【作者】 盛万民；

【导师】 王凤义；

【作者基本信息】 东北农业大学 ， 作物遗传育种， 2009， 博士

【摘要】 马铃薯栽培种的遗传基础狭窄是阻碍其品种改良至关重要的限制因子,已为各国的育种实践所证实。然而,幸运的是还有丰富的马铃薯近缘栽培种和马铃薯野生种的存在,它们是改良现有品种潜在的种质资源,并已逐步在马铃薯育种实践中应用。马铃薯野生种Solanum demissum作为重要的晚疫病抗性资源已为一些育种家所应用,并取得了较好的育种效果。该野生种为六倍体种,原产于墨西哥。目前在世界范围内,含有该野生种血缘的育成品种已有200多个。该野生种除了高抗晚疫病外,还具有抗癌肿病、抗疮痂病,抗PVY、抗PVA、抗PLRV、抗马铃薯甲虫、以及高淀粉和高蛋白质含量等有利性状。以往的育种实践表明,以该野生种为母本易与栽培品种杂交,其杂种后代再与栽培种回交2~3次,能有效地将结薯多、比重高等丰产性状逐渐转入栽培品种,有效改良马铃薯的产量性状。然而,利用野生种来改良栽培种是一个周期较长的过程,如何能在较短的时间内取得良好的改良效果、提高育种效率一直是育种家所关注的。本试验研究采用三种交配设计模式,配制了种间杂交和回交组合40个,旨在探索马铃薯种间杂种回交群体的改良效果,探求有效克服野生习性的方法、优化种间杂交育种的程序和提高育种效率的途径。其最终目的是加速马铃薯种间杂种的改良进程,提高野生种在栽培品种改良上的利用效果。试验结果表明,对杂种群体进行回交可大幅度削弱野生种与栽培种性状间的连锁与互作。为此,利用马铃薯野生种Solanum demissum资源不会遇到性状重组的障碍。在种间杂种和各回交群体世代中,某些性状间存在动态相关关系,表明基于不同世代的相关系数间不可混用,否则可能引出错误的结论。采用配合力分析的方法,对利用普通栽培品种的早熟性直接克服种间杂种群体匍匐茎长、结薯晚等野生性状的试验结果表明,栽培品种在平均单薯重、商品薯率、匍匐茎长度等性状上存在着极显著差异,在单株产量、单株结薯数、生育期、比重、蛋白质含量、Vc含量、还原糖含量等性状上存在显著差异;种间杂种群体在主茎数、茎粗、商品薯率、蛋白质含量等性状上存在极显著差异,在单株产量、单株结薯数、平均单薯重、匍匐茎长度、生育期、比重、还原糖含量等性状上存在显著差异;双亲互作效应仅在块茎比重上表现为极显著差异。配合力效应估算结果表明,同一性状的一般配合力效应值在不同亲本间差异较大,并且同一性状的特殊配合力效应值在不同组合间差异亦较大。本试验结果还表明,栽培种的早熟性能有效地克服马铃薯野生种Solanum demissum所具有的匍匐茎长、结薯晚等野生性状。应用细胞遗传效应分析方法,对正反交两种组配类型的回交一代群体的遗传参数的分析结果表明,亲本的细胞质效应、组合的细胞核效应及质核互作效应均对后代群体有显著的遗传效应。亲本的细胞质遗传效应在所有测试性状上均表现出极显著的差异;组合的细胞核效应除在株高、主茎数、芽眼深度、比重等4个性状上不显著外,其他9个被测性状的差异均达极显著水平;组合的质核互作效应在株高、茎粗、单株产量、蛋白质含量等性状上存在显著差异,而在单株结薯数、还原糖含量、Vc含量等性状上存在极显著差异。同一性状的细胞质效应值在不同亲本间差异较大,并且同一性状的细胞核效应值和质核互作效应值在不同组合间差异亦较大。本试验结果还表明,亲本间正反交两种不同回交改良方式对后代群体主要农艺性的表现有较明显的影响。采用加性-显性遗传效应及贡献率分析模式,对改良回交二代群体的遗传参数的分析结果表明,株高、主茎数、单株结薯数、平均单薯重、匍匐茎长度、蛋白质含量、还原糖含量、Vc含量和芽眼深度等性状的遗传主要受基因加性效应控制,可通过早代选择来改良这些性状。而生育期和块茎比重的加性方差比率低于其显性方差比率,表明改良此类性状时应考虑利用其杂种优势的作用。所有测试性状对商品薯率的表现型方差贡献率CRP(C→T)不同。在所有测试的农艺性状中,除茎粗、单株产量对商品薯率的加性贡献率不显著外,其他11个性状对商品薯率的加性贡献率CRA(C→T)均达1%显著水平,并且单株结薯数、平均单薯重、比重、蛋白质含量、还原糖含量、Vc含量、生育期等性状对商品薯率的加性贡献率CRA(C→T)均高于其对表现型的贡献率。通过对平均单薯重、单株结薯数的间接选择可有效改良回交二代群体的商品薯率;所有测试性状对商品薯率的显性贡献率CRD(C→T)不同,选择生育期、茎粗显性效应高的组合,容易获得较高的商品薯率。根据对回交群体的遗传分析和不同改良方法的应用,提出了加速种间杂种群体的改良策略,以及提高马铃薯种间杂交育种效率的方法,可供参考。更多还原

