为挖掘野生大豆优异稀有基因,2006年至今以栽培大豆绥农14(轮回亲本)与野生大豆ZYD00006(供体亲本)为双亲材料,经杂交、回交,标记辅助选择构建获得一套覆盖野生大豆全基因组的染色体片段导入系(代换系).该群体共192个株系,包含野生大豆目标导入片段237个,平均每个连锁群的导入片段个数为11.85个;导入片段总长度1865.17 cM,覆盖整个基因组的82.43％.其中L连锁群野生大豆基因组覆盖率最高,为100％,N连锁群覆盖最低为53.17％.最长导入片段43.30 cM,最短导入片段0.22 cM.高度一致的遗传背景对大豆重要基因及野生大豆特有优异基因挖掘具有重要意义.同时,野生资源的引入极大丰富了栽培大豆的遗传基础,进而使得导入系后代表型变异丰富,为大豆遗传育种提供重要的材料基础.

为了培育高蛋白栽培大豆,大豆高蛋白质含量一直是大豆品质育种的重要研究方向.大豆蛋白质含量受遗传效应影响较高且由多基因控制,对其相关位点进行深入研究具有重要的理论意义和应用价值.本研究利用栽培大豆‘绥农14’作为轮回亲本,野生大豆ZYD00006作为供体亲本构建了野生大豆染色体片段代换系(chromosome segment substitution lines,CSSL),在2014年和2015年这两年间共检测到21个与大豆子粒蛋白质含量相关的QTL.其中2014年在GM20连锁群上加性效应值变化范围为1.51～2.18,在2015年加性效应值变化范围为2.13～2.66.在上述初步定位的基础上,我们构建了三套残留杂合株系(residual heterozygous line,RHL)群体,对不同的杂合区间进行了筛选,并以此为基础进行精细定位,定位到控制大豆子粒蛋白性状的GM20染色体处约9.13～9.98 Mb处.同初步定位结果相比,将QTL区间由12.3 Mb精细定位到852kb.我们对该区段15个基因进行注释,研究发现Glyma20g07060、Glyma20g07280作为关键候选基因,可能与控制大豆子粒蛋白质性状含量相关.上述研究结果为大豆蛋白质含量QTL精细定位研究提供了材料支持,关键候选基因的发现为进一步提高大豆蛋白质的含量提供了数据参考.

To study the QTL mapping of seed weight per plant,which is beneficial to increase the yield of soybean.In this study,the BC3 F3 population is a chromosome segment substitution lines which constituted by 161 lines,with the wild soybean ZYD00006 as donor parent and the cultivar Suinong 14 as recurrent parent,selfing and backcross continuously for several years.The genetic background of this population relatively consistent,which reducing the interference greatly and improving the accuracy of QTL mapping.The QTL mapping was combined by ANOVA Method and T-test for independent samples.A total of 9 QTLs underlying seed weight per plant were detected which distributed on 7 linkage groups.Three QTLs were detected by both methods,including QSW-J-1,QSW-J-2,QSW-G-1.2 QTL were in accord with known results.Another 7 ones were the new discovery QTL,which should be specific loci in our materias.The fragment length of QSW-J-1 was 7.0 cM,and the additive effects of it is-2.7 g,which could be used as the first choice loci for further study.

利用野生大豆ZYD00006和栽培大豆绥农14所构建的回交导入系群体BC3F3代为研究材料,选择亲本间存在差异的121个SSR标记对114个株行材料进行基因型分析;利用T测验对含野生大豆纯合双导入位点(即B-B位点组合)植株表型值与绥农14表型值进行检测,以P≤0.05作为阈值,共获得104对B-B位点对表型影响显著,再经T测验,28对互作位点存在上位性效应,其中正向上位性效应位点10对,负向上位性效应位点18对,本研究结果揭示了上位性效应对大豆蛋白质含量性状的重要影响,同时这些位点信息将为大豆高蛋白分子辅助育种研究提供重要的理论基础.

A soybean backcross population was constructed using Suinong 14(recurrent parent)and wild soy-bean ZYD00006(donor parent). 23 QTLs(4 with positive effects,19 with negative effects)for oil content on 11 linkage groups were detected by One - way ANOVA at 0. 01 level. Compared with recurrent parent Suinong 14,13 BC3 F3 lines had higher oil contents and 20 BC3 F3 lines had lower oil contents. These 33 lines were selected to con-struct a selective population. Based on this selective population and random population(control),25 QTLs for oil content on 15 linkage groups were found by Chi - square on genetic hitchhiking,among them 11 QTLs had positive effects,and 14 QTLs had negative effects. Total 34 QTLs were found by these 2 methods. Among them,14 were detected in both methods,and 11 were newly found.

Mutate gene coding sequence is a key approach to detect the function of special gene. Triparental mating is an efficient method to mutate specific gene, which allows the foreign DNA enter into the receptor cell using the bacterial conjugation character. Then the target gene could be replaced by foreign DNA via homology crossing. Some factors could influence the efficiency of triparental mating, such as the length of the homologous arms, and the ratio of mixture bacteria (donor stain, helper strain and recipient strain). In this study, we want to promote the efficiency of triparental mating procedure by test the effect of homologous arms and ratio of mixture bacteria. The coding sequence of typeⅢeffector nopB, nopC, nopL in Sinorhizobium fredii HH103 were mutated to detect the effect of homologous arm's length and the ratio of mixture bacteria. We demonstrate that homologous arm's length of about 521 bp and 861 bp were the most efficiency length, and the ratio of 2:1:1 (rhizobium:helper:donor) was the highest efficiency ratio. Our results supply a modified and high efficiency ratio. Our results supply a modified and high efficiency protocol for the gene mutate in gram-negative bacteria.