【作者】 庄萍萍；

【导师】 郑有良； 魏育明；

【作者基本信息】 四川农业大学 ， 作物遗传育种， 2011， 博士

【摘要】 本文对来源于格鲁吉亚等14个国家(地区)的波斯小麦的蛋白质含量、农艺性状不同年份间的比较、农艺性状与蛋白质含量之间的关系等方面进行了深入分析,同时利用与功能相关的分子标记EST-SSR对来自14个国家(地区)的波斯小麦材料进行遗传多样性分析,以了解其群体遗传结构,分析群体间的遗传分化水平并探讨影响群体遗传分化的主要因素,从而为种质资源的评价、保护与合理利用提供客观依据,并为进一步发掘和利用其中有用的基因资源提供重要依据。主要研究结果如下：1.对80份波斯小麦从蛋白质含量分布情况、不同来源地材料的蛋白质含量变化、高分子量谷蛋白亚基与蛋白质含量关系等几方面进行了分析。结果表明,供试材料中蛋白质含量存在较大变异,变幅为7.71%-18.09%,平均值为13.88%；所有材料蛋白质含量方差分析表明,材料间差异显著,F=60.518**；比较不同来源地材料的表现,可以发现来自格鲁吉亚、前苏联、土耳其和加拿大各自内部的材料间存在极显著差异,而伊朗内部材料间差异不显著；基于蛋白质含量表现,采用类平均法,供试材料基于蛋白质含量的平均遗传距离2.41,所有材料被聚为四类。聚类结果也表明,依据蛋白质含量不能区分供试材料的来源。HMW-GS组成不同的小麦品种,其蛋白质含量明显不同。本研究筛选出了部分综合表现优异的材料,如蛋白质含量最高的PI532498和蛋白质含量最低但具有优质2*亚基的PI532510。2.对80份波斯小麦农艺性状不同年份间的表现进行了考察与分析,结果表明,各性状变异程度和幅度均较大。供试材料总体植株偏高,分蘖力强,以长穗型为主,小穗数和穗粒数较多,千粒重较低。株高、分蘖数、有效穗数、穗长、小穗数和穗粒数的方差分析结果表明：材料间存在极显著差异；年份间表现也呈极显著差异(F=29.44**)。对来自不同地区的材料间的农艺性状进行揭示了不同地区的材料有不同的优势性状。简单和偏相关分析中分别有22和7对性状达极显著相关。其中千粒重与蛋白质含量呈极显著负相关(r=-0.5908**)；揭示了千粒重较低的材料其蛋白质含量一般较高,穗长较长的材料其蛋白质含量较高。分蘖数、有效穗数和小穗数较多的材料其蛋白质含量也有增多的趋势、同时还对主要农艺性状与蛋白质含量进行了逐步回归分析、通径分析、主成分分析。逐步回归分析发现穗长对蛋白质含量的影响最大,通径分析发现,分蘖对数波斯小麦蛋白质含量的贡献最大。主成分分析表明,有五个主成分入选,其累积贡献率为85.09%,其中分蘖因子(因子1)贡献最大,贡献率为37.27%。3.利用普通小麦品种川农16与部分波斯小麦进行杂交。结果表明,杂种F1植株千粒重表现出了较大的超亲优势,抽穗期也较双亲大大缩短,同时杂种F1能够正常结实。波斯小麦中的优异基因资源可以通过直接杂交方式在普通小麦育种中利用。本研究的目的是为了将波斯小麦的有益性状引入普通小麦中,从而产生有益的变异。本试验中采取这种策略,表明也是有效的。4.利用14对EST-SSR引物对86份波斯小麦遗传多样性进行了分析。其中,共检测到32个等位变异,变幅从3-7个,平均每对引物检测到3.7个等位变异。群体遗传分析表明,不同位点的有效等位基因数、Shannon信息指数、期望杂合度和Wright固定指数等存在差异,同时各参数评价结果较为一致。分析表明,位点SWES179基因分化系数Fst值最小,为0.1535(FST=0.1535),说明在该位点上,其15.35%的遗传变异来自于群体间。各群体间的基因分化系数较大,但Nm值与Fst值刚好相反,大多数位点Nm值平均值小于1,除了位点SWES179的Nm值大于1,说明在该位点各种群已经固定。虽然各位点等位基因在供试材料中倾向于杂合表现,但群体的杂合子比例较低,不同位点间存在差异。Ewens-Watters on中性测验表明在所有位点出现的选择是趋向于群体内杂合,除了位点CAU12外在其余各群体内均位于95%置信区间之间,属于中立性位点。Ohta两位点分析指出各群体间存在有限的基因交流。同时群体内的连锁不平衡变异组分大于群体间。Hardy-Weinberg平衡的卡方和似然比测验均揭示了SWES18和SWES86在波斯小麦材料中处于平衡状态,其余所有位点处于非平衡状态。参试材料间平均遗传相似系数为0.9375,基于平均遗传相似系数(GS=0.6293)材料可被聚为五类,EST-SSR的聚类结果不能区分材料的地理来源。同时还可看出,EST-SSR可以有效的用于评价波斯小麦的群体遗传结构。更多还原

