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1.
Summary Wild relatives of common wheat, Triticum aestivum, and related species are an important source of disease and pest resistance and several useful traits have been transferred from these species to wheat. C-banding and in situ hybridization analyses are powerful cytological techniques allowing the detection of alien chromatin in wheat. C-banding permits identification of the wheat and alien chromosomes involved in wheat-alien translocations, whereas genomic in situ hybridization analysis allows determination of their size and breakpoint positions. The present review summarizes the available data on wheat-alien transfers conferring resistance to diseases and pests. Ten of the 57 spontaneous and induced wheat-alien translocations were identified as whole arm translocations with the breakpoints within the centromeric regions. The majority of transfers (45) were identified as terminal translocations with distal alien segments translocated to wheat chromosome arms. Only two intercalary wheat-alien transloctions were identified, one induced by radiation treatment with a small segment of rye chromosome 6RL (H25) inserted into the long arm of wheat chromosome 4A, and the other probably induced by homoeologous recombination with a segment derived from the long arm of a group 7 Agropyron elongatum chromosome with Lr19 inserted into the long arm of 7D. The presented information should be useful for further directed chromosome engineering aimed at producing superior germplasm.Contribution No. 96-55-J from the Kansas Experimental Station, Kansas State University, Manhattan, KS 66506-5502, USA.  相似文献   

2.
Wheat-barley translocations were identified by genomicin situ hybridization (GISH) in backcross progenies originating from in vitro regenerated wheat (Triticum aestivum L. cv. Chinese Spring) × barley (Hordeum vulgare L. cv. Betzes) hybrids. The regenerated hybrids were pollinated with the wheat line Martonvásári 9 kr1. Five translocated wheat-barley chromosomes were recovered among 51 BC2F2 progeny from the in vitro regenerated wheat × barley hybrids. All were single breakpoint translocations with the relative positions of the breakpoints ranging from the centromere to about 0.8 of the relative arm length. Of the four translocations with intercalary breakpoints, three were transfers of terminal barley segments to wheat chromosomes; one was a transfer of a terminal wheat segment to a barley chromosome. Because of the absence of diagnostic N-bands, the identity of three barley segments could not be determined; in one translocation the barley chromosome involved had a NOR so it must have been 5H or 6H, and the centric translocation was 4HS.2BL. Following selfing, homozygotes of four translocations were selected. The experiment suggests that in vitro culture conditions are conducive for major genome rearrangements in wheat-barley hybrids. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

3.
A genome specific DNA sequence that detects Secale africanum chromatin incorporated into wheat was developed in this study. Random amplified polymorphic DNA (RAPD) analysis was used to search for genome specific DNA sequences of S. africanum in lines, R111, “mianyang11” (MY11) and wheat-rye 1RS/1BL translocations R25 and R57. A high copy rye-specific DNA segment pSaD15940 of the S. africanum genome was obtained. The sequence of pSaD15 did not show any significant homology to other reported sequences in databases and it is therefore a new repetitive sequence of Secale. PCR primers were designed for pSaD15940, which amplify a clear 887 bp fragment in S. africanum but not in any wheat. The primers also amplified an 887 bp fragment in other accessions of rye, Chinese Spring-Imperial rye chromosome additions and a diverse range of material carrying different rye chromosomes or chromosomal segments. In situ hybridization showed that probe pSaD15940 was specifically hybridized throughout all rye chromosomes arms except for the terminal regions. The advantage of the rye-specific probe developed herein compared to those of previous reports is that it has been shown to be widely applicable to other Secale species. The probe will be useful as a molecular marker for the introgression of S. africanum and other rye chromosome segments into the wheat genome.  相似文献   

4.
Summary Fluorescent in situ hybridization (FISH) of DNA to plant chromosomes has proved to be a powerful cytogenetic tool. The value of fluorescent in situ hybridization of total genomic DNA (GISH) of related species is demonstrated in the determination of wheat/alien chromosome pairing in hybrids. Its use for assessing the relative merits of the various genes that affect chromosome pairing is also shown.The ability of GISH to identify the presence in wheat of whole alien chromosomes or alien chromosome segments is illustrated. The potential of FISH for detecting repeated DNA sequences, low copy sequences and single copy genes is discussed.Abbreviations FISH fluorescent in situ hybridization - GISH genomic in situ hybridization - PRINS primer-induced in situ hybridization  相似文献   

