析表明日本落葉松遺傳變異主要以群體內(nèi)變異為主(遺傳距離:0.05-0.093)�；赟SR、SNP和SSR+SNP的自然群體遺傳結(jié)構(gòu)分析可將6個自然群體劃分為2個類群。以自然群體結(jié)構(gòu)劃分結(jié)果為基礎(chǔ),采用SSR+SNP的標記組合可將關(guān)聯(lián)群體劃分為2個類群。類群Ⅰ主要由草津和淺間等自然群體構(gòu)成,類群Ⅱ主要由富士和日光等自然群體及部分人工群體構(gòu)成。4、以關(guān)聯(lián)群體的遺傳結(jié)構(gòu)矩陣(Q矩陣)和親緣關(guān)系矩陣(K矩陣)作為協(xié)變量,采用MLM模型進行關(guān)聯(lián)研究。20個SSR位點中只有BC241與3年生胸徑和材積顯著關(guān)聯(lián)。在20個生長及材性相關(guān)基因的100個候選SNP中,共檢測到25個SNP位點與19個表型性狀顯著關(guān)聯(lián),對表型性狀的解釋率為1.09%-4.75%。生長相關(guān)基因中共有10個SNP位點與13個表型性狀顯著關(guān)聯(lián),其中AE基因家族中的AE2和AE3基因與部分形質(zhì)性狀和木材纖維性狀顯著關(guān)聯(lián)。10個木材性狀相關(guān)基因中,共檢測到12個SNP位點與12個表型性狀顯著關(guān)聯(lián),對表型性狀的解釋率為1.09%-4.75%。轉(zhuǎn)錄及調(diào)控因子中,mi R397a有1個位點與早材微纖絲角和4個晚材性狀(晚材壁腔比、晚材纖維長、晚材纖維寬和晚材率)顯著關(guān)聯(lián);MYB轉(zhuǎn)錄因子中有兩個位點(MYB1-337和MYB1-392)與密度顯著關(guān)聯(lián)。20個候選基因中,AE2、AE3和POD等3個基因與生長、形質(zhì)、早晚材纖維性狀和木材化學(xué)性狀均顯著關(guān)聯(lián),可作為木材性狀改良的重點關(guān)注對象;MIR397a、CESA2和CSL基因主要與晚材發(fā)育顯著相關(guān),可作為晚材性狀改良的重要標記;MYB轉(zhuǎn)錄因子主要與密度顯著關(guān)聯(lián),是進行密度改良的重要標記。
[Abstract]:Yield and quality improvement of wood is the key scientific issues of forest breeding, wood formation is a complex process control more than one gene, the key factor and the regulation mechanism of wood formation in-depth analysis, help to speed up the breeding process by means of molecular design. Japanese Larch (Larix kaempferi) is in the northeast of China, one of the most important coniferous species north and South West Mountain area, is also the main coniferous pulpwood in China with tree species. In this study 17 years of Japanese Larch provenance / family plantation as the research object, selects 603 representative base as individuals to establish related groups, in the analysis of phenotypic diversity, genetic diversity, nucleotide diversity and the level of linkage disequilibrium based on the development of 100 SNP markers and 20 SSR markers and 21 morphological, growth, association of wood fiber and wood chemical phenotypic traits, designed to filter out With the growth and quality of the wood functional marker, lay the foundation for the design of Japanese Larch molecular breeding and marker assisted breeding. The main conclusions are as follows: 1. The diversity of Japanese Larch populations association analysis showed that Japanese Larch had rich phenotypic variation, phenotypic variation coefficient is 3.08%-54.84%, the size of phenotypic variation in different traits: growth characters of fiber quality traits traits of wood chemical traits. The correlation analysis between the characters and related groups and geographic environmental factors were detected on 134 significant or extremely significant positive and negative correlation. Principal component analysis verified the correlation among traits, and 21 phenotypic traits of dimensionality reduction into 10 principal components of phenotypic variance 6. A group of natural population association analysis showed that except the crown width and earlywood microfibril angle difference between groups was not significant, other traits were significant or extremely Significant difference; phenotypic variation coefficient and phenotypic differentiation coefficient analysis showed that natural populations of Japanese Larch had rich phenotypic variation of phenotypic traits; cluster analysis of 6 natural populations were divided into two groups. Comparison analysis showed that the correlation group and artificial population phenotypic traits, some phenotypic traits were the average natural population increased significantly, but some wood fiber characteristics (such as wood fiber length and fiber length to width ratio) the average value of.2 decreased, the growth and material related gene SNP analysis showed that the nucleotide of Japanese Larch has higher diversity level. 