【Abstract】 The grain protein content, agronomic performance in different years, and the relationship between agronomic traits and protein content among 80 accessions of Triticum turgidum ssp. carthlicum from fourteen countries or areas, including Georgia, Turkey and so on, were investigated.. Moreover, the population genetic diversity based on EST-SSR markers was also estimated. These results might be useful for understanding the genetic structure and diversity of carhtlicum wheat (Persian wheat). Thus, it could provide important information for germplasm evaluation, conservation and reasonable utilization.The results were described as following:1. The grain protein contents of 80 persian wheat accessions were investigated. Higher variability for protein contents was observed, and the range of variation was 7.71%-18.09%, with the average of 13.88%. Based on analysis of variance (AVOVA), it was found that the genotype had significantly effects on the protein content (F= 60.518**). Comparing the performance of protein content of all materials from different source, it was found that the accessions from Georgia, the former Soviet union, Turkey and Canada had significant effects on each other. Whereas, no significant difference among the materials from Iran. According to the unweighted pair group with arithmetic average (UPGMA), based on the average genetic distance 2.41, the accessions could be clustered into 4 groups. Cluster analysis indicated that the materials from different origion could not be distinguished. The relationship between protein contents and high molecular weight glutenin subunits (HMW-GS) were studied also. The results showed that grain protein content of the materials with different subunits was different. According to the main characters, some accessions were screen out for one or some superior performance, such as PI532498 and PI532510 with the lowest protein content but with the superior quality subunit 2*.2. The agronomic traits of 80 carhtlicum wheat accessions collected from 14 countries or areas including Georgia, Turkey and so on were investigated based on analysis of variance. Higher variations of the nine agronomic traits were observed. The higher plant height, more spikelets and kernels per spike, lower 1000-grains weight and longer spike length were found in Persian wheat. The results suggested that the environment was important for the agronomic performance of wheat. Meanwhile, all the accessions, of which, the agronomic performance in different years and different origion, their difference among all the accessions. Based on analysis of variance (AVOVA), it was found that the genotype and year (F=29.44**) had significant effects on agronomic traits. The agronomic performance of the materials from different countries or areas showed that materials from different origion were with different superior traits. Besides, the agronomic traits and grain protein content were analyzed by correlation, stepwise regression, path, principal component. The correlation analysis indicated that 22 and 7 pairs of agronomic traits had significant effects in simple correlation and partial correlation, respectively. It was found that the negative significant correlation between 1000-grain weight and grain protein content was detected (r=-0.5908**). Lower 1000-grain weight could lead to higher grain protein content, while, longer spike length and more tiller number per plant, spike number per plant, spikelet number per spike might lead to higher grain protein content. Based on stepwise regression analysis, spike length make great contributes to grain protein content and based on path analysis, grain protein content was most affected by tiller number per plant. According to the principle elements analysis, five principle elements were obtained, which contributes variance over 85.09%, especially the tiller number type (37.27%).3. The hybrids between Chuannong 16 and some Persian wheat were carried-out. The 1000-grain weight was surpassing the parents, and heading date was much shorter than parents. The seeds were obtained in F1 generation. This experiment showed that the useful genes in Persian wheat could be tranfered into common wheat.4. Genetic diversity in 86 carthlicum accessions was investigated using EST-SSR markers. A total of 32 alleles were detected on 14 EST-SSR loci. At each locus, the number of alleles ranged from 3 to 7, with an average of 3.7. There were differences on the effective alleles, Shannon index, heterozygosity and wright fixation index among population. These results based on the different indexes were in consistence. Based on Nm analyzed, most of the average Nm was less than 1 except for locus SWES179 was more than 1, indicating that populations on this locus may inhibit the genetic differentiation. Wright fixation index indicated allelic prefer to heterozygosity performance, but the lower value of heterozygosity in carthlicum wheat was found, Ewens-Watterson tests of neutrality revealed that the high level of genetic diversity within loci was maintained by heterozygosity selection. Except for locus CAU12, all the loci were located in 95% confidence, belonging to neutrality site. Ohta’s two-locus analysis suggested there was limited migration among populations. The variance of linkage disequilibrium within population was higher on than that between populations. Selection and migration could lead to all detected loci except SWES18 and SWES86 of triticum carthlicum showed no Hardy-Weinberg equilibrium. The largest genetic similarity (GS) value was 0.9375. On the average GS of 0.6293,86 carthlicum accessions could be custered into five groups. The clustering results had no necessary connection with material origin. The consequence also indicated that the evaluation using in EST-SSR marker was available for Persian wheat genetic structure and diversity.更多还原