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1.
Polymorphism of waxy proteins in Iberian hexaploid wheats 总被引：4，自引：0，他引：4
A collection of 130 cultivars of bread wheat, 332 landraces of bread wheat and 144 spelt wheats was analysed for waxy proteins in the grain. The electrophoretic patterns showed very low polymorphism and most of the hexaploid wheats had the Wx-Ala, Wx-D1a and Wx-B1 alleles of ‘Chinese Spring’. Two alleles were detected at Wx-A1 (Wx-A1a, and Wx-A1b (null)), the latter was present in only 5.1% of the bread wheat landraces and 7.6% ofthe spelt wheats. No allelic variation was found at the Wx-D1 locus and all the hexaploid wheats had the Wx-D1a allele. Wx-B1 was the most polymorphic locus, with three alleles detected: Wx-B1a, Wx-B1b (null) and Wx-Blc coding for a Wx-B1 protein with a slightly different mobility from Wx-B1a. The null Wx-B1b allele was found in 10.8% of the bread wheat cultivars, 21.4% of the bread wheat landraces and 12.5% of the spelt wheats. Among the 604 hexaploid wheats analysed, only two bread wheat landraces (0.6%) and two spelt wheats (1.4%) had the null allele at both Wx-A1 and Wx-B1 loci. 相似文献
2.
Genetic diversity of high-molecular-weight glutenin subunit compositions in landraces of hexaploid wheat from Japan 总被引：7，自引：0，他引：7
Hiro Nakamura 《Euphytica》2001,120(2):227-234
The high-molecular-weight (HMW) glutenin subunit composition of seed storage protein of 174 Japanese hexaploid wheat (Triticum aestivum) landraces have been examined by using sodium dodecyl sulfate polyacrylamide gel electrophoresis system. Twenty four different,
major glutenin HMW subunits were identified, and each of the landraces contained three to five subunits and 17 different glutenin
subunit patterns were observed for 13 alleles in the landraces. On the basis of HMW glutenin subunits composition, Japanese
landraces showed a specific allelic variation, close to Japanese commercial wheats in HMW glutenin subunits, different from
those in alien hexaploid wheats. Further, it could be concluded that all common glutenin alleles can be found in the 174 landraces
originated from Japan. The variation detected in the glutenin subunits is useful for variety identification, has a bearing
on our understanding of hexaploid wheat genetic resource evolution in Japan, and raises questions concerning the nature of
this genetic variation.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
3.
Photoperiod response is of great importance for optimal adaptation of bread wheat cultivars to specific environments, and
variation is commonly associated with allelic differences at the Ppd-D1 locus on chromosome 2D. A total of 926 Chinese wheat landraces and improved cultivars collected from nine wheat growing zones
were tested for their genotypes at the Ppd-D1 locus using allele-specific markers. The average frequency of the photoperiod-insensitive Ppd-D1a allele was 66.0%, with the frequencies of 38.6 and 90.6% in landraces and improved cultivars, respectively. However, the
Ppd-D1a allele was present in all improved cultivars released after 1970 except for spring wheats in high latitude northwestern China,
and winter wheats in Gansu and Xinjiang. The presence of the Ppd-D1a allele in landraces and improved cultivars increased gradually from north to south, illustrating the relationship between
photoperiod response and environment. Ppd-D1a in Chinese wheats is derived from three sources, Japanese landrace Akagomughi and Chinese landraces Mazhamai and Youzimai.
The current information is important for understanding the broad adaptation of improved Chinese wheat cultivars.
F. P. Yang and X. K. Zhang contributed equally to this work. 相似文献
4.
5.
Gliadin alleles were identified in 100 common wheat cultivars registered and/or grown in Spain during the last 40 years. A very high level of genetic polymorphism was found: in total, 103 allelic variants including one null‐allele were found at the six major Gli loci in the Spanish wheats studied. An average genetic diversity for these six loci was found to be higher (H=0.844) than in any group of wheat cultivars studied previously. Spanish wheats bred in Spain demonstrated even higher genetic diversity (H=0.868), probably because of the occurrence in this group of some landraces (local varieties) assumed to be strongly differentiated to fit local environments. The high level of genetic diversity of wheats grown in Spain was maintained by the introduction of distantly related wheat germplasm from different sources, especially from Italy and CIMMYT. A slight decrease of genetic diversity in recently registered cultivars might be caused by the excessive introduction of French wheats. Thirteen new alleles found in Spanish wheats were catalogued, including Gli‐D2w which encodes the first Gli‐D2‐controlledγ‐gliadin to be found. 相似文献
6.
