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1.
The greenbug, Schizaphis graminum(Rondani), the Russian wheat aphid, Diuraphis noxia (Mordvilko), and the bird cherry oat aphid, Rhopalosiphum padi(L.), annually cause several million dollars worth of wheat production losses in Europe and the United States. In this study,
Triticum and Aegilops accessions from the Czech Research Institute of Crop Production and the Kansas State University Wheat Genetic Resources Center
were evaluated for resistance to these aphids. Accessions with aphid cross-resistance were examined for expression of the
antibiosis, antixenosis, and tolerance categories of resistance. Aegilops neglecta accession 8052 exhibited antibiotic effects toward all three aphids in the form of reduced intrinsic rate of increase (rm). The rm of greenbug (biotype I) on Ae. neglecta 8052 was significantly lower than that of greenbugs on plants of the susceptible U. S. variety Thunder bird. The rm of Russian wheat aphids was significantly lower on foliage of both Ae. neglecta 8052 and T. araraticum accession 168 compared to Thunderbird. The rm values of bird cherry oat aphids fed both Ae. neglecta 8052 and T. araraticum 168 were also significantly lower than those fed the susceptible accession T. dicoccoides 62. Neither Ae. neglecta 8052 or T. araraticum 168 exhibited tolerance to either greenbug biotype I or Russian wheat aphid. Preliminary data suggest that T. araraticum 168 may also possess tolerance to bird cherry oat aphid. New genes from Ae. neglecta 8052 and T. araraticum 168 expressing aphid antibiosis can be used to develop multiple aphid resistant wheat in the U. S. and Central Europe.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
2.
Wheat pre-breeding using wild progenitors 总被引：6，自引：1，他引：6
J. J. Valkoun 《Euphytica》2001,119(1-2):17-23
To facilitate the use of wheat wild relatives in conventional breedingprograms, a wheat pre-breeding activity started at ICARDA in 1994/1995season. Preliminary results of gene introgression from wild diploidprogenitors, Triticum urartu, T. baeoticum, Aegilops speltoides andAe. tauschii and tetraploid T. dicoccoides are described. Crosseswith wild diploid Triticum spp. yielded high variation in plant andspike morphology. Synthetic hexaploids were produced from crosses of alocal durum wheat landrace `Haurani' with two Ae. tauschiiaccessions. Both Ae. tauschii accessions carry hybrid necrosis allelesthat gave necrotic plant phenotypes in crosses with some bread wheats.Backcross progenies with agronomical desirable traits, i.e. high spikeproductivity, short plant stature, earliness, drought tolerance and highproductive tillering, were identified in crosses of durum wheat with wild Triticum spp. and in a cross of one of the hexaploid synthetics with alocally adapted bread wheat cv. `Cham 6'. Resistance to yellow rust wasfound in durum wheat crosses with the three wild Triticum spp. andAe. speltoides and leaf rust resistance was identified in crosses withT. baeoticum and Ae. speltoides. The results show that wheatimmediate progenitors may be a valuable and readily accessible source ofnew genetic diversity for wheat improvement. 相似文献
3.
Synthetic hexaploid wheats are of interest to wheat breeding programs, especially for introducing new genes that confer resistance
to biotic and abiotic stresses. A group of 54 synthetic hexaploid wheats derived from crosses between emmer wheat(Triticum dicoccum, source of the A and B genomes) and goat grass (Aegilops tauschii, D genome donor) were investigated for genetic diversity. Using the AFLP technique, dendrograms revealed clear grouping according
to geographical origin for the T. dicoccum parents but no clear groups for the Ae. tauschii parents. The geographical clustering of the T. dicoccum parents was also reflected in the dendrogram of their derived synthetic hexaploids. Diversity of the T. dicoccum parents and their derived synthetic hexaploids was further evaluated by measuring 18morphological and agronomic traits on
the plants. Clustering based on morphological and agronomic data also reflected geographical origin. However, comparison of
genetic distances obtained from AFLP and agronomic data showed no correlation between the two diversity measurements. Nevertheless,
similarities among major clusters with the two systems could be identified. Based on percentage of polymorphic markers, the
synthetic hexaploids had a considerably higher level of AFLP diversity (39%) than normally observed in cultivated hexaploid
wheat (12–21%). This suggests that synthetic hexaploid wheats can be used to introduce new genetic diversity into the bread
wheat gene pool.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
4.