【Abstract】 Narrow genetic background of cultivated potato (S. tuberosum) is crucial constraint for cultivar improvement, which has been testified by breeding practices all around the world. Fortunately, plenty of primal cultivated species and wild species of potatoes are still existed, which are potential germplasm for cultivar improvement and adopted gradually in potato breeding. As a valuable germplasm highly resistance to late blight, wild species, Solanum demissum, has been being used in potato breeding programs worldwide, by which good results were achieved. S. demissum (2n=72) originated from Mexico. About 200 cultivars related genetically with S. demissum were released worldwide. Except for resistance to late blight, S. demissum also possesses resistances to wart, scab, PVY, PVA, PLRV, and potato beetle, as well as high contents of protein and starch. It has been approved by breeding practices that S. demissum as a female parent can cross easily with cultivated species, and yield components such as more tubers and high specific gravity can be improved by 2~3 times of backcross by its hybrid progenies with cultivated varieties. However, cultivar improvement through crossing with wild species is time-consuming work. How to achieve favorable progresses in relative short time and speed up breeding procedure has been being hotspot attended by breeders.In this thesis, genetic parameters of progeny populations derived from 40 interspecies crosses were analyzed based on three crossing models. The purpose was to explore the effect of improvement of interspecies progeny population, find available methods for eliminating ill characters originated from wild species, and increase breeding efficiency through optimizing procedure of interspecies breeding. The final objective is to speed up breeding course of interspecies hybridization, and to increase efficiency of using wild species in cultivar improvement.The result showed that linkages and interactions of characters between cultivated species and wild species were lessened greatly by means of backcross hybrid population with cultivated varieties. Therefore, there is no any constraint for recombination of characters when S. demissum was used in conventional potato breeding programs.Correlations between some characters were inconsistent in various hybrid populations and backcross populations. The results indicated that correlation coefficients derived from one population cannot be used in others.By means of combining ability analysis, trial result from using the earliness of cultivated varieties to overcome long stolen and late tuberization of interspecific hybrid populations showed that significant variations at 0.01 level were found on mean single tuber weight, marketable tuber rate, length of stolen and variations at 0.05 level were found on yield per hill, tuber number per hill, maturity, specific gravity of tubers, protein content, vitamin content and reducing sugar content in cultivated varieties. Significant variations at 0.01 level were found on number of main stems, stem thickness, marketable tuber rate, and protein content, and significant variation at 0.05 level were found on yield per hill, tuber number per hill, mean tuber weight per hill, length of stolen, maturity, specific gravity and reducing sugar content in interspecific variety populations. Variation of parental interaction effects only was showed on tuber specific gravity significantly. General combining ability (GCA) value of the same character varied greatly among parents, and specific combining ability (SGA) value of the same character was also changeable among cross combinations. The result also showed that the earliness of cultivated varieties can overcome ill characters such as long stolen and late tuberization of wild species.Genetic parameters of first backcross populations derived from various crossing type were analyzed cytogenetically. The results showed that all effects brought by cytoplasm, nucleus, and interaction between cytoplasm and nucleus can be transferred into progenies obviously. Parental cytogenetic effects showed variation significantly in all characters tested. The nucleus effects of the combinations showed variations significantly in 9 characters tested except for plant height, number of main stems, reducing sugar and vitamin C content. Cytogenetic-nucleus interaction effects showed variation at 0.05 level on plant height, stem thickness, yield per hill, and protein content, showed variation at 0.01 level on tuber number per hill, reducing sugar and vitamin C contents. For the same character, effects aroused by cytoplasm and nucleus were varied dramatically among parental lines. Similarly, interaction effects of cytoplasm and nucleus for the same character were also varied greatly. Obvious genetic differences on progenies were found when a parental line used as male or female.Genetic parameters of the second backcross populations were analyzed based on the model of additive-dominant effect and contribution rate analysis. The results indicated that plant height, number of main stems, tuber number per hill, mean tuber weight, stolen length, protein content, reducing sugar content, vitamin C content and eye depth are mainly dominated by gene additive effects, which can be selected in early generations. The ratio of additive variances of maturity and specific gravity of tubers was less than dominant variances, which mean that heterosis would be available for those characters improvement. Contribution rate to phenotypic variances (CRP(C→T)) of marketable tuber rate of all characters tested were different. Except for stem thickness and yield per hill, additive contribution rate on marketable tuber rate (CRA(C→T)) of other 11 characters tested are all significant at 0.01 level, and CRA(C→T)of tuber number per hill, mean tuber weight, specific gravity, protein content, reducing sugar content, vitamin C content, and maturity were all higher than their CRP(C→T). Marketable tuber rate of the second backcross populations can be improved effectively by selecting mean tuber weight and tuber number per hill. Additive contribution rates to marketable tuber rate (CRD(C→T)) of all characters tested were also varied. Crosses selected based on maturity and stem thickness can easily improve marketable tuber rates.According to genetic analysis on backcross populations and application of various improving methods, strategy for accelerating the improving process of interspecific hybrid was made, by which breeding efficiency of interspecific hybridization can be increased.更多还原