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81.
J. Lage B. Skovmand R. J. Peña S. B. Andersen 《Genetic Resources and Crop Evolution》2006,53(5):955-962
The wild diploid goat grass (Aegilops tauschii Cosson), and the cultivated tetraploid emmer wheat (Triticum turgidum L. subsp. dicoccon (Schrank) Thell.) may be important sources of genetic diversity for improving hexaploid bread wheat (Triticum aestivum L.). Through interspecific hybridization of emmer wheat and Ae. tauschii, followed by chromosome doubling, it is possible to produce homozygous synthetic hexaploid wheat. Fifty-eight such synthetic
hexaploids were evaluated for grain quality parameters: grain weight, length, and plumpness, grain hardness, total protein
content, and protein quality (SDS-Sedimentation volume, SDS-S). Most synthetics showed semi-hard to hard grain texture. Results
showed significant genetic variation among the synthetic hexaploids for protein content, SDS-S values, and grain weight and
plumpness. Quality measurement values of synthetic hexaploids were regressed on corresponding values of the emmer wheat parents.
With this offspring-parent regression, protein content and SDS-S values explained 8.7 and 28.8%, respectively, of the variation
among synthetics, indicating a significant contribution from the emmer wheat parents for these traits. The synthetic hexaploids,
in general, had significantly higher protein content (15.5%, on average) and longer grains than ‘Seri M82’, the bread wheat
control (13.1% protein content). Synthetics with SDS-S values and grain weights higher than those of ‘Seri M82’ were also
identified. Protein content among synthetics showed significantly negative correlations with grain weight and plumpness, but
no correlation with SDS-S values. Despite these negative correlations, 10 superior synthetic hexaploid wheats, derived from
nine different emmer wheat parents and with above average levels of protein content, SDS-S values, and either grain weight
or plumpness, were identified. This study shows that genetic variation for quality in tetraploid emmer wheat can be transferred
to synthetic hexaploid wheats and combined with plump grains and high grain weight, to be used for bread wheat breeding. 相似文献
82.
Hojjatollah Saeidi Mohammad Reza Rahiminejad Sadeq Vallian J. S. Heslop-Harrison 《Genetic Resources and Crop Evolution》2006,53(7):1477-1484
Microsatellite markers were used to analyse the biodiversity of 57 accessions of different subspecies and varieties of wild
Aegilops tauschii (2n = 2x = 14; D genome) collected across the major areas where it grows in Iran. Levels of diversity were high, with numbers of alleles
averaging 7.3 (ranging up to 12) and polymorphism information contents averaging 0.6591. One accession was notably more similar
to two of the D genome in hexaploid wheats (Triticum aestivum) used as outgroups. Within the Ae. tauschii accessions, no markers were characteristic for taxa or geographical origin, suggesting high gene flow between the subspecies
and varieties, although some groupings, which could be related to geographical origin, were evident. This survey demonstrates
the high diversity present in wild goatgrass in Iran, and indicates that there is value in sampling for useful genes for wheat
breeding. 相似文献
83.
T. A. Pshenichnikova I. F. Lapochkina L. V. Shchukina 《Genetic Resources and Crop Evolution》2007,54(2):287-293
The genetic control of morphological characters and gliadin composition was studied in two bread wheat lines with introgressed
segments from Aegilops speltoides Tausch. It was found that the transferred trait of leaf hairiness is controlled by one dominant gene, non-allelic to the
known gene, Hl1. It was localized in 7B chromosome. Whole plant non-glaucousness is under the control of an inhibitor gene, allelic to the
gene W1I of wheat located on chromosome 2B. This gene was found to be epistatic to the gene controlling spike waxlessness. The introgressed
gene for spike glume color was found to be allelic to the Rg1 gene located on 1BS of common wheat, but it was linked with another allele of the gliadin locus Gli-B1. 相似文献
84.
Resistance to stripe rust (caused by Puccinia striiformis Westend.) of 34 Triticum turgidum L. var.durum, 278 T. tauschii, and 267 synthetic hexaploid wheats (T. turgidum x T. tauschii) was evaluated at the seedling stage in the greenhouse and at the adult-plant stage at two field locations. Mexican pathotype 14E14 was used in all studies. Seedling resistance, expressed as low infection type, was present in all three species. One hundred and twenty-eight (46%) accessions of T. tauschii, 8 (23%) of T. turgidum and 31 (12%) of synthetic hexaploid wheats were highly resistant as seedlings. In the field tests, resistance was evaluated by estimating area under disease progress curve (AUDPC). Synthetic hexaploid wheats showed a wide range of variability for disease responses in both greenhouse and field tests, indicating the presence of a number of genes for resistance. In general, genotypes with seedling resistance were also found to be resistant as adult plants. Genotypes, which were susceptible or intermediate as seedlings but resistant as adult plants, were present in both T. turgidum and the synthetic hexaploids. Resistances from either T. turgidum or T. tauschii or both were identified in the synthetic hexaploids in this study. These new sources of resistance could be incorporated into cultivated hexaploid wheats to increase the existing gene pool of resistance to stripe rust. 相似文献
85.