The purpose of this study was to identify the species of local landraces of wheat (Triticum spp.), held in the Israel Gene
Bank, to evaluate them for basic characters and to assess their response to infection by two rust fungi under artificial inoculation
conditions. One-hundred-thirty one seed samples were collected from local or Beduin farmers during 1978–1981 throughout the
Galilee, Mt. Gilboa. Judean Desert and the south Negev. The samples were collected and stored in the Israel Gene Bank without
any characterization or evaluation. Each accession was planted in a 1 m row at Bet Dagan and grown under favorable conditions
for plant growth and rust development. Determination of the species, data of plant height, days to heading and reaction of
the landraces to artificial inoculation with a composite inoculum of Puccinia recondita and P. striiformis were collected
from each row. A small part of the landraces collection consisted of mixed populations of T. durum and T. aestivum plants,
where one of the two species was predominant. One-hundred-fourteen and 17 accessions from this collection represented, respectively,
Triticum durum and T. aestivum Israel landraces. Large variations were found for all the characters examined. Of the total
accessions, 6.5% (8 accessions) and 32% (42 accessions) were resistant, respectively, to yellow- and leaf-rust. It was concluded
that the diversified populations of the local landraces of wheat can be used as a source not only for genes affecting basic
characters such as plant height and heading date, but also for resistance to leaf rust and yellow rust.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
7.
Bringing wild relatives back into the family: recovering genetic diversity in CIMMYT improved wheat germplasm 总被引：6，自引：0，他引：6
M. L. Warburton J. Crossa J. Franco M. Kazi R. Trethowan S. Rajaram W. Pfeiffer P. Zhang S. Dreisigacker M. van Ginkel 《Euphytica》2006,149(3):289-301
Summary The dangers of a narrow genetic base of the world's major domesticated food crops have become a great global concern in recent decades. The efforts of the International Maize and Wheat Improvement Center (CIMMYT) to breed common wheat cultivars for resource poor farmers in the developing world (known as the Green Revolution wheats) has met with notable success in terms of improved yield, yield stability, increased disease resistance and utilization efficiency of agricultural inputs. However, much of the success was bought at the cost of an overall reduction in genetic diversity in the species; average Modified Roger's distances (MRD) within groups of germplasm fell from 0.64 in the landraces to a low of 0.58 in the improved lines in the 1980s. Recent efforts by CIMMYT breeders to expand the genetic base of common wheat has included the use of landraces, materials from other breeding programs, and synthetic wheats derived from wild species in the pedigrees of new advanced materials. The result, measured using SSR molecular markers, is a highly significant increase in the latent genetic diversity of recently developed CIMMYT breeding lines and cultivars compared to the original Green Revolution wheats (average MRD of the latest materials (0.63) is not significantly different from that of the landraces, as tested using confidence intervals). At the same time, yield and resistance to biotic and abiotic stresses, and end-use quality continue to increase, indicating that the Green Revolution continues to this day. 相似文献
8.
Wheat germ agglutin (WGA) present in the embryo of a bread wheat grain is a mixture of three isolectins, viz CLA, CLB and CLD which are coded by genes located on die chromosomes 1A, 1B and 1D. Their respective absolute amounts were determined in 62 Nigerian and five Chad landraces. Added was the Madagascar variety ‘Kanem’ which is stated to be selected from Chad material. Some of the Nigerian landraces were formerly identified as derived from Indian Pakistani wheat varieties/landraces introduced into Northern Nigeria before 1940. These had relatively high CLD/GLA and CLB/CLA ratios. Other Nigerian landraces with such high ratios were postulated to come from India/Pakistan, too. The Chad wheats, except ‘Kanem’, have WGA amounts and-ratios similar to those native to Northern Nigeria. This may point to a common history. ‘Kanem’ is said to be bred in Madagascar from Chad wheats. Apparently it has a different origin. So the determination of the WGA amount and its isolectin composition is a helpful means to identify the history of a land race or of an improved variety. 相似文献
9.
