【作者】 邓世民；

【导师】 刘树兵； 王洪刚；

【作者基本信息】 山东农业大学 ， 作物遗传育种， 2008， 硕士

【摘要】 本研究以普通小麦品种莱州953、六倍体人工合成小麦Am3(波斯小麦×粗山羊草)、8个从莱州953(受体)/Am3杂交组合的BC4F4代选出的导入系,以及其中2个导入系(IL15、IL16)与莱州953杂交获得的F2群体及F3家系为材料,进行了4个产量相关性状的调查分析、导入片段的检测及产量相关性状主效QTLs的作图,主要获得以下结果:1、利用957对小麦SSR引物对供体Am3与轮回亲本莱州953进行了多态性检测,结果有793对引物能在莱州953和Am3中扩增出稳定的带型,241对引物在莱州953和Am3之间揭示多态性,多态性引物的频率为30.4%。有132对引物能被准确定位在染色体的具体位置上。其中有72对引物在8个导入系中检测到了Am3的片段。共检测到115个Am3片段,平均长度为11.4cM,共覆盖基因组11.4%。导入系中导入的片段最高的为IL-21,含27个供体片段;最低的为IL-17,有7个供体片段。各导入系中导入片段的平均长度最高的为IL-21,平均长度为17.6cM。最低的为IL-20,平均长度为9.55cM。供体片段覆盖基因组的比例最高的为IL-21,占25.3%;最低的为IL-17和IL20,占5.2%。2、对莱州953与2个导入系(IL-15、IL-16)的单株穗数、穗长、小穗数、穗粒数4个性状进行了调查。结果表明,2个导入系4个性状的表现与莱州953相比均达到了极显著水平。与莱州953相比它们主要表现为穗长变短,穗粒数减少,小穗数减少,但单株有效穗数明显增加。相关分析表明4个性状的表型值之间存在高度相关(0.57-0.72),单株穗数与其它3个性状(穗长、小穗数、穗粒数)存在明显的负相关(-0.57~-0.71)。3、根据对亲本的调查结果,对导入系IL-15、IL-16与莱州953杂交的F2及F3家系单株穗数、穗长、小穗数、穗粒数进行了调查分析。结果发现,4个性状在分离群体中呈现明显的分离,其中在IL-16/莱州953分离群体中,4个性状都呈现较明显的双峰分布。根据该群体4个产量相关性状都呈双峰分布的特点,对该群体的性状划分为莱州953和IL-16两种类型,并根据F3株系的性状表现进行了F2基因型的推导。对4个性状在F2分离群体中分离规律进行分析。χ2检验表明:4个性状的分离都符合3:1的分离比例。以上结果表明,在导入系IL-16中,已将控制单株穗数、穗长、小穗数、穗粒数的QTLs分解开来,将由多基因控制的数量性状位点,变成了由单个的孟德尔遗传因子控制的质量性状位点,从而可以将其作为质量性状基因进行定位。4、利用IL-16/莱州953 F2群体中在4个性状上表现两种极端类型的单株,通过检测各多态性引物的分离结果与性状之间的关系,初步找到3个SSR标记Xgwm513、Xwmc657、Xgwm495与4个性状位点连锁。利用IL16/莱州953分离群体的基因型数据建立了连锁图,3个标记之间遗传距离分别为10.12,6.47cM,连锁群长度总共16.59 cM。为进一步确定控制这些性状的QTLs与这3个标记间的连锁关系,以该连锁群为基础,利用Zhu et al.(2007)提出的F2:3家系分析模型及计算软件对该群体的F2、F3表型数据进行分析,结果表明,控制这4个性状的QTL位点均位于标记Xwmc657、Xgwm495之间,在12.9cM处。因此,确定控制单株穗数、穗长、小穗数、穗粒数这4个性状的QTLs位于同一位点。并将此4个位点暂命名为Qsl-am3、Qspp-am3、Qgps-am3、Qspi-am3。在此基础上,绘出该连锁群的连锁图。该区间与Somer et al. (2004)发表的小麦SSR连锁图一致,位于4B染色体长臂近着丝粒位置。更多还原

【Abstract】 Common wheat genotype Laizhou953, wheat genotype Am3 synthesized by crossing Triticum carthlicum (AABB) with Aegilops tauschii (DD), 8 intro -gression lines (ILs) derived from the BC4F4 generation of Laizhou (recurrent parent)/Am3, 2 F2 populations using the 2 introgression lines (IL15, IL16) to cross with Laizhou953 and the F3 families were used as materials to carried out SSR detection of the introgressed donor segments, investigation of 4 traits related to yield, and mapping of major QTLs (quantitative trait loci) related to yield. Results were obtained as below:1. 957 pairs of wheat SSR markers were used to detected polymorphism between Laizhou953 and Am3, in which 793 pairs of them amplified stable PCR products and 241 pairs showed polymorphism between the two parents, the frequency of polymorphic markers was 30.4%. Among the polymorphic markers, 83 markers were located on the linkage groups and 72 of them detect -ed introgressed segements of Am3 in the 8 introgression lines. Totally,115 donor segements with average length of 11.4 cM, covering 11.4% of the total of genome were detected. Among 8 introgression lines, IL21 had the most introgression segements of 27, while IL17 were the least of 7, respectively. IL21 had the longestest ingression segements with average length of 17.6cM, while IL-20 was the shortest with the length of 9.55 cM. IL-21 showed the highest coverage of donor introgression (25.3%), while IL17 and IL20 were the lowest (5.2%).2. Four traits, the spikes per plant, spike length, grains number per spike, spikelets of Laizhou 953 and 2 introgression lines were investigated. The results showed that the 4 traits of the 2 introgression lines had significant difference from Laizhou953. Compared with Laizhou953, the two introgre ssion lines showed shorter spike length, fewer grains number per spike and spikelets, but more spikes per plant. Correlation analysis indicated that the performance value of 4 traits showed high correlation (0.57~0.72), spikes per plant and other 3 traits had an obvious negative correlation (-0.57~-0.71).3. The spikes per plant, spike length, grains number per spike and spike -lets of IL15/Laizhou953 and IL16/Laizhou953 F2 and F3 families were investi -gated. The results showed that 4 traits segregated significantly, in the popula -tion of IL16/Laizhou953, 4 traits had shown a clear bimodal distri bution. According to the traits of F3 families we deduced the corre spon ding F2 genetype, and analyzed the segregation of F2 populations.χ2 (Chi square) tests showed that 4 traits segregate according to the 3:1 ratio which indicated that QTLs of 4 traits have been dissected into single Mendelian factor and can be mapped as qualitative trait loci in this population.4. Two extreme types of individual plants of 4 traits in the population were used to study the relationship between the introgressed donor segment and phenotype. It was showed that 3 SSR makers Xgwm513, Xwmc657 and Xgwm495 located on 4B showed high correlation with 4 traits and were run across the population. A linkage group was constructed with a total genetic distance of 16.59 cM. A F2:3 model and software proposed by Zhu et al. (2007) was used to analyze the phenotype data of this population to ascertain the position of the QTLs in this linkage group, and the four QTLs were all located to the position of 12.9 cM in this linkage group between marker Xwmc657 and Xgwm495. Therefore, the four QTLs designed as Qspp-am3, Qsl-am3, Qspi-am3, Qgps-am3 were controlled by one locus. The linkage of this region was constructed which was coincide with the 4B linkage map of Somer et al. (2004). Mapping of the QTLs related to yield as Mendalian factors lay a foundation for the fine mapping of this region for the map-based cloning and marker assist selection in breeding program.更多还原