栽培二粒小麦农艺性状与贮藏蛋白分析

1、栽培二粒小麦农艺性状与贮藏蛋白分析硕 士 生： 王晓蓉导 师： 郑有良 教授摘 要 栽培二粒小麦是小麦属二粒系的一个四倍体带皮栽培种（2n=4x=28, AABB），具有早熟、抗病和高蛋白等优良特性，是普通小麦遗传改良的重要基因资源。本研究对91份栽培二粒小麦的主要农艺性状及贮藏蛋白进行了评价与分析。主要结果如下：1. 农艺性状分析表明，栽培二粒小麦存在丰富的变异，具有植株较高、分蘖力强，穗粒数和千粒重偏低，抽穗期和生育期较长等特点。相关分析表明，株高与穗长、生育期，有效穗与抽穗期，穗长与小穗数、穗粒数，小穗数与穗粒数，穗粒数与生育期，以及抽穗期与生育期间呈极显著相关和偏相关。主成分分析中，4

2、个主成分因子（抽穗期、穗长、有效穗及粒重）累积贡献率达88.16%，其中抽穗期因子的贡献率最大（38.12%）。所有供试材料在遗传距离0.50 水平上聚为四类，其中类I为高秆大穗晚熟型，类II为高秆少分蘖晚熟型，类III为矮秆粒多早熟型，类IV为粒多强分蘖早熟型。大多数来源地相同的材料被聚在不同类中，表明栽培二粒小麦农艺性状表现与其地理来源间不存在必然联系。2. 利用A-PAGE对栽培二粒小麦醇溶蛋白等位变异进行了分析。结果表明，栽培二粒小麦在醇溶蛋白位点上具有丰富的遗传多样性。91份材料共分离出58条迁移率不同的谱带和84种带型，每份材料可分离出431条带，平均17条，其带型多态性为92%。

3、供试材料间遗传相似系数（GS）变幅为0.431-1.000，平均为0.645。其中区域内平均GS最大的是亚洲（0.735），最小的是北美洲（0.652），而区域间平均GS最小的是北美洲与欧洲（0.627），最大的是北美洲与亚洲（0.700）。供试材料在GS值0.650水平上被聚为3类，且多数来源地相同的材料趋向于聚为一类，表明醇溶蛋白聚类结果与材料的地理来源有一定的相关性。3利用SDS-PAGE 技术对栽培二粒小麦高分子量麦谷蛋白亚基进行了检测。结果表明，供试材料中共有13种亚基类型和24种组合类型。在Glu-A1位点，null亚基分布频率最高（47.3%），1亚基次之（25.3%），有8份材

4、料具有2*优质亚基。在Glu-B1位点，7+8亚基比例最高（35.2%），另分别有5份材料具有优质亚基13+16和14+15。栽培二粒小麦中，（null，7+8）为出现频率最高的亚基组合，同时也具有与小麦品质正相关的亚基组合（1，7+8），（2*，7+8）以及（1，13+16）。4. 利用3对Glu-A3位点和2对 Glu-B3位点低分子量麦谷蛋白特异性引物对87份供试材料进行分子标记检测。结果表明，在栽培二粒小麦中分别存在N-端为ISQQQ-、MDTSCIP-、MENSHIP-、METSHIP-和METSCI-的LMW-GS类型，且具有长度多态性。其中Glu-3A.1 和Glu-3B.2位点

5、在供试材料中具有3种等位变异，而其它位点均只有2种。Glu-3A.2、Glu-3A.3、Glu-3B.1和Glu-3B.2位点的优势优势等位变异分别为680bp、500bp、500bp和450bp的片段，频率则依次为91.9%、94.2%、85%和86.2%。而Glu-3A.1 位点优势等位变异为450 bp和600bp的2 片段，频率为80.4%。结果还表明，来源于欧洲的材料存在较多的LMW-GS多态性。关键词：栽培二粒小麦；农艺性状；醇溶蛋白；高分子量麦谷蛋白；低分子量麦谷蛋白；分子标记Agronomic performance and seed storage protein analy

6、sis in Triticum dicoccum Schrank Wang Xiao-rongDirected by Prof. Zheng You-liangAbstract Cultivated emmer wheat (Triticum. dicoccum Schrank), a primitive hulled wheat, is an allopolyploid species with the genome formula AABB. It has been reported to be important for the improvement of bread wheat, b

7、ecause of some valuable characters，such as harvest earlier, high protein content, good resistance to stem rust, bunt and powdery mildew. In order to exploit germplasm resources with desirable traits, the main agronomic characters and genetic variations of storage proteins were evaluated. The results

8、 were described as follows:1. The agronomic characters of 91 cultivated emmer wheats were evaluated by variance, correlation, principal component and cluster analysis. Higher variation of the eight agronomic characters was observed among all accessions. The result of correlation analysis indicated t

9、hat there were significant positively relationships between spike length, growing period and plant height, and significant negative relationships between number of productive panicles and heading time. Four main components, which made the contribution of 88.16%, were obtained based on principal comp

10、onent analysis, especially the number of grains per spike component was the highest value (38.12%). Furthermore, all materials were clustered into four groups at the level of 0.50 genetic distance (GD) value. In addition, most accessions from the same origins were clustered into different groups, in

11、dicating that there was no direct relationship between genetic divergence and geographical origins.2. Genetic variations of gliadins among 91 emmer accessions were investigated by A-PAGE. Higher genetic variability was detected. A total of 58 gliadin bands and 84 gliadin patterns were obtained. The

12、number of bands presented in these accessions varied from 4 to 31, with an average of 17. The coefficients of genetic similarity ranged from 0.431 to 1.000, with the average of 0.645. The GS index within the accessions from Asia was the highest (0.735), while the lowest GS index (0.652) was obtained

13、 within North America. All T. dicoccum accessions were clustered into 3 groups at the level of 0.650 genetic similarity value. Most accessions from the same origins were clustered into the same group, showed that the genetic relationship in T. dicoccum accessions based on gliadins were associated wi

14、th its geographical distribution.3. A total of 13 HMW-GS subunits and 24 combinations were observed in cultivated emmer wheat by SDS-PAGE. Four and nine alleles were identified at Glu-A1 and Glu-B1 loci, respectively. At the Glu-A1 locus, the subunit null had the most frequent (47.3 %), followed by

15、subunit 1 (25.3%). The subunit 2*, which was superior to subunit 1, were detected in 8 accessions. At the Glu-B1 locus, subunits 7+8 were the main type (35.2%). Subunits 13+16 and 14+15, which were associated with good quality, were observed in 5 accessions, respectively. The subunits (null, 7+8) we

16、re identified as the dominance combination. Some rare combinations, which related to good quality, such as (1,7+8), (1,13+16), (2*,7+8), were also detected.4. The allele variation of Glu-A3 and Glu-B3 loci in T. dicoccum were detected by 5 specific LMW-GS primers. The results showed that there were

17、5 groups of LMW-GS genes based on deduced amino acid sequence of N-terminal domain, including ISQQQ-、MDTSCIP-、MENSHIP-、METSHIP-and METSCI-, and confirmed that the primer pairs were specific for the corresponding LMW-GS type separately. There were length polymorphisms in all sequences of LMW-GS type.There were 3 LMW-GS genes at Glu-3A.1 and Glu-3B.2, respectively, and the others were identified 2 LMW-GS. The dominant alleles were 680bp at Glu-3A.2 locus, 500bp at Glu-3A.3 locus, 500bp at Glu-