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1.
J. Sybenga 《Euphytica》1995,83(1):53-61
Summary Cytological tester sets include series of aneuploids (nullisomics, monosomics, trisomics of different types, tetrasomics), 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 afterin situ hybridization is a restriction for use as cytological testers. In the cases of most translocations, C-banding andin 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   

2.
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   

3.
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   

4.
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   

5.
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   

6.
Crosses between octoploid and hexaploid triticales have been made m breeding programs for several years, From an analysis of the progeny of such crosses where selections for an octoploid-like phenotype had been made, it was established that 149 out of 150 lines were hexaploid in chromosome number, C-banding and in situ hybridization demonstrated that all but five of the 62 lines analyzed in detail contained visible chromosomes or segments from the D genome. Only four lines had D-genome chromosome replacing rye chromosomes. All of the remaining 53 D-genome substitutions involved the replacing of wheat chromosomes from either the A or B genomes. This establishes the ease with which D-genome genes can be placed into triticale without the loss of rye chromosomes.  相似文献   

7.
Z. L. Ren    T. Lelley  G. Röbbelen 《Plant Breeding》1990,105(4):265-270
Hybrid plants with 21 pairs of wheat chromosomes and with a haploid rye genome were produced by backcrossing a primary octoploid triticale with its parental hexaploid wheat. Upon a second backcrossing or selfing, the rye chromosomes were eliminated rapidly. Added rye chromosomes, in varying numbers, affected the transmission rate of wheat chromosomes significantly. Loss of wheat chromosomes ranging from 0.06 to 0.35 per plant in different populations was observed. In these plants a remarkably high incidence of wheat/rye and rye/rye translocations occurred. Translocations were identified by using the C-banding technique. Among 837 analyzed plants 64 wheat/rye and 256 rye/rye translocations were identified. In different generations of backcrossing or selfing the frequency of wheat/rye translocations varied between 4.23 % and 14.67 %. All 14 rye chromosome arms were involved in translocations but with different frequencies. BC1F3 plants with homozygous wheat/rye translocations were isolated The results indicate that monosomic wheat/rye addition lines may be directly used as an effective means to transfer genetic material from rye into bread wheat.  相似文献   

8.
Summary The meiotic pairing behaviour at metaphase I of a Triticum aestivum×Triticum monococcum hybrid has been studied by means of the C-banding technique to ascertain the homology between the chromosomes in the A genome of the two species. The technique allowed the A and B genome chromosomes and the 2D, 3D and 5D chromosomes to be identified. Differences in the level of chromosome pairing in the A genome were noted. The T. monococcum 4A chromosome did not pair with any of the T. aestivum chromosomes in any of the metaphase I cells analysed. Two reciprocal translocations between the 2B and 2D chromosomes on one side and the 2A and 3D on the other side have been identified. The usefulness of the C-banding technique in the study of chromosome homology among species related to wheat is discussed.  相似文献   

9.
Summary The Sr27 translocation in WRT238 was found to consist of chromosome arms 3RS of rye and 3AS of common wheat. An attempt was made to purposely produce compensating translocations having 3RS and a wheat homoeologous group 3L arm. To achieve this, plants, double monosomic for 3R and a wheat homoeologous group 3 chromosome, were irradiated (7.5 Gy gamma rays) or left untreated before being used to pollinate stem rust susceptible testers. Segregation for stem rust resistance was studied to identify F2 families with Sr27-carrying translocated chromosomes, these were confirmed by means of C-banding. Compensating translocations 3RS3AL and 3RS3BL) were obtained readily and at similar frequencies from untreated and irradiated plants (respectively, 7.2% and 9.3%). Both translocation types have impaired transmission and segregate approximately 3: 2 (present: absent) in the F2.  相似文献   

10.
G. Melz    R. Schlegel  J. Sybenga 《Plant Breeding》1988,100(3):169-172
The original identification of the chromosomes involved in each of the lines of the act of primary trisomics of winter rye variety ‘Esto’ does not correspond with recent results of gene localization studies. Using known morphological marker genes, N-banding and test crossing with the standard translocation tester set, a more precise identification was possible. In the nomenclature of the Triticinae, the lines can be designated as follows: A = 7R; B = 5R; C = 2R; D = 3R; E = 4R; F = 6R; G = 1R.  相似文献   

11.
A powdery mildew resistant double disomic wheat-rye substitution line carrying rye chromosomes 1R and 2R was crossed with normal bread wheats. The F2 generation was analysed cytologically by C-banding. Wheat-rye chromosome translocations involving both rye chromosomes 1R and 2R were frequent in F2. Lines with translocations of 1R and 2R were harvested separately. After four generations of selfing and selection for mildew resistance and fertility, fully fertile resistant lines were selected and analysed cytologically. Lines with 1BL/1RS and 2BS/2RL translocations were identified. The resistance on chromosome 1RS could not be shown to be different from control varieties carrying the same rye segment, while the resistance on 2RL is much broader than the earlier known 2RL derived resistance in the line Transec. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

12.
X. Q. Zhang    X. P. Wang    J.K. Jing    K. Ross    H. Hu    J. P. Gustafson   《Plant Breeding》1998,117(1):7-12
Five wheat-triticale doubled haploid (DH) lines— M08, V209, DH220-14-2, DH696-3-4 and M16 —derived from anther culture of F1s resulting from crosses involving hexaploid or octoploid triticale × hexaploid wheat, were characterized by cytological and biochemical markers. Cytological evidence from genomic in situ hybridization and C-banding indicated that DH lines M08 and V209 (2n= 42) each contained a pair of 1BL/1RS translocation chromosomes. DH220-14-2 (2n= 42) was also a translocated line with two pairs of chromosomes containing small fragments of rye. One of the translocation fragments carried the Sec-1R gene originating from the satellite region of 1RS; the origin of the other one remains unknown. DH696-3-4 (2n= 42) contained a 3D(3R) substitution. In M16 (2n= 44), three pairs of rye chromosomes, 3R, 4R and 6R, were present, 4R as an addition and 3D(3R) and 6D(6R) as substitutions. Biochemical, isozyme and storage protein markers confirmed the cytological conclusions. The advantages of transferring alien chromosomes or chromosome fragments into wheat and creating alien aneuploid lines by anther culture of hybrid F1s are discussed.  相似文献   

