Introgression of wheat chromosome 2D or 5D into tritordeum leads to free-threshing habit

Genome ◽  
2007 ◽  
Vol 50 (11) ◽  
pp. 994-1000 ◽  
Author(s):  
S. G. Atienza ◽  
A. C. Martín ◽  
A. Martín
Keyword(s):  
Mitotic Chromosome ◽  
Wheat Chromosome ◽  
Substitution Line ◽  
Hordeum Chilense ◽  
Chromosome Substitution ◽  
D Genome ◽  
Chromosome Substitution Line ◽  
New Crop ◽  
Free Threshing

Hexaploid tritordeum is the amphiploid derived from the cross between the diploid wild barley Hordeum chilense and durum wheat. The non-free-threshing habit is a constraint to this species becoming a new crop. Three tritordeum lines (HT374, HT376, and HT382) showing the free-threshing habit were selected from crosses between tritordeum and bread wheat. All three lines were euploids, as revealed by mitotic chromosome counting. Genomic in situ hybridization analysis made it possible to distinguish differences among these lines. While the line HT382 carries only 10 chromosomes from H. chilense, the lines HT374 and HT376 have 12. These results suggest that HT382 is a double chromosome substitution line between H. chilense and the wheat D genome, while HT374 and HT376 each have one pair of H. chilense (Hch) chromosomes substituted by wheat D chromosomes. Molecular characterization revealed that HT382 is a 1D/(1Hch), 2D/(2Hch) chromosome substitution line, whereas HT374 and HT376 have 5D/(5Hch) substitutions. On the basis of previous knowledge, it seems that the absence of chromosome 2Hch or 5Hch is more important for producing the free-threshing habit than the presence of chromosome 2D or 5D, while chromosome 1Hch seems to be unrelated to the trait. These free-threshing tritordeum lines constitute an important advance in the tritordeum breeding program.

Characterization of an Agropyron elongatum chromosome conferring resistance to cephalosporium stripe in common wheat

Genome ◽  
1996 ◽  
Vol 39 (1) ◽  
pp. 56-62 ◽  
Author(s):  
Xiwen Cai ◽  
Stephen S. Jones ◽  
Timothy D. Murray
Keyword(s):  
In Situ Hybridization ◽  
Wheat Chromosome ◽  
Triticum Aestivum L ◽  
Chromosome Substitution ◽  
Agropyron Elongatum ◽  
Breeding Lines ◽  
C Banding ◽  
Small Band ◽  
Cephalosporium Gramineum

Related wheat (Triticum aestivum L.) breeding lines, PI 561033, REA 9232, REA 9257, and CI 13113 were analyzed cytogenetically to characterize the association of resistance to cephalosporium stripe (caused by Cephalosporium gramineum Nis. & Ika.) with Agropyron elongatum chromatin. One pair of A. elongatum chromosomes was detected in PI 561033, REA 9232, and CI 13113 by genomic in situ hybridization. The sib line of PI 561033 and REA 9232, REA 9257, which is not resistant to this disease, lacked this pair of A. elongatum chromosomes. PI 561033 was characterized as a disomic T. aestivum – A. elongatum 6Ae#2(6A) chromosome substitution line using test crosses and C-banding. In situ hybridization and test crosses showed that the donor parent, CI 13113, also had chromosome 6A substituted by A. elongatum chromosome 6Ae#2. The C-banding pattern of 6Ae#2 showed two subterminal bands on the long arm and one small band proximal to the centromere on the short arm. Based on chromosome pairing and compensation, chromosome 6Ae#2 shows a close homoeologous relationship with wheat chromosome 6A. Key words : Cephalosporium gramineum, Agropyron elongatum, in situ hybridization, C-banding, chromosome substitution.

A chromosome of Hordeum chilense homoeologous to group 7 of wheat

1985 ◽  
Vol 27 (1) ◽  
pp. 101-104 ◽  
Author(s):  
T. E. Miller ◽  
S. M. Reader ◽  
C. C. Ainsworth
Keyword(s):  
Triticum Aestivum ◽  
Key Words ◽  
Isoelectric Focusing ◽  
Wheat Chromosome ◽  
Hordeum Chilense ◽  
Chromosome Substitution ◽  
Substitution Lines ◽  
Telocentric Chromosome ◽  
Chromosome Markers ◽  
Gel Isoelectric Focusing

Individual substitution lines have been produced with Hordeum chilense chromosome A substituted in turn for chromosome 7A, 7B, or 7D of Triticum aestivum. Telocentric substitutions with the α arm, substituted for chromosome 7A or 7D, or the β arm substituted for chromosome 7B have also been produced. The substitutions have been confirmed by the presence of a purple straw marker, by gel isoelectric focusing of α-amylase isozymes, and cytologically using telocentric chromosome markers. Chromosome A has consequently been designated 7Hch.Key words: Hordeum chilense, wheat, chromosome substitution, homoeology, α-amylase.

