小麦黄矮病新抗源中4,中5的选育及应用研究

中4、中5是用经过连续3年系统选育的天蓝偃麦草作父本,地理远缘的小麦品种克强与南大2419杂交的F_5后代材料作母本,通过两者杂交,并采取延长生育法等技术克服F_1不育性,经过连续9年选育而成.对小麦黄矮病高抗,对条、叶、秆三种锈病的多种生理小种均表现免疫至高抗,还具有高蛋白(含量17.08%、17.13%);高赖氨酸(含量为0.483%、0.50%)等特点,是人工合成的优异的小麦多抗、优质资源.用中4、中5与普通小麦杂交,已成功地将抗黄矮病基因转移到普通小麦,育成陕麦8007、陕麦8124、忻4070、忻4079、中1001等品种(系).     

小麦主茎总叶数的变异

小麦主茎总叶数是重要的植株性状。它也具有变异性。春型品种的主茎叶数少,冬型品种的主茎叶数多,过渡型品种居中。在不同播期中,强春性小麦的主茎叶数相近,一般春性品种变化不大。随着播期的推迟,过渡型和冬型品种的主茎总叶数逐渐发生变化,冬型品种的变化幅度大。冬播期中,在翌春出苗的情况下,所有品种的主茎总叶数都较少,     

K—19型小麦雄性不育系的创建及其育性恢复源的发现

以粘果山羊草Ａｅ．１９（Ａｅ．ｋｏｔｓｃｈｙｉ，１９）为母本，中国春和云南铁壳小麦为桥梁亲本，进行远缘杂交，获得雄性不育株。再用普通麦７８－１等为轮回亲本，与其测交并连续回交，育成了Ｋ－１９－７８－１Ａ等小麦雄性不育系。然后用５００余份普通小麦品种（系）与Ｋ－１９－７８－１Ａ进行测交，获得４６９个组合Ｆ１杂种，其中７３个测交种（占总数的１５．５７％）能完全保持Ｋ－１９型小麦的雄性不育性。其余３９６个测交种（占总数的８４．４３％）对Ｋ－１９型小麦雄性不育系表现不同程度的育性恢复。恢复度幅度为１．０％～９７．５％。３９６份材料中有１４．１４％对Ｋ－１９型不育系表现高度恢复，按国内法计算恢复度达到８０．１％～９７．５％；测交、回交后代产生单倍体频率在０～１７．５％之间，发现一批综合性状好、不产生单倍体的保持系和恢复源。     

不同小麦品种籽粒灌浆特性的研究

以黄淮南片主产麦区广泛种植和新近育成推广的12个小麦品种为供试材料,对籽粒灌浆特性进行研究.结果表明:籽粒平均灌浆速度及最大灌浆速度均与百粒重、籽粒体积和籽粒最大体积呈极显著的正相关;籽粒灌浆持续期仅与饱满指数呈显著的正相关,而与百粒重无显著相关.供试品种的籽粒平均灌浆速度和最大灌浆速度,均以郑州853、陕农7859为最快,灌浆持续期最短,属晚花基因型品种;冀麦5418和徐州21的灌浆持续期最长,属早花基因型品种.还探讨了黄淮麦区南片小麦籽粒灌浆模式.     

冬小麦各生育期~(14)C-光合产物的分配与再分配

利用示踪同位素碳~(14)研究了冬生长阶段光合产物的分配以及冬后各阶段的连续分配情况.结果表明,光合产物生成后,分配并不停止.在冬后各阶段观察到存在着连续再分配.连续分配中心从地下根系、分蘖节、主茎叶,逐渐向上,直至穗部.然而,除了该中心外,其它器官或组织也能获得一定数量的光合产物.     

大豆重组自交系群体荚粒性状的QTL分析

利用大豆重组自交系soy01群体中的255个家系进行2年田间试验，采用两种作图方法，寻找一粒荚、四粒荚、每荚粒数等5个荚粒性状稳定的QTL。结果表明，利用区间作图法，2年共找到24个荚粒性状QTL，解释的遗传变异为5%~80%；利用复合区间作图法，2年共找到27个荚粒性状QTL，解释的遗传变异为4%~73%。利用复合区间作图法，2年找到2个重复出现、稳定的四粒荚QTL和2个每荚粒数QTL，为大豆荚粒性状QTL的精细定位和分子标记辅助育种提供了基础和依据。     

Characterization of dinucleotide and trinucleotide EST-derived microsatellites in the wheat genome