At the IPK Gatersleben a series of 85 bread wheat (T. aestivum)/goatgrass (Aegilops tauschii) introgression lines was developed recently. Based on the knowledge that chromosome 7D of this particular Ae. tauschii is a donor of resistance to septoria tritici blotch (Mycosphaerella graminicola), a sub-set of thirteen chromosome 7D introgression lines was investigated along with the susceptible recipient variety ‘Chinese
Spring’ (CS) and the resistant donor line ‘CS (Syn 7D)’. The material was inoculated with two Argentinian isolates of the
pathogen (IPO 92067 and IPO 93014) at both the seedlings (two leaf) and adult (tillering) stages at two locations over 2 years
(2003, 2004). The resistance was effective against both isolates and at both developmental stages, and the resistance locus
maps to the centromeric region of chromosome arm 7DS. On the basis of its relationship with the microsatellite marker Xgwm44, it is likely that the gene involved is Stb5. Stb5 is therefore apparently effective against M. graminicola isolates originating from both Europe and South America. 相似文献
86.
The Acph1 locus of Aegilops tauschii encodes a new electrophoretically ‘fast’ acid phosphatase, whose allelic variation could well be involved in intraspecies differentiation. Genetic mapping via microsatellite (simple sequence repeat) analysis revealed that Acph1 is tightly linked with the marker Xgwm157 near the centromere region of chromosome 2. 相似文献
87.
S. S. Maan 《Euphytica》1977,26(3):601-613
Summary
Triticum aestivum L. em Thell. (2n=42; AABBDD), and T. durum
Desf. (2n=28; AABB) genomes were substituted into the cytoplasms of Aegilops mutica
Boiss. (2n=14; MtMt), Ae. heldreichii
Holzm. (2n=14; MM), Ae. uniaristata
Vis. (2n=14; MuMu), and Ae. ovata L. (2n=28; CuCuMoMo), to identify the M-genome diploid cytoplasm donor of Ae. ovata. Substitution of the T. durum genome into Ae. uniaristata cytoplasm resulted in a large proportion of shriveled inviable seeds. A few plump viable seeds were obtained all of which produced male-sterile plants having one univalent or telocentric chromosome from Ae. uniaristata. The T. aestivum plants having Ae. uniaristata or Ae. mutica cytoplasms were fertile. However, Ae. mutica was similar to Ae. ovata in the induction of delayed maturity and tall robust growth habit to the T. durum and T. aestivum plants. Cytoplasms of the other C- and M-genome diploids Ae. umbellulata
Zhuk. (2n=14; CuCu) and, Ae. heldreichii (2n=14; MM) earlier had been shown to differ from that of Ae. ovata. Therefore, Ae. mutica is the most likely cytoplasm and M-genome donor to Ae. ovata. 相似文献
88.
Penko Spetsov Dominique Mingeot Jean Marie Jacquemin Krassiana Samardjieva Elena Marinova 《Euphytica》1997,93(1):49-54
Winter hexaploid wheat (Triticum aestivum L.) was crossed with Aegilops variabilis to transfer resistance to powdery mildew into wheat. Following two backcrosses to wheat and from 5 to 9 generations of selfing, several disomic addition and substitution lines of hexaploid wheat resistant to the mildew pathogen were isolated. A pair of short satellited chromosomes was always observed in the resistant lines. Further evidence utilizing as markers for homoeologous group 1 HMW glutenin subunits and DNA hybridization with probe pGBX 3076 showed that an alien substitution involved this homoeologous group. 相似文献
89.
By crossing Aegilops mutica with Triticum dicoccum as a bridge species and backcrossing with common wheat as a recurrent pollen
parent, male sterile alloplasmic line(s) were produced. In progeny of the crosses, a self fertile plant with 42 chromosomes
was selected and named R 20. From this plant several lines that possessed Rf (fertility restoring) genes and/or powdery mildew
resistant genes were obtained. Apparently, the system of sterility-fertility of pollen can be applied for hybrid wheat production.
In addition, the disease resistance may be used in breeding. The male fertile lines possessed one or more Ae. mutica sat-chromosome(s),
which show the ability to suppress the nucleolar organizing regions of chromosomes 1B and 6B of common wheat. The relation
between the sat-chromosomes and male fertility restoration is not yet clear.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
90.
Summary Accession No. 1 of Aegilops variabilis has complete resistance to the root knot nematode, Meloidogyne naasi. F2 segregation in a cross between this and two susceptible accessions showed that one dominant gene named Rkn-mn1 prevented development of galls on the roots and consequently of female nematodes. The study of the numbers of females in galls on the F2 plants allowed detection of a recessive gene, Rkn-mnAv, suppressing development of J2 larvae into females. The presence of Rkn-mnAv also resulted in a decrease of the level of galling. Rkn-mn1 has already been introduced into wheat. The interest in transferring also Rkn-mnAv is discussed in relation to extending durability of the nematode resistance. 相似文献