Wheat (Triticum aestivum L.) is strictly a self‐pollinated crop, where hybrid breeding requires well‐characterized cytoplasmic male sterile (CMS) lines. The CMS has mostly been developed by substituting nuclear genome of wheat into the cytoplasm from wild relatives. Molecular characterization of 90 genotypes including 82 CMS lines originating from five different species, namely Aegilops speltoides, Ae. kotschyi, Ae. variabilis, Triticum araraticum and T. timopheevii, and eight popular varieties was carried out. Consequently, a set of 25 microsatellite markers specific to chloroplast (cpSSRs) were designed and successfully validated for specificity of amplification. A total of 15 cpSSRs (60%) were found polymorphic, of which three cpSSRs (TaCM7, TaCM8 and TaCM11) in genic region and twelve cpSSRs were located in intergenic region. Phylogenetic analysis of genotypes using cpSSRs revealed two major groups well in accordance with respective origin. A set of cpSSRs and phylogeny of CMS belonging to different origins developed, which will be helpful for the improvement in CMS system in wheat. The genic cpSSRs can be used for the allele mining and evolutionary studies. 相似文献
5.
A total of 259 accessions of wild Triticum species originating from different countries, along with 91 triticale (6×)× bread wheat true-breeding derivatives, two bread wheat, and three triticale cultivars were screened for resistance to the Russian wheat aphid, a serious insect pest of the wheat crop. Twenty-four entries with low damage ratings on the basis of amount of leaf rolling and leaf chlorosis were retested along with resistant and susceptible controls. On the basis of leaf roll damage ratings, eight entries including four Triticum monococcum var. boeoticum (T. boeoticum), one T. monococcum var. monococcum (T. monococcum), two T. timopheevii var. araraticum (T. araraticum), and one triticale cultivar were significantly superior to ‘Karl’ (susceptible control) wheat. Among these, four accessions — three T. boeoticum and one T. araraticum— were significantly superior to all other entries and were equal to the resistant control (PI 372129) in resistance rating based on leaf rolling and leaf chlorosis (except T. boeoticum TA 202). The leaf chlorosis damage rating of all accessions were significantly lower than that of the susceptible check. 相似文献
6.
In order to reveal the molecular genetic diversity of wheat wild relatives, an AFLP analysis was conducted with 16 accessions
of five Triticum andAegilops species originating from the Near East. Variation within population was studied with at least seven individuals per accession.
Four primer combinations were used for selective amplification. Based on the scored bands, we estimated percentage of polymorphic
bands, 1 – proportion of shared bands (1-psb) and nucleotide diversity (π). Of the five species used in this study, Ae.
speltoides had the highest level of `within population' variation. This species had also the highest value of the variation among populations.
As for Triticum species, the level of variation within population was low in diploid species (T. urartu and T. boeoticum),whereas two tetraploid species (T. dicoccoides and T. araraticum) had relatively high levels of variation within population. While the two diploid Triticum indicated a clear interspecific divergence, the two tetraploid wild wheats were not clearly divergent in this study. The
variance portioning analysis indicated that the variation detected for diploid Triticum species was mainly composed of `between species' variation, on the other hand that for tetraploid Triticum was mostly composed of `within population' variation. In conclusion, AFLP analysis reveals molecular variation in all accessions
used in this study, suggesting a potential genetic diversity of the wheat wild relatives in natural populations. These results
have implications for the design of strategies to maintain genetic diversity within genebank collections.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
7.