Over the past decade microsatellites or simple sequence repeats (SSRs) have attracted a considerable amount of attention from researchers. The aim of the present paper was to analyse expressed sequence tag-derived SSR (EST-SSR) marker variability in wheat and to investigate the relationships between the number and type of repeat units and the level of microsatellite polymorphism. Two hundred and forty-one new EST-SSR markers available in a public database () were characterized in eight durum wheat cultivars (Svevo, Ciccio, Primadur, Duilio, Meridiano, Claudio, Latino, Messapia), two accessions of Triticum turgidum var. dicoccoides (MG4343, MG29896), one accession of T. turgidum var. dicoccum (MG5323) and in the common wheat cv. Chinese Spring. Of these, 201 primer pairs (83.4%) amplified PCR products successfully, while the remaining 40 (16.6%) failed to amplify any product. Of the EST-SSRs analysed, 45.2% of the primer pairs amplified one or two PCR products. Multiple discrete PCR products were observed among both di- and trinucleotide EST-SSR markers (31.2 and 40.5%, respectively). Markers based on dinucleotide microsatellites were more polymorphic than those based on trinucleotide SSRs in the 12 wheat genotypes tested (68.9 and 52.7%, respectively). An average of 2.5 alleles for dinucleotide and 2.0 alleles for trinucleotide SSRs was observed. The data reported in the present work indicate the presence of a significant relationship between motif sequence types and polymorphism. The primer set based on the AG repeat motif showed the lowest percentage of polymorphism (55.0%), while the primer set based on the AC repeat motif showed t he highest percentage (85.0%). Among trinucleotide SSRs, the AGG microsatellite markers showed the highest percentage of polymorphism (70.0%), and the ACG motif the lowest value (25.0%). The characterization of these new EST-SSR markers and the results of our studyon the effect of repeat number and type of motifs could have important applications in the genetic analysis of agronomically important traits, quantitative trait locus discovery and marker-assisted selection.     

利用SDS-PAGE鉴定转基因小麦HMW-GS的表达类型和后代遗传

采用SDS-聚丙烯酰胺凝胶电泳(SDS-PAGE)在蛋白质水平上对T2～T5代小麦转基因株系高分子量谷蛋白亚基(HMW—GS)的遗传表达及其分离进行了鉴定和分析。结果发现，外源1Dx5和1Dy10基因在T2代部分株系中表达；在有的株系中出现了原亚基(8亚基)的缺失或沉默和新亚基(暂定8^*)的产生，因而检测出2 5 10 12，2 5 7 8^* 10 12，5 7 10，2 7 10 12的多种类型。对2 5 10 12型株系进行了多代跟踪分析，发现其在T2～T5代陆续发生分离，存在于不同单株、不同单穗的子粒和同一单粒后代之间。经筛选，获得了天然不存在的亚基类型为2 5 10 12，2 10 12，2 5 12等稳定表达的种质创新株系。     

Intergeneric hybrid between Brassica napus and Diplotaxis harra through ovary culture and the cytogenetic analysis of their progenies

Brassica napus (2n = 38) and Diplotaxis harra (2n = 26) were used to investigate gene transfer from D. harra to B. napus. Intergeneric F₁ hybrids (dihaploid 2n = 32 chromosomes) were obtained through ovary culture. The chromosome associations in the first meiotic division was (0–2)_III + (2–10)_II + (12–28)_I. Many seeds were harvested in the F₁ hybrid after backcrossing with B. napus, and from open pollination of the F₁ hybrid. Somatic chromosome numbers of BC₁ and hybrid plants varied from 2n = 26 to 52. In the first meiotic division, high frequencies of bivalent association and relatively low pollen fertility were observed. BC₂ plants generated from the BC₁ plants with 2n = 38 chromosomes, 69.6% showed 2n = 38 chromosomes. Many aneuploids with addition and deletion of chromosomes were also obtained. A bridge plant between B. napus and D. harra with 2n = 32 chromosomes should be valuable material for the breeding of brassica crops.     

小麦品种对赤霉病的抗性鉴定

用孢子悬液小花注射接种法测定了47个小麦品种对赤霉病的抗性，分析了小穗侵染率与小麦农艺性状间的相关性。结果表明，47个小麦品种中，没有高抗品种，抗病品种8个，占17．02％，中抗品种27个，占57．44％，感病品种10个，占21．28％，高感品种2个，占4．26％。小穗侵染率与株高、穗长、千粒重、千粒重损失率，穗密度等农艺性状相关皆不显著，与生育期相关极显著。