蚂蚱麦和小白麦衍生系的遗传多样性分析

陕西关中蚂蚱麦和山西平遥小白麦是我国北方小麦品种的原始骨干亲本,解析蚂蚱麦和小白麦及其衍生系的遗传多样性对于小麦品种改良具有重要的参考意义。本研究利用小麦660KSNP芯片对蚂蚱麦、小白麦及其衍生品种(系)进行全基因组扫描,分析其遗传多样性。结果表明,小麦3个基因组的多态性SNP标记数为BAD,第4同源群的多态性标记数最少, 149份供试材料基因多样性(H)范围为0.095～0.500,平均值为0.336;核苷酸多样性指数(π)范围为0.272～0.435,平均值为0.340;而遗传相似系数(GS)变幅为0.335～0.997,平均值达0.619,表明蚂蚱麦和小白麦衍生系的遗传多样性较低。聚类分析表明蚂蚱麦和小白麦紧密地聚在亚群I,其衍生品种(系)分为5个亚群,其中2000年以前以蚂蚱麦或小白麦的单一衍生系为主,分在亚群I、II、III, 2000年以后多数品种同时拥有蚂蚱麦和小白麦血缘,分在亚群IV、V,遗传多样性较高,且与大面积推广品种聚为一类。因此,应加强优异基因资源导入,拓宽小麦品种的遗传基础,最终提高育种水平。     

小麦诱变后代的选择与运用研究

以杂交、物理引变、化学诱变三结合的突变育种方法,创造出各种类型的突变体材料 1860份.对突变体的类型及其利用途经分别进行了介绍.     

Use of radiations for breaking hybrid necrosis in wheat

Summary This report deals with a method of precluding hybrid necrosis lethality in wheat crosses by treatment of F₁ hybrid seeds with gamma rays from ⁶⁰Co source. Two crosses i.e. C306 × Kalyan 227 and C306 × U.S.A. 190 showing severe necrosis were treated with 15 kr and 20 kr doses and plants having mutated chimeras at tiller level and at leaf level were obtained, setting adequate seed for growing F₂ generation. The merits of the method have been discussed.     

Geographical distribution of genes causing hybrid necrosis in wheat

The distribution of Ne ₁- and Ne ₂-genes over varieties of the breeder's stock and over land varieties is discussed. It is preliminarily concluded that the area south and east of the line Mediterranean - Black Sea - Lake Baykal is an Ne ₁-area and the area north and west of this line is an Ne ₂-area.     

Chemically induced sterility in wheat for hybrid seed production

Summary The gametocidal effects of RH-531, RH-532, and RH-2956 were studied with three rates and times of foliar application on two spring wheat (Triticum aestivum L.) varieties, Anza and Yecora 70. RH-531 and RH-532 applied at or before booting stage caused rather large reduction in plant height while RH-2956 had a small effect on height. Application of any of the three chemicals on Anza at meiotic stages reduced self-pollination (SP) fertility by 97–99%. If 90% SP fertility reduction is acceptable, the application time could vary from premeiosis to postmeiosis for Anza. Yecora 70 was less sensitive than Anza to gametocide treatments. The lowest SP fertility obtained in Yecora 70 with RH-531, RH-532, and RH-2956 was by treatment at booting (4 kg/ha), at premeiosis (2 kg/ha), and heading (8 kg/ha), and the corresponding SP fertility reductions were 74, 89, and 71%. Pollen stainability-determined by aceto-carmine, IKI, and Alexander's stains-was not affected by gametocide treatment and was not useful in evaluating sterility induced by these chemicals. For the RH-531-treated Anza and Yecora 70 and the RH-532-treated Anza, more than 94% of the seeds produced by open-pollination on treated plants were from self-or sib-pollination as determined by progeny testing. However, RH-532-treated Yecora 70 and RH-2956-treated Anza and Yecora 70 did result in more crossed seeds, with a maximum of 20% outcrossing. It was believed that spike compactness induced by the chemicals and the related poor flower opening were the major limitations for outcrossing. Artificial pollinations made to the test varieties showed that RH-531 induced both male and female sterility and was undesirable for practical use. RH-532, however, could be applied at the booting stage to avoid severe female sterility, and RH-2956 clearly was the best of the three chemicals, with the female fertility very close to those of the untreated checks of both Anza and Yecora 70. Of the three chemicals, RH-2956 gave the highest percentage of hybrid plants in the progeny of hand-or open-pollinated spikes. Its practical use for hybrid seed production, however, will depend largely on improvement of methods to increase cross pollination in wheat.     