1698 SNP loci in 27301 BP amplification of the SNP frequency is 1/16, the total nucleotide diversity; the level of W and theta PI T range were 0.0035-0.2167 and 0.00224-0.03045. neutral test results showed that most of these genes is mainly affected by purifying selection in evolution The role of LD. Further analysis showed that the development of Japanese Larch association studies of candidate genes based on Lac2 and AE2.20 are the only viable candidate genes in BP gene in 1500 when the R2 value was below 0.1, the remaining 18 of the LD gene in R20.1, nucleotide sequence length is about 250 bp-1000bp when it has quantitative disappear. PCR analysis showed that 20 genes related to growth and wood properties in Japanese Larch roots, mature xylem, immature xylem, cambium, phloem and leaf expression in 6 tissues, the expression of growth related genes in mature leaves was the highest material related genes in mature xylem and immature xylem of high expression of.3 and to analyze the genetic diversity of natural populations of Japanese Larch using SSR and SNP markers, in view of the biological characteristics of Japanese Larch itself (phenology, pollen flow and seed flow), distribution area of complex terrain And the effects of habitat fragmentation, genetic diversity of Japanese larch is in the middle level of the coniferous species (He=0.626); population genetic diversity analysis showed that after artificial artificial selection of high strength growth traits, the offspring still have high genetic diversity (He= 0.613). The molecular variance and the coefficient of genetic differentiation analysis showed that Japanese Larch genetic variation of the main body of group variation (genetic distance: 0.05-0.093). Based on the analysis of SSR, SNP and SSR+SNP in the natural population genetic structure of 6 natural populations can be divided into 2 groups. The natural group structure based on the results of using SSR+SNP markers can be divided into 2 groups of related groups. Group I consists of cyanazine and the shallow natural population composed of group II mainly by Fuji and sun and other natural populations and groups constitute part of the artificial.4, with genetic structure related groups Matrix (Q matrix) and relationship matrix (K matrix) as a covariate, using MLM model to study the correlation between.20 BC241 and SSR loci in only 3 years. Significant correlation between DBH and volume in the 100 candidate SNP 20 growth and material related genes, 25 SNP and 19 significant correlation between phenotypic traits were detected on phenotypic traits accounted for 1.09%-4.75%. of growth related genes in a total of 10 SNP loci and 13 phenotypic traits were significantly associated, which the AE family of genes AE2 and AE3 genes and some quality traits and wood fiber traits significantly associated.10 wood traits related genes, 12 SNP loci with 12 phenotypic traits significant correlation were detected on phenotypic traits accounted for 1.09%-4.75%. transcription and regulation factor, MI R397a 1 loci and earlywood microfibril angle and 4 latewood traits (latewood ratio of wall to cavity, late wood fiber length, latewood Fiber width and latewood percentage) was significantly associated with two sites; MYB transcription factors (MYB1-337 and MYB1-392) and density significantly associated candidate genes.20, AE2, AE3 and POD form 3 gene and growth traits and wood chemistry, early, late wood fiber traits were significantly correlated, as the focus of wood properties improvement the object of attention; MIR397a, CESA2 and CSL genes were significantly related to late wood development, can be used as an important marker of latewood trait improvement; MYB transcription factors significantly associated with density, is an important marker of density improvement.

【學(xué)位授予單位】：中國林業(yè)科學(xué)研究院
【學(xué)位級別】：博士
【學(xué)位授予年份】：2016
【分類號】：S791.223
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本文編號：1557315