Summary Resistance to septoria nodorum blotch in Triticum monococcum, T. tauschii, T. timopheevii, T. dicoccum and T. durum was evaluated on plants at the three-leaf stage in greenhouse tests. A high frequency of resistant genotypes was found in T. monococcum, T. tauschii and T. timopheevii, but not in T. dicoccum and T. durum. The resistance of F1 plants of crosses of resistant T. monococcum (PI 289599) and T. timopheevii (PI 290518) accessions with susceptible common wheat cv. Park and durum wheat cv. Wakooma, respectively, was evaluated on the basis of percentage leaf necrosis, lesion number, lesion size and incubation period. No dominance was found for long incubation period, but various dominance relationships occurred for low percentage leaf necrosis, low lesion number and small lesion size, depending on the cross. Multiple regression analysis showed that lesion number contributed more to percentage leaf necrosis than lesion size or incubation period. Resistance to septoria nodorum blotch was transferred successfully from T. timopheevii to cultivated durum wheat. Resistant BC1F7 lines, recovered from the T. timopheevii (PI 290518) × Wakooma cross, showed normal chromosome behaviour at meiosis (14 bivalents) and were self-fertile. However, an effective level of resistance was not recovered in lines derived from the other interspecific crosses. 相似文献
8.
Variability of high molecular weight glutenin subunits (HMW-GS) was studied in198 accessions of Ae. Tauschii (2n=2x=14, DD) by sodium dodecyl sulphate(SDS-PAGE) and acid polyacrylamide gel electrophoresis (A-PAGE) and capillary electrophoresis
(CE). A high allelic variation of HMW-GS, including some novel x- and y-type subunits and variable subunit combinations were
observed. One accession(TD159) showed a x-type null form. The results by A-PAGE analysis revealed that the subunits Dx5
t and Dy10
t encoded by Glu-D
t
1 locus in Ae. tauschii were different in relative mobilities in comparison with the subunits Dx5 and Dy10 found in bread wheats, whereas they had
the same mobilities, respectively, when separated by SDS-PAGE. The higher resolution of Ae. tauschii HMW-GS separated by CE method showed two clear peaks in accordance with x- and y-type subunits, respectively,except the accession
TD151 which possessed only subunit Dy12.1*t. The electro elution time of the x-type and y-type subunits were about 13–14 and 7–8minutes, respectively. Characterization
of wheat HMW-GS was facilitated by using CE which provides high resolution and increases the speed of analysis in conjunction
with the traditional gel electrophoretic methods. A total of 42HMW-GS alleles were identified, among which were several alleles
not presently detected in bread wheats. Hence Ae. tauschii is potentially a valuable genetic resource for quality improvement of bread wheat.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
9.
Genome-specific markers of tetraploid wheats and their putative diploid progenitor species 总被引：4，自引：0，他引：4
The objective of this study was to isolate genome‐specific markers from the genomes of tetraploid wheats and the putative donor diploid species on the basis of random amplified polymorphic DNA analysis followed by cross‐hybridization. Twenty different Triticum and Aegilops species and accessions were analysed by polymerase chain reaction (PCR) using 30 random primers. The polymorphic PCR fragments were then isolated, labelled and used in cross‐hybridization screenings. The hybridization results established that one marker was specific to the Ae. speltoides S genome, two to the A genome, one to the B genome and five to the G genomes of polyploid species (and to the genomes of the corresponding progenitor species). Four markers were identified that were specific to both the B and G genomes. Analysis of the Triticum and Aegilops species and accessions supported the notion that Ae. speltoides is more closely related to the B and G genomes of polyploid wheat species than were other members of the Sitopsis section. The data also indicated that the B and G genomes had originated from different accessions of Ae. speltoides. 相似文献
10.
Cenci Alberto D'Ovidio Renato Tanzarella Oronzo Antonio Ceoloni Carla Pasquini Marina Porceddu Enrico 《Euphytica》2003,130(2):177-183
The distal region of the short arm of chromosome 3S from Aegilopslongissima, which carries the powdery mildew resistance gene Pm13, was introgressed into common wheat. Due to suppression of recombination between this region and corresponding wheat homoeologous
segments, a possible strategy to construct a genetic map around the Pm13 gene was based on crosses between a wheat addition line carrying the Ae.longissima 3S chromosome and the corresponding 3S addition lines of Ae.searsii and Ae. variabilis. The efficiency of this strategy was evaluated by scoring recombination frequencies inprogenies derived from these crosses.
Recombination between 3S chromosomes fromAe. searsii and Ae. longissimawas very low, whereas 26.5% recombinant alien chromosomes were obtained from the cross involving the Ae. variabilisand Ae. longissima 3S addition lines. These data were used to construct a3S chromosome map that resulted largely colinear to the consensus map
of the homoeologous group 3 of wheat.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
11.