scholarly journals Molecular Cytogenetic Identification of a Novel Wheat–Thinopyrum ponticum 1JS (1B) Substitution Line Resistant to Powdery Mildew and Leaf Rust

2021 ◽  
Vol 12 ◽  
Author(s):  
Mingzhu Li ◽  
Yanzhen Wang ◽  
Xiaojuan Liu ◽  
Xingfeng Li ◽  
Honggang Wang ◽  
...  
Keyword(s):  
Powdery Mildew ◽  
Leaf Rust ◽  
Genetic Improvement ◽  
Wheat Chromosome ◽  
Substitution Line ◽  
Biotic And Abiotic Stresses ◽  
Thinopyrum Ponticum ◽  
Molecular Cytogenetic ◽  
Partial Amphiploid

Thinopyrum ponticum (2n = 10x = 70) is a wild relative of wheat with high tolerance to both biotic and abiotic stresses; it has been wildly used in wheat genetic improvement. A disomic substitution line named SN19647 was derived from a cross between Triticum aestivum and the wheat–Th. ponticum partial amphiploid SNTE20 (2n = 8x = 56). It was evaluated for disease resistance and characterized via sequential fluorescence in situ hybridization (FISH)-genomic in situ hybridization (GISH) and molecular markers. The results showed that SN19647 carried resistance to both powdery mildew and leaf rust. It contained 42 chromosomes with a pair of wheat chromosome 1B replaced by a pair of JS chromosomes from Th. ponticum. In addition to chromosomal substitution events, structural variation also occurred on wheat chromosomes 2A, 5A, 6B, and 7B. Based on marker analysis, 19 markers specific to the JS chromosome were obtained, of which seventeen markers belonged to homoeologous group one. These results indicated that SN19647 was a 1JS (1B) substitution line. Compared with the known 1JS (1D) substitution line CH10A5, it was found that 17 markers generated different specific bands to Th. ponticum, confirming the novelty of the 1JS chromosome in SN19647. Therefore, SN19647, resistant to powdery mildew and leaf rust, was a novel 1JS (1B) substitution line that can be used in wheat genetic improvement.

Comparative FISH mapping of two highly repetitive DNA sequences in Hordeum chilense (Roem. et Schult.)

Genome ◽  
2008 ◽  
Vol 51 (8) ◽  
pp. 580-588 ◽  
Author(s):  
S. Marín ◽  
A. Martín ◽  
F. Barro
Keyword(s):  
Repetitive Dna ◽  
Dna Sequences ◽  
Agronomic Traits ◽  
Hordeum Chilense ◽  
Chromosome 2 ◽  
Highly Repetitive Dna ◽  
Bridge Species ◽  
High Degree ◽  
New Crop

Hordeum chilense Roem. et Schult. (2n = 14) is an autogamous wild barley from Chile and Argentina included in the section Anisolepis Nevski. This species shows interesting agronomic traits that can be incorporated into crop plant species. Hordeum chilense has been successfully crossed with species of the genus Aegilops. Among the amphiploids obtained, the hexaploid tritordeum (2n = 6x = 42, AABBHchHch) is outstanding and shows good agronomic characteristics, suggesting its potential either as a new crop or as a bridge species to introgress interesting traits into cultivated cereals. The aim of the present work was to study the hybridization patterns of the two repetitive DNA probes pAs1 and pSc119.2 to evaluate their utility for the identification of H. chilense chromosomes. Fourteen lines of H. chilense were analyzed with fluorescent in situ hybridization using probes pSc119.2 and pAs1. The probe pAs1 was more widely dispersed than pSc119.2 over the H. chilense (Hch) genome. We found 89 different signals for pAs1, distributed evenly over the whole genome, and 10 for pSc119.2, located mainly over the telomeric regions. Five distinct hybridization signals were found for pAs1 and four distinct signals for pSc119.2. These signals allow the identification of different H. chilense lines. For example, centromeric signals for pAs1 on the short arms of chromosomes 1 and 7 identify line H46, and a telomeric signal for pSc119.2 on the short arm of chromosome 2 identifies line H1. A high degree of polymorphism in the hybridization patterns was found, confirming the extensive variability present in H. chilense. This work provides tools for the identification of H. chilense chromosomes in different genetic backgrounds.