5.
Y. B. Wang  H. Hu  J. W. Snape 《Euphytica》1995,81(3):265-270
Summary Heptaploid hybrids between octoploid triticale and wheat were backcrossed as female parents with wheat to examine the rye chromosome distribution in the resultant progenies using genomic in situ hybridization (GISH). One hundred and one backcross (BC) seeds were examined and whole rye chromosome additions and substitutions, wheat/rye centric and noncentric translocations and rye telocentric chromosomes were detected. Dicentric wheat/rye translocated chromosomes were also observed. Comparisons were made with previous results on the rye chromosome distribution from male gametes of the same cross and differences were found, where in the female derived population a deficit of plants with more than two rye chromosomes was apparent relative to the anther derived population.  相似文献   

6.
×Tritordeum (Ascherson et Graebner, an amphiploid between Triticum turgidum conv. durum and Hordeum chilense), and chromosome substitution lines of tritordeum where chromosomes 2 H ch or 3 H ch H. chilense were replaced with chromosome 2 D of T. aestivum or 3 H v chromosome of H. vulgare, respectively, were used to assess the effect of specific chromosomes on the rachis. ×Tritordeum has brittle rachis while the 2 D(2 H ch) and 3 H v (3 H ch) substitution lines have non-brittle rachis. Both lines also have compact spikes, a character highly desirable for the improvement of tritordeum threshability. Different combinations of 2 D and 3 H v translocations were developed in tritordeum. In this article we present information on the identification and characterisation of all these introgression lines by the fluorescent in situ hybridisation.  相似文献   

7.
Previous studies showed that a T. aestivum-H. villosa disomic substitution line DS4V(4D) showed a high level of resistance to wheat spindle streak mosaic virus (WSSMV). By crossing DS4V(4D) with the common wheat variety Yangmai #5, plants were obtained that were double monosomic for chromosomes 4V and 4D. Univalents are prone to misdivision at the centromere, and fusion of the derived telocentric chromosomes leads to the production of Robertsonian whole-arm translocations. We screened the progenies of such double monosomic plants by C-banding and genomic in situ hybridization and identified one compensating translocation where the short arm of 4V was translocated to the long arm of 4D of wheat, T4VS⋅4DL. RFLP analysis using the group-4 specific probe BCD110 was used to confirm the translocation. The T4VS⋅4DL translocation stock, accessioned as NAU413, is highly resistant to WSSMV and is also of good agronomic type. The WSSMV resistance gene located on 4VS was designated Wss1.  相似文献   

8.
Summary Fluorescent in situ hybridization (FISH) has been used to assess the occurrence and frequency of wheat-alien chromosome pairing in a wheat/Thinopyrum bessarabicum hybrid and in wheat/rye hybrids with different levels of chromosome pairing by examining pollen mother cells at metaphase I of meiosis. The use of FISH to identify the presence and size of alien chromatin in a wheat background is also demonstrated.The value of FISH as an aid to the introgression of alien genetic variation into wheat is discussed.Abbreviations FISH fluorescent in situ hybridization - GISH genomic in situ hybridization - PRINS primer-induced in situ hybridization  相似文献   

9.
Two amphiploids, AF-1(Triticum aestivum L. cv. Anyuepaideng–Secale africanum Stapf.) and BF-1 (T. turgidum ssp. carthlicum–S. africanum), were evaluated by chromosomal banding and in situ hybridization. The individual S. africanum chromosomes were identified in the BF-1 background by sequential C-banding and genomic in situ hybridization (GISH), and were distinguishable from those of S. cereale, because they exhibited less terminal heterochromatin. Fluorescence in situ hybridization (FISH) using the tandem repeat pSc250 as a probe indicated that only 6Ra of S. africanum contained a significant hybrid signal, whereas S. cereale displayed strong hybridization at the telomeres or subtelomeres in all seven pairs of chromosomes. Extensive wheat–S. africanum non-Robertsonian translocations were observed in both AF-1 and BF-1 plants, suggesting a frequent occurrence of chromosomal recombination between wheat and S. africanum. Moreover, introgression lines selected from the progeny of wheat/AF-1 crosses were resistant when field tested with widely virulent strains of Puccinia striiformis f. sp. tritici. Three highly resistant lines were selected. GISH and C-banding revealed that resistant line L9-15 carried a pair of 1BL.1RS translocated chromosomes. This new type of S. africanum derived wheat–Secale translocation line with resistance to Yr9-virulent strains will broaden the genetic diversity of 1BL.1RS for wheat breeding.  相似文献   