Yield and stability factors associated with hybrid wheat

For hybrid wheat to be accepted in the Great Plains of the USA, hybrids must exhibit enhanced yield performance, yield responsiveness, and reasonable yield stability across a wide array of production environments. Agripro has been researching hybrid wheat since 1981 and has an established pureline release history since 1978. Yield data from 1991 to 1995 were examined to compare the trend performance and selection gains of purelines and hybrids in a large scale parallel development effort. This data set (13,739 points) reveals an average 0.454 t ha^-1 or 10.8% hybrid yield advantage over purelines in preliminary regional testing. Entries selected from the preliminary trials show a greater hybrid advantage of 0.652 t ha^-1, or 13.5%. Several factors including enhanced stability over strong yearly environmental effects, improved agronomic and epidemiological expression through complementary inbred trait selection, and improved heat tolerance are likely contributors to this significantly improved selection gain. Yield stability of hybrids and purelines was compared in Agripro Standard Variety Trials and USDA-ARS Southern Regional Performance Nurseries from 1990 to 1995. In addition to having higher means than purelines, hybrid yield advantage increased with improving production conditions. The enhanced responsiveness of hybrids, as indicated by higher slopes in regression analyses, was combined with similar deviations from regression response. Hybrid wheat in the Great Plains of the USA has shown a fundamental yield, responsiveness and selection gain advantage over pureline varieties that could result in acceptance by producers. This revised version was published online in August 2006 with corrections to the Cover Date.     

利用小麦ⅹ玉米诱导小麦单倍体形成的研究

摘 要：利用小麦(Triticum aestivum L.)与玉米(Zea mays L.)进行远缘杂交,是获得小麦单倍体的一条重要途径,也是获得双单倍体(Double haploid ,DH)植株、构建小麦遗传群体的重要途径之一。本研究为创建小麦抗吸浆虫DH群体,在温室条件下对5个小麦抗、感吸浆虫杂交组合进行了单倍体诱导试验。结果表明：小麦不同基因型对诱导单倍体胚形成有较大影响;小麦授粉后2,4-D适宜的点药时间为6－36小时;适宜的2.4-D药液为 10－30mg/L;授粉后适宜的剥胚培养时间为14－16天,授粉后茎秆离体培养有较好的诱导效果,培养温度以20-250C为宜。本文提出了在温室条件下高效诱导小麦单倍体植株的方法及条件。     

Sources and distribution of the complementary genes for hybrid necrosis in wheat

Hybrid necrosis in wheat is based on 2 complementary genes Ne ₁ and Ne ₂. Unitl now among the 509 varieties and selections tested 89 Ne ₁-and 207 Ne ₂-carriers were found. By tracing the descendence of these carriers several sources of the necrosis genes (mostly land varieties) could be detected. At the same time it was demonstrated that notably the frequent use of certain carrier-varieties as parents in crosses has promoted the distribution of the necrosis genes.     

First supplementary list of genotypes of hybrid necrosis of wheat varieties

The genotypes of 107 varieties and selections are given. The author requests his colleagues to inform him about cases of hybrid necrosis they happen to come across during their work. This information will be published in a next supplementary list.Samenvatting Het genotype van 107 rassen en lijnen wordt gegeven. De schrijver verzoekt zijn collega's gevallen van bastaard-necrose, die zij bij hun werk tegenkomen, hem te willen mededelen.     

Second supplementary list of genotypes of hybrid necrosis of wheat varieties

Male sterile “lines” are being made carrying either Ne ₁ ^sor Ne ₂ ^sin homozygous condition. The “lines” will be used to determine the necrosis genotype of wheat varieties and at the same time to trace genes restoring fertility in cytoplasmic sterile “lines”. It is suggested that hybrid necrosis could be used in hybrid seed production. The article is concluded with a list of 100 varieties and selections of which the genotype for hybrid necrosis is given.     

Attempts to localize the gene Ch 1 for hybrid chlorosis in wheat

Summary Using Chinese Spring monosomics two procedures were applied to localize the gene Ch ₁ for hybrid chlorosis. This gene is present in certain provenances of Triticum macha var. subletshchumicum. Though the evidence is not conclusive, chromosome 2A is most likely the carrier of the Ch ₁ locus.     

普通小麦品种间以及与六倍体小黑麦种间杂种F1农艺性状的遗传分析

为给杂交选育优良小麦品种提供基础,本研究以普通小麦品种晋农190为父本,分别与9个普通小麦品种、7个六倍体小黑麦品种为母本配置杂交组合,对杂种F1代的农艺性状进行分析,发现除了无芒对有芒为显性之外,其余农艺性状均表现为数量遗传,F1代表现为超亲遗传或介于双亲之间。六倍体小黑麦的灰绿色叶片或茎秆、穗长长和红色不饱满的籽粒在杂种F1代显现,可作为鉴别真假杂种的典型性状。     

Geographical distribution of genes causing hybrid dwarfness in hexaploid wheat of the old world

Summary The distribution of the three different dominant genes for hybrid dwarfness in the Old World is given. It appears thatD ₁ is found in southern Europe, Africa and Asia, whileD ₃ is located in Europe.D ₂ is common in all wheat-growing areas. The distribution ofD ₁ coincides with that ofNe ₁, while the distribution ofD ₃ is probably similar to that ofNe ₂.TheD ₁-gene is still present inAegilops squarrosa. The sources ofD ₂ andD ₃ have not yet been determined with certainty.     