13.
Eight γ-irradiation-induced Triticum aestivumThinopyrum ponticum translocations conveying the blue aleurone were characterized using molecular cytogenetic approach. The size of alien chromosome segments was estimated by genomic in situ hybridization (GISH). The wheat chromosome segments involved in these translocations were clearly identified by two-color fluorescence in situ hybridization (FISH) with the probes of pAs1 and pSc119.2 (or pHvG38). Most of the detected translocations were reciprocal translocations involving wheat chromosomes 1B, 2D, 3A, 4A, 5B, 6B, 6D and 7A. This series of blue-grained wheat translocation lines would be useful in theoretical studies and wheat chromosome engineering breeding.  相似文献   

14.
In vitro culturing of plant cells can cause changes in karyotype. Chromosome variations following long-term propagation in suspension culture of Triticum timopheevii (Zhuk.) Zhuk. were studied by routine staining and C-banding. The culture was highly heterogeneous with respect to the number and structure of chromosomes. The modal class cells had a lower chromosome number than T. timopheevii (2n= 28). This data was confirmed by cytophotometric analysis of nuclear-DNA content. Frequencies of chromosome loss varied for different homoeologous groups. At genome chromosomes tended to be preferentially eliminated in cells of different ploidy levels. Deletions, insertions, translocations, telocentric chromosomes, isochromosomes and dicentrics and their derivatives were observed in cultured cells. Chromosomes of various homoeologous groups differed in the frequencies and spectra of re—arrangements, but most aberrations occurred in the G-genome chromosomes. In vitro chromosome modifications did not correspond to in vivo variation. Presumably, this difference was caused by differences in the mechanisms of adaptation to the environment at the levels of the cell and the whole organism. G-genome chromosomes were more frequently involved in this process, both in vivo and in vitro.  相似文献   

15.
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   

16.
Hordeum chilense is a wild barley species that has a high degree of genetic variability and significant potential for use in plant breeding. To establish a series of trisomics in H. chilense (2n = 14), plants with 2n + 1 chromosome numbers were isolated from the progenies of selfed triploid plants. Based on both fluorescent in situ hybridization with pAs1 and pTa71 repetitive DNA probes and C-banding patterns, seven different trisomics were tentatively identified. Primary trisomic plants were for chromosomes 1Hch, 4Hch, 5Hch, 6Hch and 7Hch. A secondary trisomic carrying a 5HchS-5HchS isochromosome as the extra chromosome and a trisomic for chromosome 3Hch heterozygous for the 3HchS-4HchL and 4HchS–3HchL interchange were identified. The trisomic for chromosome 1Hch cannot be phenotypically distinguished from the diploid. The rest of the trisomic types were distinguishable from the diploid by their morphological characteristics (relatively poor vigour, decreased size and shorter spikes) but they were morphologically indistinguishable from each other. The frequencies of trisomics among the progenies derived from self-fertilization of these aneuploids ranged from 10.7% to 37.5%, with an average frequency of 26.1%. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

17.
Summary By means of pachytene analysis 11 of the 12 possible types of primary trisomics of diploid S. tuberosum have been identified. The typical trivalent configurations for each chromosome are illustrated. Triplo-4,5,7 and 9 occurred more frequently whereas triplo-1 is still lacking in the series. Some of the features of trivalent associations at pachytene are discussed, as also the fact that in the present study only primary trisomics have been found.  相似文献   

18.
Shotgun survey sequences of flow‐sorted individual rye chromosomes were data mined for the presence of simple sequence repeats (SSRs). For 787,850 putative SSR loci, a total of 358,660 PCR primer pairs could be designed and 51,138 nonredundant SSR marker candidates were evaluated by in silico PCR. Of the 51,138 SSR primer candidates, 1,277 were associated with 1,125 rye gene models. A total of 2,112 of the potential SSR markers were randomly selected to represent about equal numbers for each of the rye chromosomes, and 856 SSRs were assigned to individual rye chromosomes experimentally. Potential transferability of rye SSRs to wheat and barley was of low efficiency with 4.3% (2,189) and 0.4% (223) of rye SSRs predicted to be amplified in wheat and barley, respectively. This data set of rye chromosome‐specific SSR markers will be useful for the specific detection of rye chromatin introgressed into wheat as well as for low‐cost genetic and physical mapping in rye without the need for high‐tech equipment.  相似文献   

19.
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   

20.
生物素标记的重复DNA序列与黑麦染色体的原位杂交   总被引:3,自引:0,他引:3  
钟少斌  张德玉 《作物学报》1995,21(6):691-694
本研究以两个黑麦重复DNA序列pSc119.1和pSc119.2作探针进行原位杂交,研究其在小麦和黑麦杂色体上的分布及在检测黑麦染色质中的应用。实验结果表明:pSc119.1分布于所有黑麦染色体的长短臂上,但在小麦染色体上几乎检测不到杂交信号,证明pSc119.1对黑麦染色体具有专化性。进一步用该探针与小麦品种“Amigo”的体细胞染色体进行原位杂交,可明显检测出其中一对含IRS的染色体。pSc1  相似文献   

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