10.
Pre-harvest sprouting (PHS) reduces the quality of wheat (Triticum aestivum L.) and the economic value of the grain. The objective of this study was to evaluate the diversity of the Viviparous-1B (Vp-1B) gene associated with PHS tolerance in a collection of 490 widely grown winter wheat varieties from central and northern Europe. Four alleles of Vp-1B were found in the wheat varieties tested, three of which (Vp-1Ba, Vp-1Bb and Vp-1Bc) had previously been identified in Chinese wheat varieties. The fourth was a new allele which had a 25-bp of deletion in the third intron region compared with the nucleotide sequence of Vp-1Ba, and was designated as Vp-1Bd. The frequencies of different alleles in this set of European wheat germplasm were: Vp-1Ba (54%) > Vp-1Bc (21%) > Vp-1Bd (20%) > Vp-1Ba + c (4%) > Vp-1Bb (1%), with Vp-1Bb being present only in two French varieties, ‘Altria’ and ‘Recital’. In addition, the frequencies of the alleles differed in varieties from different European countries. For example, Vp-1Ba had the highest frequency (76%) in varieties included in the UK National List (NL), but was least frequent in the Recommended List (RL) of Sweden (19%). Similarly, Vp-1Bc was present with the highest frequency (58%) in wheat varieties from Sweden, and the lowest in UK NL varieties (8%) while Vp-1Bd had the highest frequency of 32% in German varieties, and the lowest in Sweden varieties with only 8%. The Vp-1Ba allele was present in over half of the UK wheat varieties tested but the frequency was lower in RL varieties than in NL ones. Furthermore, heterogeneities were found between Vp-1Ba and Vp-1Bc in the varieties from Sweden, Netherlands, Germany and UK.  相似文献   

11.
Detection of H. villosa chromosomes in telosomic addition and translocation lines of common wheat was undertaken using genomic in situ hybridization (GISH), C-banding techniques and polyacrylamide gels electrophoresis. The result of GISH on mitotic metaphase cells of the addition line `95039' indicated that the added telochromosomes originated from H. villosa, and it was probably 6VS or 7Vs of H. villosa according to the C-banding pattern. Furthermore, the analysis of gliadin profiles demonstrated that the telochromosome was 6VS. A pair of 1RS/1BL translocation chromosome was also found in `95039'. In addition, mitotic GISH analysis showed that the 6VS/6AL translocation chromosome remained unchanged after being transferred into new wheat background. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

12.
Summary A rapid fluorescent in situ hybridization protocol, which can be completed in one working day, has been utilised to visualize chromosome preparations of barley, chickpea, white clover, millet, rye, sugarcane, wheat, Aegilops spp. and Leymus spp. Both total genomic DNA and cloned nuclear rDNA were used as a probe. This protocol has the advantage of brevity and flexibility over more conventional approaches, and has made fluorescent in situ hybridization a routine cytological procedure.  相似文献   

13.
Liu Shubing  Wang Honggang 《Euphytica》2005,143(1-2):229-233
Among the progenies of a hybrid between common wheat Triticum aestivum L. cv. Yannong 15 and Thinopyron intermedium, plant E99018 was identified with the chromosome number 2n = 42 and stable agronomic traits. An analysis of the metaphase chromosome pairing indicated that it formed 21 bivalents but that 2 univalents were present in the F1 hybrid of this plant with common wheat. Resistance verification by race 15 and with mixed races of Blumeria graminis f. sp. tritici at the seedling and adult stages showed that at both stages, the plant was immune to powdery mildew. In situ hybridization with the genomic Th. intermedium and the St genome DNAs as probes and wheat DNA as a block has shown that it contained a pair of Th. intermedium chromosomes. On the basis of the hybridization pattern of the St genome probe to the critical chromosome, a conclusion was reached that this pair of chromosomes belonged to the E genome. Therefore, plant E99018 was a spontaneously formed substitution line. An analysis by 116 SSR markers indicated that the substituted wheat chromosome was 2D and the most likely substitution in E99018 is 2E(2D).  相似文献   

