【作者】 陈峥峥；

【导师】 傅体华；

【作者基本信息】 四川农业大学 ， 分子生物学与生物化学， 2009， 硕士

【摘要】 簇毛麦（Dasypyrum villosum Candargy）是小麦的近缘属种,蕴藏着大量能改良小麦品种的优良基因。本研究以上世纪90年代西南地区大面积推广的普通小麦良种绵阳11（MY11）作为母本与簇毛麦杂交,然后回交两次再连续自交,并在早期世代辐射后连续自交到BC₂F₅世代获得后代种子35个,运用形态标记、分子细胞学标记与生化标记等多种方法对其遗传基础进行鉴定。其研究结果如下:1.细胞学结果表明:在对35个材料进行根尖染色体观察后发现,35个材料中,染色体变化范围为41至43,128-3、128-4、128-6和131-1四个材料染色体数目为41,135-2和139-2两个材料染色体数目为43其余材料染色体数目为42。对35个材料进一步进行花粉母细胞染色体行为观察发现,材料135-2,139-2在减数分裂过程中没有多价体的形成,由此可以推断两个材料中附加的一条染色体为簇毛麦染色体。而材料130-2在染色体减数分裂过程中出现了三价体和多价体,说明其可能由于簇毛麦染色体通过易位或者小片段插入的方式导入了MY11染色体组中。而材料128-4、129-1、129-3、129-6、131-4、133-4、132-2、136-2、137-3、137-4、138-1和139-1等十二个材料的平均单价体数不超过0.4个,且没有多价体存在,相对紊乱系数不超过0.02,表现出一定的细胞学稳定性。2.对该35个材料进行农艺性状考察发现:35个材料株高从86cm至124cm不等,全部高于亲本之一的绵阳11的81.6cm,存在明显的遗传差异。同株高一样,分蘖数和稳长在单株之间也存在十分明显的性状分离现象,这些性状差异说明可能影响普通小麦株高、穗长、分蘖数的簇毛麦基因导入了绵阳11,而后代存在大幅度的遗传变异,也可以大大增加我们选择的范围。3.以簇毛麦总基因组DNA标记探针,中国春总基因组DNA为封阻对材料133-4、135-2进行基因组原位杂交分析,结果显示材料133-4染色体末端显示出黄绿色的杂交信号,综合细胞学结果得出133-4是一个稳定的小片段异附加材料;材料135-2染色体组有一条染色体显示出杂交信号表明135-2是一个单体异附加材料。4.以绵阳11、中国春、簇毛麦作为对照,利用SDS-PAGE对稳定的材料进行分析,结果表明131-4、138-2、128-4、139-4、133-3、137-3、136-2等7个材料的亚基组成和亲本绵阳11完全一致为1,7+8,5+10;137-4,133-4,138-1三个材料的亚基组成出现变异为1,7,5+10;还有材料129-6则出现了1条两个亲本都不存在的条带,结合农艺性状结果说明出现变异的三个材料导入了簇毛麦遗传物质。更多还原

【Abstract】 Dasypyrum villosum is the relative genus of Triticum aestivum,which is an important source carrying fruitfully valuable genes for improving the common wheat.In this research,the Dasypyrum villosum was used to cross and bachcross with common wheat Mianyang11 released in southwest China in 20th century and the hybrid was backcross to MY11 2 times and then the backcrossed hybrid was selfed.The seeds of ealry gerenation were treated with 4000 roentgen ofγ-radiation.Of these progenies,35 seeds selected from BC₂F₅ generation were identified by morphology,cytology,GISH and SDS-PAGE.The main results are as follows:1.Cytological analysesChromosomal number of 35 materials counted at mitosis in root tip meristems ranged from 41 to 43,the Chromosome number of 128-3、128-4、128-6 and 131-1 is 41,the Chromosomal number of 135-2 and 139-2 is 43,and the number of rest materials is 42.The examination of pollen mother cells showed that no trivalent chromosome and multivalent has been found in 135-2 and 139-2 suggesting that one Dasypyrum’s chromosomel might be added into 135-2 and 139-2,However the trivalent chromosome and multivalent were found in 130-2,andthe 12 materials including 128-4、129-1、129-3、129-6、131-4、133-4、132-2、136-2、137-3、137-4、138-1 and139-1 only have bivalent,which suggested these 12 materials might be stable.2.Agronomy characteristics analysesThe height of 35 materials ranged from 86cm to 124 cm,and all of them are higher than Mianyang 11.the other charctors,such as the length of ear the number of tillering exited charcters segregationr.This variation of the agronomic character showed that the gene of Dasypyrum villosum might have been transferred into the Mianyang11. 3.GISH analysesGISH was carried ou using the genomic DNA of Dasypyrum villosum as the probe and the genomic DNA of Triticum aesitvum var,"Chinese Spring"as the blocking.The results demonstrated that 135-2（2n=43） has a signal at one chromosomal,and it might be an alien additonal material,while 133-4（2n=42） might be a small fragment translocation material.4.SDS-PAGE analysesHigh molecular weigt glutenin subunit comprosition of the stable materials was analyzed by SDS-PAGE.Chinese Spring（subunit:null,7+8,2+12）,Mianyang11 （subunit:1,7+8,5+12）,and Dasypyrum villosum were used as contrasts.The results indicated that most the subunit comprosition of 7 materials studied were as same as the Mianyang11 （1,7+8,5+12）,and that of the materials of 137-4,133-4 and 138-1 were 1,7,5+10.Further more,the material of 129-6 had a band which has not exited in any parents.更多还原