C. H. A. Snijders 《Euphytica》1990,50(2):171-179
Summary During a four year period, a total of 258 winter and spring wheat genotypes were evaluated for resistance to head blight after inoculation with Fusarium culmorum strain IPO 39-01. It was concluded that genetic variation for resistance is very large. Spring wheat genotypes which had been reported to be resistant to head blight caused by Fusarium graminearum were also resistant to F. culmorum. The resistant germplasm was divided into three gene pools: winter wheats from Eastern Europe, spring wheats from China/Japan and spring wheats from Brazil. In 32 winter wheat genotypes in 1987, and 54 winter wheat genotypes in 1989, the percentage yield reduction depended on the square root of percentage head blight with an average regression coefficient of 6.6. Heritability estimates indicated that for selection for Fusarium head blight resistance, visually assessed head blight was a better selection criterion than yield reduction. 相似文献
10.
为了筛选综合性状较好的可用于小麦品质改良的农家种资源,以212份小麦农家种为材料,采用Vp1B3分子标记和田间喷雾进行了抗穗发芽鉴定,用硬度指数法进行了硬度测定,并考察了部分农艺性状。结果表明,212个农家种中Vp-1Ba（感穗发芽）、Vp-1Bb（抗穗发芽）和Vp-1Bc（抗穗发芽）基因型的频率分别为70.28%,6.16%,23.70%,以Vp-1Ba基因型为主。3种基因型穗发芽率差异不显著,212个农家种的穗发芽率在7.79%~28.56%之间,平均为15.28%;农家种硬度指数(HI)平均值为71.22;农家种平均株高达到113.46 cm;农家种对白粉病抗性变异丰富,有3个品种为白粉病免疫;农家种平均穗粒数为28.33,平均千粒重为30.96 g。针对抗穗发芽、籽粒硬质、株高适宜、抗白粉病、高产等育种目标,筛选出等‘金包银’、‘玉麦1’、‘大红芒2’等12个种质材料,为进一步培育优质小麦奠定了基础。 相似文献
11.
硫代硫酸硫转移酶参与植物体内的硫代谢、氰化物的清除以及活性氧的生成与清除,与植物抗病反应密切相关。小麦抗、感白粉病近等基因系材料在接种白粉菌后均诱导表达硫代硫酸硫转移酶基因TaTST,并在接种后0~48 h内呈现2次诱导峰值,分别与白粉菌初次接触识别和附着胞侵入、吸器形成时间相对应,也与2次氧突发时间对应。TaTST在感病材料上的诱导表达水平明显高于在抗病材料上,由此导致的活性氧过度清除可能是导致感病反应的原因之一。TaTST也参与抗病反应过程。利用病毒诱导的基因沉默技术(virus-induced gene silencing, VIGS)创造了TaTST基因沉默的抗病植株。尽管充分发病时间后沉默植株叶片上并未观察到肉眼可见的病斑,但侵染早期白粉菌成功侵入频率的增加和次级菌丝的有限伸长说明TaTST沉默植株抗病水平下降。TaTST沉默导致乳突致密度下降和H2O2在细胞内的扩散时间延迟。因此,TaTST可能通过调节活性氧的积累和扩散、乳突的形成等小麦-白粉菌互作早期的寄主细胞反应而参与小麦对白粉菌的抗侵入过程。 相似文献
12.
山东小麦籽粒硬度演变规律研究 总被引：4，自引：0，他引：4
利用单籽粒谷物特性测试仪和PCR扩增、酶切及DNA测序技术,结合改良的friabilin提取及电泳分析方法,对山东省431份农家品种、63份历史品种和29份当前主栽品种的籽粒硬度分布以及Pina和Pinb等位变异类型进行研究,以探讨山东小麦籽粒硬度的演变规律。农家品种、历史品种和当前主栽品种中硬质麦比例分别为75.6%、12.7%和27.6%,混合麦分别占20.4%、19.0%和13.8%,而软质麦分别占3.9%、68.3%和58.6%。农家品种中共有6种基因型,Pina-D1b/Pinb-D1a和Pina-D1a/Pinb-D1p分别占硬质麦的38%和59.6%。历史品种中有4种基因型,8份硬质麦中Pina-D1b/Pinb-D1a占37.5%,Pina-D1a/Pinb-D1b占37.5%,而Pina-D1a/Pinb-D1p只占25.0%。当前主栽品种中,8份硬质麦全部是Pina-D1a/Pinb-D1b类型。长芒透垅白等3个品种的Pinb基因的核苷酸序列发生了双突变,起始密码子下游96 bp处碱基C突变为A,而且在265 bp处发生了A碱基的缺失,将其命名为Pinb-D1aa。 相似文献
13.