IDENTITY OF THE WHEAT CHROMOSOMES REPLACED BY AGROPYRON CHROMOSOMES IN A TRIPLE ALIEN CHROMOSOME SUBSTITUTION LINE IMMUNE TO WHEAT STREAK MOSAIC

1970 ◽  
Vol 12 (1) ◽  
pp. 145-150 ◽  
Author(s):  
Ruby I. Larson ◽  
T. G. Atkinson
Keyword(s):  
Triticum Aestivum ◽  
Mosaic Virus ◽  
Growth Habit ◽  
Triticum Aestivum L ◽  
Wheat Streak Mosaic Virus ◽  
Substitution Line ◽  
Alien Chromosome ◽  
Chromosome Substitution ◽  
Agropyron Elongatum ◽  
Chromosome Substitution Line

A derivative of Triticum aestivum L. emend Thell. cultivar Rescue3 (2n = 42) × Agropyron elongatum (Host.) Beauv. (2n = 70) is immune to wheat streak mosaic virus Marmor virgatum McK., has 21 pairs of chromosomes, and hybridizes readily with wheat. By crossing with lines ditelosomic for known chromosomes it was determined that Agropyron chromosomes have replaced wheat chromosomes 4D, 5D, and 6D. In growth habit the immune line is like Rescue, but its long slender spikes, absence of awns, and small, slender, blue seeds resemble Agropyron.

scholarly journals Wheat, Rye, and Barley Genomes Can Associate during Meiosis in Newly Synthesized Trigeneric Hybrids

Plants ◽  
2021 ◽  
Vol 10 (1) ◽  
pp. 113
Author(s):  
María-Dolores Rey ◽  
Carmen Ramírez ◽  
Azahara C. Martín
Keyword(s):  
Chromosome Segregation ◽  
Genome Duplication ◽  
Triticum Turgidum ◽  
Aegilops Tauschii ◽  
Genomic In Situ Hybridization ◽  
Hordeum Chilense ◽  
Genomic Constitution ◽  
Chromosome Associations ◽  
High Level

Polyploidization, or whole genome duplication (WGD), has an important role in evolution and speciation. One of the biggest challenges faced by a new polyploid is meiosis, in particular, discriminating between multiple related chromosomes so that only homologs recombine to ensure regular chromosome segregation and fertility. Here, we report the production of two new hybrids formed by the genomes of species from three different genera: a hybrid between Aegilops tauschii (DD), Hordeum chilense (HchHch), and Secale cereale (RR) with the haploid genomic constitution HchDR (n = 7× = 21); and a hybrid between Triticum turgidum spp. durum (AABB), H. chilense, and S. cereale with the constitution ABHchR (n = 7× = 28). We used genomic in situ hybridization and immunolocalization of key meiotic proteins to establish the chromosome composition of the new hybrids and to study their meiotic behavior. Interestingly, there were multiple chromosome associations at metaphase I in both hybrids. A high level of crossover (CO) formation was observed in HchDR, which shows the possibility of meiotic recombination between the different genomes. We succeeded in the duplication of the ABHchR genome, and several amphiploids, AABBHchHchRR, were obtained and characterized. These results indicate that recombination between the genera of three economically important crops is possible.

Chromosomal organization of a sequence related to LTR-like elements of Ty1-copia retrotransposons in Avena species

Genome ◽  
1999 ◽  
Vol 42 (4) ◽  
pp. 706-713 ◽  
Author(s):  
Concha Linares ◽  
Antonio Serna ◽  
Araceli Fominaya
Keyword(s):  
In Situ Hybridization ◽  
Diploid Species ◽  
D Genome ◽  
Specific Sequence ◽  
Chromosomal Organization ◽  
Intergenomic Translocations ◽  
A Genome ◽  
Slot Blot Analysis ◽  
Copia Retrotransposons

A repetitive sequence, pAs17, was isolated from Avena strigosa (As genome) and characterized. The insert was 646 bp in length and showed 54% AT content. Databank searches revealed its high homology to the long terminal repeat (LTR) sequences of the specific family of Ty1-copia retrotransposons represented by WIS2-1A and Bare. It was also found to be 70% identical to the LTR domain of the WIS2-1A retroelement of wheat and 67% identical to the Bare-1 retroelement of barley. Southern hybridizations of pAs17 to diploid (A or C genomes), tetraploid (AC genomes), and hexaploid (ACD genomes) oat species revealed that it was absent in the C diploid species. Slot-blot analysis suggested that both diploid and tetraploid oat species contained 1.3 × 104 copies, indicating that they are a component of the A-genome chromosomes. The hexaploid species contained 2.4 × 104 copies, indicating that they are a component of both A- and D-genome chromosomes. This was confirmed by fluorescent in situ hybridization analyses using pAs17, two ribosomal sequences, and a C-genome specific sequence as probes. Further, the chromosomes involved in three C-A and three C-D intergenomic translocations in Avena murphyi (AC genomes) and Avena sativa cv. Extra Klock (ACD genomes), respectively, were identified. Based on its physical distribution and Southern hybridization patterns, a parental retrotransposon represented by pAs17 appears to have been active at least once during the evolution of the A genome in species of the Avena genus.Key words: chromosomal organization, in situ hybridization, intergenomic translocations, LTR sequence, oats.

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