14.
Genomic in situ hybridization (GISH) and restriction fragment length polymorphism (RFLP) were used to identify the Leymus multicaulis (XXNN, 2n = 28) chromosomes in wheat-L. muliticaulis derivatives. Fifteen lines containing L. multicaulis alien chromosomes or chromosomal fragments were identified. All alien chromosomes or fragments in these 15 lines were from the X genome and none were from the N genome. Eleven L. multicaulis disomic addition lines and four translocation-addition lines were identified with chromosome rearrangements among homoeologous groups 2, 3, 6 and 7. Only homoeologous group 1 lacked rearrangements in addition or translocation chromosomes. The results revealed that translocation in non-homoeologous chromosomes widely exists in the Triticeae and therefore it is necessary to identify the alien chromosomes (segments) in a wheat background using these combined techniques. During the course of the work, probe PSR112, was found to detect X genome addition lines involving L. multicaulischromosomes. This may prove to be a valuable probe for the identification of alien chromosomes in a wheat background. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

15.
Flowering time is an important trait for the adaptation of wheat to its target environments. To identify chromosome regions associated with flowering time in wheat, a whole genome scan was conducted with five sets of field trial data on a recombinant inbred lines (RIL) population derived from the cross of spring wheat cultivars ‘Nanda 2419’ and ‘Wangshuibai’. The identified QTLs involved seven chromosomal regions, among which QFlt.nau-1B and QFlt.nau-2B were homoeologous to QFlt.nau-1D and QFlt.nau-2D, respectively. Nanda 2419, the earlier flowering parent, contributed early flowering alleles at five of these QTLs. QFlt.nau-1B and QFlt.nau-7B had the largest effects in all trials and were mapped to the Xwmc59.2–Xbarc80 interval on chromosome 1BS and the Xgwm537–Xgwm333 interval on 7BS. Most of the mapped QTL intervals were not coincident with known vernalization response or photoperiod sensitivity loci and QFlt.nau-1B seems to be an orthologue of EpsA m 1. Four pairs of loci showed significant interactions across environments in determining flowering time, all of which involved QFlt.nau-1B. These findings are of significance to wheat breeding programs.  相似文献   

16.
Genetic capacity for green plant regeneration in anther culture were mapped in a population comprising 50 doubled haploid lines from a cross between two wheat varieties ‘Ciano’ and ‘Walter’ with widely different capacity for green plant regeneration. Bulked segregant analysis with AFLP markers and composite interval mapping detected four QTLs for green plant percentage on chromosomes 2AL (QGpp.kvl-2A), 2BL (QGpp.kvl-2B.1 and QGpp.kvl-2B.2) and 5BL (QGpp.kvl-5B).The three QTLs detected on chromosome 2AL and 2BL all derived their alleles favouring green plant formation from the responsive parent ‘Ciano’.The remaining QTL on chromosome 5BL had the allele favouring green plants from the low responding parent ‘Walter’. In a multiple regression analysis the four QTLs could explain a total of 80% of the genotypic variation for green plant percentage. None of the chromosomal regions with QTLs for green plant percentage showed significant influence on either embryo formation or regeneration frequencies from the anther culture. The three major QTLs located on group two chromosomes were fixed in a second DH population derived from two parents ‘Ciano’ and ‘Benoist’,both with high capacity to produce green plants. A QTL explaining31.5% of the genetic variation for green plant formation were detected on chromosome 5BL in this cross as well. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

17.
Summary The sequential combination of C-banding and in situ hybridization techniques applied in this or in a reverse order, are used to recognize targeted chromosomal regions in cereals. Both methods are described whereby standard chromosome squash preparations are followed by: i) C-banding technique using Leishman stain and a slightly modified in situ hybridization technique using biotin-labeled DNA probes, or ii) fluorescence in situ hybridization technique and C-banding. Both approaches have been successfully used onto mitotic chromosomes of rye and wheat resulting suitable for both their identification and detection of targeted sites.  相似文献   