Rishi R. Burlakoti Mohamed Mergoum Shahryar F. Kianian Tika B. Adhikari 《Euphytica》2010,172(2):197-205
Fusarium head blight (FHB) is a devastating disease in wheat throughout the world. FHB resistance consists of two components: resistance
to initial infection (type I) and resistance to spread within infected spikes (type II). Current wheat breeding programs for
FHB focus on type II resistance, which limits pathogen spread but may not be sufficiently durable. To combine type I with
existing type II resistance, 113 F9-derived recombinant inbred lines (RILs) were developed from a cross between three wheat genotypes Frontana, W9207, and Alsen.
The RILs were evaluated for resistance to initial infection, FHB spread within spike, kernel damage, and deoxynivalenol (DON)
content in two independent greenhouse experiments in 2006 and 2007. Among the 113 RILs, 20% lines showed ≤10% initial disease
severity (IDS) and ≤11 to 30% final disease severity (FDS), and 19% had DON content ≤5 μg/g. Approximately 11% of the RILs
showed tendency of higher resistance (as exhibited by lower IDS, FDS, and DON content) than the resistant parents. The 42
of the FHB-resistant RILs were analyzed with seven simple sequence repeat (SSR) markers or microsatellites known to be linked
to FHB resistance. Approximately half of the RILs had molecular markers linked to both types of FHB resistance indicated
the presence of type I and II resistance alleles in the RILs. The resistant RILs identified in this study should be useful
for the future improvement of FHB resistance in spring wheat. 相似文献
14.
R. I. H. McKenzie R. J. Lamb T. Aung I. L. Wise P. Barker O. O. Olfert R. I. McIntosh 《Plant Breeding》2002,121(5):383-388
Inheritance of resistance to a wheat midge, Sitodiplosis mosellana (Géhin), was investigated in spring wheats derived from nine resistant winter wheat cultivars. F1 hybrids were obtained from crosses between resistant winter wheats and susceptible spring wheats, and used to generate doubled haploid populations. These populations segregated in a ratio of 1:1 resistant to susceptible, indicating that a single gene confers the resistance. The F2 progeny from an intercross among spring wheats derived from the nine resistance sources did not segregate for resistance. Therefore, the same gene confers resistance in all nine sources of resistance, although other genes probably affect expression because the level of resistance varied among lines. Heterozygous plants from five crosses between diverse susceptible and resistant spring wheat parents all showed intermediate levels of response, indicating that resistance is partly dominant. Susceptible plants were reliably discriminated from heterozygous or homozygous resistant ones in laboratory tests, based on the survival and development of wheat midge larvae on one or two spikes. This powerful resistance gene, designated Sm1, is simply inherited and can be incorporated readily into breeding programmes for spring or winter wheat. However, the use of this gene by itself may lead to the evolution of a virulent population, once a resistant cultivar is widely grown. 相似文献
15.
The diversity of head-scab resistance in Triticeae and their relation to ecological conditions 总被引：3，自引：0，他引：3
1507 accessions from 93 species of 18 genera in Triticeae were screened for resistance to initial infection and resistance
to pathogen spread with multi-floret and single-floret injection inoculation methods respectively. The accessions with high
resistance were mainly found in perennial genera: Roegneria, Hystrix, Agropyron, Kengyilia and Elymus. Based on differences
in resistance, 18 genera screened in Triticeae could be classified into five groups. The species with high resistance were
mainly distributed in humid ecological environments.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
16.
A total of 140 diverse spring wheat lines were characterized for agronomic and physiological traits under hot field conditions, and a subset of thirteen were selected for dark leaf respiration studies (Rd). These genetic resources included synthetic-derived lines, landraces, landrace-derived lines, bread wheats, and durum wheats. Initial phenotyping showed that better heat-adapted genotypes (best yielding) exhibited high early biomass (assessed by normalized difference of vegetative index, NDVI), high grainfilling rates, and low canopy temperatures. As for other studies Rd increased as temperature increased (within the range of 15–40 °C), and decreased with plant age. Correlations between Rd and leaf temperature ranged between 0.50 and 0.85. Rd was negatively associated with yield when recorded at 30–35 °C during anthesis and grainfilling. Comparisons between wheat groups showed that synthetic-derived materials expressed lower leaf respiration rates and larger yields than the other groups at warm temperatures. 相似文献
17.
