一对等位基因互作控制的核雄性不育性

通过遗传工程能够产生由两个基因共同作用而形成的雄性不育。一个可以是能够导致雄性不育的基因,另一个可以是该雄性不育基因的活化基因,它们共同存在的时候表现雄性不育。利用位点特异性重组和转基因技术能够将这两个基因安排在植物同源染色体的相同位置上表达,成为等位基因,而获得分别只具有其中一个基因的两转基因系。它们之间杂交,F1中两个基因同时存在,F1产生雄性不育而成为不育系。常规品系与此F1不育系杂交,在杂种植株中,这两个基因不能同时存在,所有植株育性恢复。利用光温敏核不育性,化学杀雄和人工去雄可解决此不育系繁殖问题。该雄性不育性利用方式优越,育种简便易行,能够满足对最佳组合选育的要求,且能够定向培育目标杂交组合。     

104份甘肃小麦品种脂肪氧化酶和多酚氧化酶活性基因等位变异的检测

面粉和面制品的色泽是评价小麦品质的重要指标。小麦脂肪氧化酶(LOX)和多酚氧化酶(PPO)活性对面粉白度及面制品的色泽具有重要影响。为给甘肃省小麦品质育种提供参考依据,以104份甘肃省育成的小麦品种为材料,利用功能标记LOX16、LOX18、PPO18、PPO16和PPO29检测TaLox-B1、PpoA1及Ppo-D1位点的等位变异,分析甘肃小麦品种资源中LOX和PPO活性基因的组成和分布特点。结果表明,在甘肃小麦中,等位变异TaLox-B1a和TaLox-B1b的频率分别为22.12%和77.88%;其中,甘肃冬小麦品种高LOX活性等位变异TaLox-B1a的分布频率(30.56%)高于春小麦(3.13%)。等位变异Ppo-A1a、PpoA1b、Ppo-D1a和Ppo-D1b的频率分别为49.04%、50.96%、50.96%和49.04%;两个PPO基因的等位变异组合Ppo-A1a/Ppo-D1b、Ppo-A1a/Ppo-D1a、Ppo-A1b/Ppo-D1b和Ppo-A1b/Ppo-D1a的分布频率依次为28.85%、20.19%、20.19%和30.77%。说明在甘肃小麦品种中,低LOX活性等位变异(TaLox-B1b)品种比例较高;低PPO活性等位变异(Ppo-A1b、Ppo-D1a)品种分布比例略高于高PPO活性类型;其中,32份小麦品种在TaLox-B1、Ppo-A1和Ppo-D1三个位点同时含有高LOX活性和低PPO活性的等位变异。     

野生大豆育成品种与其亲本间的遗传多样性比较

[目的]鉴定大豆育成品种与其亲本间的遗传多样性差异和遗传多态性信息含量,为大豆育种提供参考。[方法]采用SSR标记技术对大豆育成品种与其亲本间的遗传多样性进行分析。[结果]野生大豆亲本总等位变异数和特有等位变异数分别是栽培大豆亲本的1.31倍和3.63倍;平均多态性信息含量由大到小依次为野生大豆亲本(0.545 0)、育成大豆品种(0.478 7)、栽培大豆亲本(0.415 6)。[结论]野生大豆的遗传背景复杂,遗传多样性丰富,其外部形态和内在遗传基础都与栽培大豆有明显差异。     

Detection of Allelic Variation in Chinese Wheat (Triticum aestivum L.) Germplasm with Drought Tolerance Using SSR Markers

Allelic variation in two domestic wheat landraces, Pingyaobaimai and Mazhamai, two cornerstone breeding materials and their derived cultivars with drought tolerance was detected by SSR (simple sequence repeat) markers. The clustering of 25 accessions showed that the similarity between Pingyaobaimai and Yanda1817, the latter was developed from the former, was 0.71, the highest one of all accessions, but the similarities were very low between these two accessions and other accessions including their derived cultivars. A similar situation was revealed between Mazhamai and its derived cultivars. Pingyaobaimai and its three derived cultivars shared three alleles at loci Xgwm526, Xgwm538 and Xgwm126 on chromosome arms 2BL, 4BL and 5AL, respectively. There were six shared alleles in Mazhamai and its derived cultivars, in order of Xgwm157,Xgwm126, Xgwm212, Xgwm626, Xgwm471 and Xgwm44 on chromosome arms 2DL, 5AL, 5DL, 6BL, 7AS and 7DC, respectively. Only one shared allele was detected between the pedigrees of Pingyaobaimai and Mazhamai. The difference of shared alleles in two cornerstone breeding materials and their derived cultivars revealed the diversity in Chinese wheat germplasm with drought tolerance and the complication in genetic basis of drought tolerance in wheat.     

麦谷蛋白亚基Clu-1和Glu-3位点基因等位变异对小麦品质特性的影响

甲单向一步SDS-PAGE方法分析表明亲本品种Suneca和Cook在麦谷蛋白亚基的5个位点(Glu-B1,Glu-D1,Glu-A3,Glu-B3和Glu-D3)均含不同等位基因。本研究重点对Suneca×Cook的F_4代群体中在麦谷蛋白亚基位点均为纯合基因的60个系的出粉率(FY),面粉蛋白质含量(FP)及和面时间(PTM)进行了分析,以研究麦谷蛋白各亚基位点等位基因变异及位点间互作对小麦品质特性的影响。结果表明,不同基因型间出粉率无显著差异,Glu-D1位点等位基因d和a对FP的效应存在显著差异,Glu-Dld基因(编码5 10亚基)的正效应显著高于Glu-Dla基因(编码2 12亚基);Glu-D1、Glu-A3和Glu-B3位点上基因的等位变异对PTM有显著和极显著影响,含Glu-Dld、Glu-A3b和Glu-B3b基因的系分别比含Glu-Dla,Glu-A3d和Glu-B3h基因的系有较长的和面时间;Glu-B1位点上等位变异i和u以及Glu-D3位点等位基因b和e分别对PTM无明显影响。在这种遗传背景下,麦谷蛋白亚基位点对PTM的效应大小依次排列为Glu-D1>Glu-B3>Glu-A3>GIu-B1=Glu-D3。Glu-1位点和Glu-3位点间对和面特性的影响存在累加效应和互作效应。     