It was recently shown that allopolyploidy brings novel epistatic interactions to genes belonging to different genomes. However, systematic studies of the phenotypic relationships between synthetic hexaploid wheats and their parental lines have not been conducted. In this study, 27 synthetic hexaploid wheats were produced by crossing the tetraploid wheat cultivar ‘Langdon’ with 27 accessions of Aegilops tauschii. Variations in 20 morphological and flowering traits were analysed in both the synthetic wheat lines and the parental Ae. tauschii accessions. The 20 traits exhibited large variations in the wheat lines. For many of the traits, the degree of variation in the parental accessions was reduced in the hexaploid derivatives. Principal component analysis of floret‐related traits divided the Ae. tauschii accessions into two subspecies, ssp. tauschii and ssp. strangulata, but this parental pattern of subspecific division was not detectable in the hexaploids. Our results suggest that the ‘Langdon’ genome may have an alleviating effect on the expression of D‐genome‐derived variations in derived synthetics. 相似文献
12.
Summary A simple method is proposed to distinguish hexaploid (Triticum aestivum L.) from tetraploid (Triticum turgidum L., durum wheat) cultivated wheats on the basis of peroxidase isozymes coded by genome D. It can also be used as a first step to detect possible contamination by tetraploid genotype mixtures. The peroxidase patterns of endosperm and of embryo plus scutellum found among 349 entries of a durum wheat world basis collection are shown. 相似文献
13.
C. M. Konik-Rose S. Rahman R. Appels R. Moss G. McMaster D. R. Marshall F. L. Stoddard 《Euphytica》2009,167(2):203-216
Greater variability in starch properties is found in lower ploidy wheats than in commercial hexaploid wheats. This paper reports
on the starch properties and variability in granule bound starch synthase (GBSS) loci of 17 diploid (Aegilops tauschii) and 12 tetraploid (durums) potential progenitors of wheat, compared with 29 synthetic hexaploid wheats produced from such
progenitors. Starch properties examined were granule size distribution, swelling power, amylose content, gelatinisation and
amylose-lipid dissociation properties. A PCR screening method was able to detect the presence or absence of each of the three
GBSS genes. It also detected polymorphisms in eight diploids and nine hexaploids, all displaying the same 25 bases deletion
in the D genome allele of GBSS. Two tetraploids and five hexaploids were null 4A for GBSS. There was little difference in
the amylose contents and amylose-lipid dissociation peak temperatures of the synthetic hexaploids and the lower ploidy wheats.
The synthetic hexaploids showed intermediate swelling power values with the durums giving the highest swelling powers. The
durums also had higher B granule contents than the A. tauschii accessions, but not as high as the synthetics. However, the A. tauschii samples gave the highest gelatinisation peak temperatures. The presence of the null 4A mutation was positively correlated
with swelling power, amylose content and DSC measurements. The new smaller D genome allele of GBSS was associated with slightly
higher swelling power. These results confirm the value of wheat progenitor lines as sources of new starch properties for hexaploid
wheat.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
14.
Relation between wheat-rye crossability and seed set of common wheat after pollination with other species in the Hordeae 总被引：1，自引：0，他引：1
Summary Cultivars of common wheat (Triticum aestivum L. em. Thell.) of high wheat-rye (Secale cereale L.) crossability set more seed with pollen of other related species than did wheats of low wheat-rye crossability. This was found to be true for pollen parents from the genera Triticum, Aegilops, Secale, Agropyron and Elymus. 相似文献
15.
Hydroxamic acid content of triticum species 总被引：2，自引：0，他引：2
Hermann M. Niemeyer 《Euphytica》1988,37(3):289-293
Summary Fifty-five accessions of Triticum species were analyzed for content of hydroxamic acids (Hx), a natural resistance factor against various organisms. Hx were found in all accessions analyzed. Extreme values were found in wild diploid species: highest in T. speltoides (16.0 mmol/kg fr. wt) and lowest in T. tauschii (0.21). Modern polyploid wheats sharing the same genome did not show substantial variations in Hx levels. The data suggest possible sources of high Hx levels for wheat breeding programs. 相似文献
16.