Three commercial Indian wheat varieties —‘Sonalika’, ‘Kalyansona’ and ‘Janak’ were used to develop homogeneous and heterogeneous lines for leaf rust resistance, utilizing diverse sources of resistance from fourteen donors. Four kinds of multilines were developed to study coefficients o: infection, areas under disease progress curves (AUDPC), rates of spread and grain yields over their component means. Heterogeneous populations showed minimum coefficients of infection at initial as well as final stages, which were less than or equal to the resistant component even in dirty multilines carrying up to 50 % susceptible populations. Large reductions in coefficients of infection and in AUDPC were also observed. Rate of spread was independent of coefficient of infection and AUDPC. Grain yield advantage over both component means and recurrent parents was higher in clean multilines. The significance of the use of multilines in limiting losses due to disease is discussed. 相似文献
18.
小麦纹枯病抗源的遗传多样性及抗性基因位点SSR标记分析 总被引：1，自引：0，他引：1
为揭示小麦纹枯病抗源的遗传多样性,发掘优异的抗性种质,利用沟带接种法对前期筛选出的88份抗性种质进行了3年田间抗性鉴定,鉴定出抗或中抗纹枯病的小麦种质32份。利用分布于全基因组的SSR标记对这些抗源进行了遗传多样性分析,59个SSR标记共检测到308个等位变异,每个标记可以检测到2~13个等位基因,平均5.2个;多态性信息含量(PIC)的变异范围为0.12~0.89,平均为0.61,表明材料的遗传丰富度较高。根据聚类分析和主成分(PCA)分析,32份小麦纹枯病抗源按照遗传相似系数可划分为2个组群,国外引进品种和国内改良品种聚为一类,国内农家品种聚为一类,并且与地理分布特征相符。利用与纹枯病抗性QTL紧密连锁的14个SSR标记对32份抗源进行基因型分析,发现与抗性QTL连锁的2BS上的Xwmc154和7DS上的Xbarc126普遍存在,可用于分子标记辅助选择。在武农148、陕983、陕农78、Coker 983、H-Line、Mason和Compair中仅检测到一个已报道的抗病QTL,而在Tyalt中没有检测到已知抗病QTL,这些材料有可能携带新的纹枯病抗性基因/QTL,可以在育种中加以利用。 相似文献
19.
Chunjun Li Huilan Zhu Caiqin Zhang Feng Lin Shulin Xue Yong Cao Zhengzhi Zhang Lixia Zhang Zhengqiang Ma 《Euphytica》2008,163(2):185-191
Fusarium head blight (FHB), or scab, is a devastating wheat disease worldwide, reducing both grain yield and quality. The
percentage of Fusarium-damaged kernels (FDK) directly reflects the damage level caused by scab on wheat grains and its variation
represents the so-called type IV scab resistance in germplasm. To identify genes governing type IV resistance and investigate
its relationship with other scab resistance types, we mapped QTLs associated with percent FDK using data from three different
field evaluations of the recombination inbred line (RIL) population derived from the susceptible cultivar Nanda 2419 × the
scab-resistant cultivar Wangshuibai. Five QTLs related to percent FDK were identified in at least two different trials, for
which Wangshuibai contributed four of the resistance alleles. Most of the FDK-related QTLs, including the three with larger
effects, QFdk.nau-2B, QFdk.nau-3B and QFdk.nau-4B, mapped to intervals associated with either type IV resistance or type II resistance. Moreover, most of the major type I
and type II resistance QTLs detected previously were associated with type IV resistance, suggesting that resistance to initial
infection and disease spread play major roles in conditioning less FDK. Therefore, breeders have options to choose inoculation
methods based on their expertise and resources without risking significant loss of information when using percent FDK as the
disease index. The most useful scab resistance QTLs for breeding would be those with stable influences on FDK and/or deoxynivalenol
(DON) accumulation besides the initial infection and disease spread.
Chunjun Li and Huilan Zhu contributed equally to this work. 相似文献
20.
The reaction of tritordeum and its Hordeum chilense and Triticum spp. parents to common bunt incited by Tilletia tritici were determined in field experiments. H. chilense accessions were very resistant, and durum wheats exhibited high to moderate levels of resistance. Conversely, bread wheats were highly susceptible. Resistance from H. chilense was expressed in the amphiploids, although the level of resistance was partially diluted at higher ploidy levels. Hexaploid tritordeums were immune to the disease; some infection was observed among the octo-ploids but at much lower levels than in their respective wheat parents. 相似文献