光敏核不育水稻与BT型不育水稻存在等位基因关系的研究

实验以 BT 型不育水稻“寒丰 A”与“农量 58S”及其转育的5个光敏核不育水稻杂交,得到的 F_1植株均为不育,证明“农垦58S”不育的主效基因(ms(_1~p)ms(_1~p)ms(_2~p)ms(_2~p))中有一对来源于“农垦58”,即为与“寒丰 A”等位的不育基因。并推论“农垦58S”是由“农垦58”1个基因位点的突变,而它的光敏不育性则为此突变基因和原有不育基因相互作用的结果。     

Intra- and interpopulation diversity for HMW glutenin subunits in Spanish spelt wheat

The diversity of HMW glutenin subunits in spelt wheat, Triticum aestivum ssp. spelta, was studied electrophoretically in 333 accessions grouped in 50 populations originally collected from Asturias, North of Spain, in 1939. The inter- and intra-population distribution of HMW glutenin alleles at the Glu-A1, Glu-B1 and Glu-D1 loci were investigated. The results show that the genetic variation in HMW glutenin subunits is mainly present within populations, being the variation between populations only 21%. The materials analysed showed a wide polymorphism for the HMW glutenin subunits, although some allelic variants were clearly dominant. This suggests the possibility of a loss of variability before the collection that could have increased with the subsequent reduction of the cultivation area of this species in this Spanish region.     

花生ahFAD2A等位基因表达变异与种子油酸积累关系

花生ahFAD2A是控制种子油酸、亚油酸含量和油亚比的关键基因。利用ahFAD2A基因特异引物检测远杂9102, 豫花9416等52个花生品种的ahFAD2A基因等位变异, 并比较其中13个品种的ahFAD2A基因序列。结果表明, 花生ahFAD2A基因存在G-A两种单核苷酸等位变异(野生型ahFAD2A-wt和突变体ahFAD2A-m), DNA序列比对结果证实, 豫花9416等10个品种(突变体)与远杂9102、延津花籽和开农白2号(野生型)相比, 在ahFAD2A基因的448 bp处存在核苷酸G-A突变。应用real-time PCR检测ahFAD2A等位基因在种子不同发育时期的表达动态显示突变体豫花9416等位基因(ahFAD2A-m)在种子发育中期表达量稍高, 种子发育后期表达量下降速度较野生型远杂9102(ahFAD2A-wt)更快。进一步测定豫花9416和远杂9102在种子不同发育时期的油酸、亚油酸积累和油亚比动态, 发现两品种间存在明显差异, 豫花9416在籽粒发育前期油酸相对含量已超过亚油酸, 油亚比大于１并逐渐增加, 而远杂9102到籽粒发育中后期油酸相对含量才高于亚油酸, 油亚比逐渐接近于１左右。     

油菜素内酯代谢相关基因BAS1等位变异影响小麦籽粒密度及粒重表型

BAS1(phy B activation-tagged suppressor1)是调控油菜素内酯活性的关键基因。本研究利用由和尚麦和豫麦8679杂交后代构建的RIL群体(包括129个家系),研究了BAS1和小麦千粒重、籽粒密度两个产量性状的关系。结果表明BAS1基因位点等位变异对千粒重和籽粒密度具有显著的影响,B型等位基因的家系其千粒重和籽粒密度均值均显著高于A型等位基因的家系。相关分析表明,BAS1位点等位变异分别与千粒重和籽粒密度呈显著(0.178*)和极显著(0.327***)正相关。研究结果揭示了BAS1基因位点等位变异与小麦粒重、籽粒密度间的密切联系,这对解释小麦产量形成机制及其指导高产育种具有重要的意义。     

Genetic Diversity and Allelic Frequency of Selected Thai and Exotic Rice Germplasm Using SSR Markers

A collection of 167 Thai and exotic rice accessions was subjected for evaluation of genetic diversity and assessment of relationship by simple sequence repeat(SSR) markers. Among a total of 49 SSR markers, 13 markers distributing over 12 rice chromosomes showed clear polymorphic band patterns, and they were selected for genetic assessment. A total of 110 alleles were detected with an average of 8.46 alleles per locus. The averages of gene diversity, heterozygosity and polymorphic information content were 0.59, 0.02 and 0.56, respectively. The unweighted-pair group method with arithmetic averages(UPGMA) clustering analysis was performed for genetic distance, and phylogenetic tree was constructed. The result showed that this rice collection was divided into two major groups, classified as japonica and indica subspecies. Within the japonica group, temperate japonica and tropical japonica subgroups can be clearly separated. Three-dimensional principal component analysis projection and model-based population structure analysis showed consistent clustering results with two major groups of UPGMA analysis, supporting the classification of japonica and indica subspecies. The indica allelic frequency was also investigated to provide an indicative guide for breeders to overcome the practical problems on sterility of inter-subspecies hybrid offspring. This rice collection and information obtained in this study will be useful for rice breeding programs.