18.
Ear emergence time and response to vernalization were investigated in 12 alien substitution lines in which a pair of chromosomes 5A of recipient spring wheat cultivars was replaced by a pair of chromosomes 5R of Siberian spring rye ‘Onokhoiskaya’. The recipients were 12 spring cultivars of common wheat, each carrying different Vrn genes. Spring rye ‘Onokhoiskaya’ had the Sp1 (now called Vrn-R1) gene for spring growth habit located on chromosome 5R, but its expression was weaker. The Vrn-R1 gene had no effect on growth habit, ear emergence time and response to vernalization in wheat-rye substitution lines. Ears emerged significantly later in the 5R(5A) alien substitution lines than in the recipient wheat cultivars with the Vrn-A1/Vrn-B1/vrn-D1 or Vrn-A1/vrn-B1/Vrn-D1 genotypes. No difference in ear emergence time was found between most of the 5R(5A) alien substitution lines and the cultivars carrying the recessive vrn-A1 gene. The presence of the Vrn2a and Vrn2b alleles at the Vrn2 (now called Vrn-B1) locus located on wheat chromosome 5B was confirmed.The replacement of chromosome 5A by chromosome 5R in wheat cultivars ‘Rang’ and ‘Mironovskaya Krupnozernaya’, which carries the single dominant gene Vrn-A1, converted them to winter growth habit. In field studies near Novosibirsk the winter hardiness of 5R(5A) wheat–rye substitution lines of ‘Rang’ and ‘Mironovskaya Krupnozernaya’ was increased by 20–47% and 27–34%, respectively, over the recurrent parents.  相似文献   

19.
Summary The incorporation of rye (S. cereale L.) chromatin into winter wheat (T. aestivum L.) cultivars is often achieved via hybridization of unadapted wheat-rye translocation lines with adapted wheat germplasm. Identification of progenies possessing the translocated chromosome has traditionally involved phenotypic screening for the desired rye characteristics. In this study, the Giemsa N-banding technique was evaluated as a potential screening tool for detection of 1B/1R wheat-rye translocations. Five breeding lines were examined from the pedigree Aurora/2*TAM W-101. The differential banding patterns of chromosome 1B contributed by TAM W-101 and chromosome 1B/1R contributed by Aurora allowed unequivocal identification of translocation genotypes. Three of the lines were found to be heterogeneous, whereby plants were homozygous for either the normal 1B or the translocated 1B/1R chromosome. The remaining two lines were observed to be homozygous and homogeneous for the translocated 1B/1R chromosome. The implication of N-banding chromosomal analyses to wheat breeding is presented.Contribution No. J-5172, Department of Agronomy, Oklahoma Agriculture Experiment Station, Oklahoma State University, Stillwater, OK74078.  相似文献   

20.
J. Sybenga 《Euphytica》1996,89(1):143-151
Summary Cytological tester sets include series of aneuploids (nullisomics, monosomics, trisomics of different types, tetrasomies), series of rearranged chromosomes (translocations, inversions, duplications, deficiencies) and series of chromosomes recognizable by specific microscopically visible markers (C- or other banding, molecular markers). In rye, only a few (mainly tertiary and telocentric) monosomics and no viable nullisomics have been found. Several sets of primary trisomics and some telocentric sets, usually not fully complete, have been developed, but few are still available for gene localization. A few tertiary trisomics have been derived from translocation heterozygotes. Extensively used are different sets of additions of rye chromosomes to wheat. A relatively widely distributed set of marked chromosomes is the Wageningen translocation tester set, complemented with translocations from different other institutions. A disadvantage of rye translocations is insufficient heterozygote semisterility. Series of otherwise rearranged chromosomes have not been reported. Sets of lines with chromosomes conspicuously differing from the standard C-banding pattern have been obtained. Molecular markers are available for most rye chromosome, but lack of heterozygosity, necessary for classification after in situ hybridization is a restriction for use as cytological testers. In the cases of most translocations, C-banding and in situ molecular markers, each separate plant in a segregating population must be screened cytologically, whereas with aneuploid markers or with translocations having sufficient heterozygote semisterility, analyzing segregations is sufficient.  相似文献   

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