Screening for resistance to take-all in wheat,triticale and wheat-triticale hybrid lines

Summary Fifteen triticale and wheat-triticale hybrid lines were evaluated for resistance to the take-all fungus Gaeumannomyces graminis var. tritici and compared with five wheat and two rye lines in inoculated field and pot trials. The triticale and wheat-triticale hybrid lines varied in rye chromosome number and degree of resistance expressed. One line, Venus with seven pairs of rye chromosomes consistently showed levels of resistance intermediate between wheat and rye. A trend was observed where increasing rye chromosome content led to greater resistance but exceptions showed that variation within triticales could not be ascribed to rye chromosome content alone.     

杂交小麦抗坏血酸过氧化物酶基因克隆及其在种子老化中的潜在功能分析

以BS型二系杂交小麦BS1453/11GF5135及其BS1453(母本)、11GF5135(父本)的种子为材料,在BS1453/11GF5135中通过同源克隆获得抗坏血酸过氧化物酶基因TaAPX。该基因包含一个832 bp的ORF,共编码277个氨基酸。通过进一步生信分析预测miRNA与TaAPX基因的互作关系,发现TaAPX基因可能受miR396等抗逆及种子活力相关miRNAs的调控。另外通过蛋白互作预测分析,发现APX蛋白主要与氧化还原相关的酶互作反应。通过对不同老化时间的父母本及杂交种的胚进行qPCR及酶活性分析,发现TaAPX基因在杂交种及亲本中的表达趋势是先被诱导上调表达,后下调表达,但杂交种子内TaAPX基因的表达量在第7天才开始下降,而亲本种子内TaAPX基因的表达量在第5天开始下降,且miR396与TaAPX互为拮抗作用。随着老化时间的延长,亲本种子内APX酶活性表现为下降趋势,杂交种子内APX酶活性在第3天呈短暂下降趋势,随后上升,第9天开始下降,表明在老化条件下杂交种子内APX酶清除体内过氧化物的能力高于亲本,即杂交种抗老化能力高于其父母本,且TaAPX基因对种子...     

Towards a more efficient utilization of genic male sterility in breeding hybrid barley and wheat

The author suggests that in nature cytoplasms may occur which can restore fertility in male sterile lines in which male sterility is based on one recessive gene ms. If indeed such a fertilizing cytoplasm should be found a male sterile (S) ms ms-line could be increased using the male fertile counterpart (F) ms ms as a male. Thus the female rows in hybrid seed production fields consist of male sterile plants only. A method is outlined to trace a fertility restoring cytoplasm and to introduce it into a male sterile line.     

The possible use of mitochondrial complementation as an indicator of yield heterosis in breeding hybrid wheat

Summary Nine hybrid wheats and their six parental lines were grown in a field trial at two seed densities. The ADP:0 ratios for mitochondria extracted from the six parental lines and for the appropriate 1:1 mixtures of mitochondria from these parental lines were measured. The percentage additional mitochondrial efficiency of the mixtures over their more efficient parental line was found to be significantly correlated with the percentage yield heterosis of fully restored relatively disease-free hybrids grown at the lower seed density. These results indicate that measurements of mitochondrial complementation may have some value as a first screening of potential parental lines and may thus facilitate the rational choice of suitable material for producing hybrid wheat.     

Fourth supplementary list of wheat varieties classified according to their genotype for hybrid necrosis

Summary The previous conclusion about the geographical distribution of Ne-genes is supported by new evidence. Since now more data become available it is possible to divide regions within the Ne ₁- and Ne ₂-areas where certain alleles of these genes are common.The fourth supplement contains 685 varieties and selections of which the genotype for hybrid necrosis is given. The total number of tested varieties etc. is now 1835.     

Third supplementary list of wheat varieties classified according to their genotype for hybrid necrosis

Summary New data about the geographical distribution of necrosis genes support the previous conclusion, viz. the Old World can be divided by a rough line running through the Mediterranean and Black Sea countries to Lake Baikal and from these to northern Japan. The Ne ₁-area lies south and east and the Ne ₂ area north and west of this line. There are indications that Ne ₁-carrying wheat varieties exist in the Leningrad district.The third supplement contains 441 varieties and selections of which the genotype for hybrid necrosis is given. The total number of tested varieties etc. is now 1150.