Summary Expression of 17 rye traits in 24 bread wheat x rye and 8 durum wheat x rye crosses was studied, using a self-compatible, homozygous, dwarf rye. Rye showed epistasis for hairiness on the peduncle in all the crosses of Triticum aestivum and T. durum wheats with rye. Dark greenness of leaves of rye was expressed in all the durum wheat x rye and in some of the bread wheat x rye crosses. Similarly, absence of auricle pubescence, a rye trait, was expressed in most of the durum wheat x rye crosses but not in the bread wheat x rye crosses, indicating the presence of inhibitors for these traits frequently on the D genome and rarely on the A and/or B genome of wheat. Most of the wide hybrids resembled rye fully or partially for intense waxy bloom on the leaf-sheath and for the absence of basal underdeveloped spikelets. Similarly, most of the amphihaploids resembled rye for the anthocyanin in the coleoptile, stem and node. The presence of some inhibitors on A and/or B genome of wheat was indicated in some of the wheat genotypes for the expression of rye traits viz. intense waxy bloom, anthocyanin in node and absence of basal underdeveloped spikelets. Enhancement in the level of expression of the intensity and length of bristles on the mid-rib of the glume of the hybrids might be due to wheat-rye interaction. Less number of florets/spikelet as in rye showed variable expression in different wheat backgrounds. Some other rye traits like absence of auricles, terminal spikelet and glume-awn were not expressed in the wheat background. The expression of some of the rye genes might have been influenced by their interaction with Triticum cytoplasm and/or the environment. 相似文献
17.
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
18.
M. Aghaee-Sarbarzeh M. Ferrahi S. Singh H. Singh B. Friebe B.S. Gill H.S. Dhaliwal 《Euphytica》2002,127(3):377-382
Leaf and stripe rusts are severe foliar diseases of bread wheat. Recently, chromosomes 5Mg from the related species Aegilops geniculata that confers resistance to both leaf and stripe rust and 5Ut from Ae. triuncialis conferring resistance to leaf rust have been transferred to bread wheat in the form of disomic DS5Mg(5D) and DS5Ut(5A) chromosome substitution lines. The objective of this study was to shorten the alien segments in these lines using Ph
I-mediated, induced homoeologous recombination. Putativerecombinants were evaluated for their rust resistance, and by genomic
in situ hybridization and microsatellite analyses. One agronomically useful wheat-Ae. geniculata recombinant resistant to leaf and stripe rust was identified that had only a small terminal segment of the 5MgL arm transferred to the long arm of an unidentified wheat chromosome. This germplasm can be used directly in breeding programs.
Only one leaf rust-resistant wheat-Ae. triuncialis recombinant, which consists of most of the complete 5Ut chromosome with a small terminal segment derived from 5AS, was identified. This germplasm will need further chromosome engineering
before it can be used in wheat improvement.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
19.
An interspecific cross was made to transfer leaf rust and stripe rust resistance from an accession of Aegilops ovata (UUMM) to susceptible Triticum aestivum (AABBDD) cv. WL711. The F1was backcrossed to the recurrent wheat parent, and after two to three backcrosses and selfing, rust resistant progenies were
selected. The C-banding study in a uniformly leaf rust and stripe rust resistant derivative showed a substitution of the 5M
chromosome of Ae. ovata for 5D of wheat. Analysis of rust resistant derivatives with mapped wheat microsatellite makers confirmed the substitution
of 5M for 5D. Some of these derivatives also possessed one or more of the three alien translocations involving 1BL, 2AL and
5BS wheat chromosomes which could not be detected through C-banding. A translocation involving 5DSof wheat and the substituted
chromosome 5M of Ae. ovata was also observed in one of the derivatives. Susceptibility of this derivative to leaf rust showed that the leaf rust resistance
gene(s) is/are located on short arm of 5M chromosome of Ae. ovata. Though the Ae. ovatasegment translocated to 1BL and 2AL did not seem to possess any rust resistance gene, the alien segment translocated to 5BS
may also possess gene(s) for rust resistance. The study demonstrated the usefulness of microsatellite markers in characterisation
of interspecific derivatives.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献