Attempts to induce homoeologous pairing between wheat and Agropyron cristatum genomes

Agropyron cristatum (2n = 4x = 28, PPPP) possesses potentially valuable traits that could be used in wheat (Triticum aestivum) improvement through interspecific hybridization. Homoeologous pairing between wheat chromosomes and P chromosomes added to wheat in a set of wheat – A. cristatum addition lines was assessed. First, the Ph-suppressing effect of P chromosomes (except 7P) was analyzed. It was concluded that this system is polygenic with no major gene, and consequently, has no prospect in the transfer of alien genes from wild relatives. In a second step, the potential of the deletion ph1b of the Ph1 gene for inducing P–ABD pairing was evaluated. Allosyndetic associations between P and ABD genomes are very rare. This very low level of pairing is likely due to divergence in the repeated sequences between Agropyron and wheat genomes. Development of translocation lines using ionizing radiation seems to be a more suitable technique than homoeologous recombination to exploit the A. cristatum genome in wheat improvement.Key words: Triticum aestivum, Agropyron cristatum, addition line, GISH, Ph1 gene.

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An interspecific hybrid and amphiploid produced from Triticum aestivum crosses with Agropyron cristatum and Agropyron desertorum

Genome ◽

10.1139/g90-085 ◽

1990 ◽

Vol 33 (4) ◽

pp. 581-584 ◽

Cited By ~ 39

Author(s):

A. E. Limin ◽

D. B. Fowler

Keyword(s):

Triticum Aestivum ◽

Interspecific Hybrid ◽

Intergeneric Hybrid ◽

Colchicine Treatment ◽

Triticum Aestivum L ◽

Agropyron Cristatum ◽

Homoeologous Pairing ◽

Agropyron Desertorum ◽

Hybrid Plants ◽

Homoeologous Relationships

Agropyron cristatum L. Gaertner (2n = 14) and Agropyron desertorum (Fisch. ex Link) Schultes (2n = 28) cultivars were crossed with common wheat (Triticum aestivum L. em. Thell. 2n = 42, ABD genomes) in an attempt to bring the P genome of Agropyron into a wheat background for future genetic exploitation and to evaluate possible homoeology with the wheat genomes. Interspecific hybrid plants were obtained from crosses using both Agropyron species. Chromosome doubled amphiploids (2n = 56, AABBDDPP) were successfully produced by colchicine treatment of hybrid plants from the T. aestivum – A. cristatum cross. Meiotic cells of the amphiploid contained the expected 28 chromosome pairs but also exhibited a considerable amount of chromosome pairing disturbance, resulting in an average of 3.55 univalents per cell. Consequently, fertility was reduced in the amphiploid and the progeny were frequently aneuploid. Homoeologous pairing in the T. aestivum – A. cristatum hybrid was low, but the pairing disruption exhibited in the amphiploid suggested that homoeologous relationships may have been masked in the hybrid.Key words: Triticum aestivum, Agropyron cristatum, chiasma frequency, intergeneric hybrid, amphiploid.

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Molecular diversity analysis in hexaploid wheat (Triticum aestivum L.) and two Aegilops species (Aegilops crassa and Aegilops cylindrica) using CBDP and SCoT markers

Journal of Genetic Engineering and Biotechnology ◽

10.1186/s43141-021-00157-8 ◽

2021 ◽

Vol 19 (1) ◽

Author(s):

Ghazal Ghobadi ◽

Alireza Etminan ◽

Ali Mehras Mehrabi ◽

Lia Shooshtari

Keyword(s):

Genetic Diversity ◽

Triticum Aestivum ◽

Gene Diversity ◽

Polymorphic Information Content ◽

Crop Improvement ◽

Wild Relatives ◽

Resolving Power ◽

Start Codon ◽

Aegilops Cylindrica ◽

Aegilops Crassa

Abstract Background Evaluation of genetic diversity and relationships among crop wild relatives is an important task in crop improvement. The main objective of the current study was to estimate molecular variability within the set of 91 samples from Triticum aestivum, Aegilops cylindrica, and Aegilops crassa species using 30 CAAT box–derived polymorphism (CBDP) and start codon targeted (SCoT) markers. Results Fifteen SCoT and Fifteen CBDP primers produced 262 and 298 fragments which all of them were polymorphic, respectively. The number of polymorphic bands (NPB), polymorphic information content (PIC), resolving power (Rp), and marker index (MI) for SCoT primers ranged from 14 to 23, 0.31 to 0.39, 2.55 to 7.49, and 7.56 to 14.46 with an average of 17.47, 0.34, 10.44, and 5.69, respectively, whereas these values for CBDP primers were 15 to 26, 0.28 to 0.36, 3.82 to 6.94, and 4.74 to 7.96 with a mean of 19.87, 0.31, 5.35, and 6.24, respectively. Based on both marker systems, analysis of molecular variance (AMOVA) indicated that the portion of genetic diversity within species was more than among them. In both analyses, the highest values of the number of observed (Na) and effective alleles (Ne), Nei’s gene diversity (He), and Shannon’s information index (I) were estimated for Ae. cylindrica species. Conclusion The results of cluster analysis and population structure showed that SCoT and CBDP markers grouped all samples based on their genomic constitutions. In conclusion, the used markers are very effective techniques for the evaluation of the genetic diversity in wild relatives of wheat.

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Characterization of interspecific hybrids of Triticum aestivum x Aegilops sp. without 5B chromosome for induced homoeologous pairing

Journal of Plant Biochemistry and Biotechnology ◽

10.1007/s13562-015-0307-9 ◽

2015 ◽

Vol 25 (1) ◽

pp. 117-120 ◽

Cited By ~ 7

Author(s):

Imran Sheikh ◽

Prachi Sharma ◽

Shailender Kumar Verma ◽

Satish Kumar ◽

Sachin Malik ◽

...

Keyword(s):

Triticum Aestivum ◽

Interspecific Hybrids ◽

Homoeologous Pairing ◽

Induced Homoeologous Pairing

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Molecular characterization and mapping of ALMT1, the aluminium-tolerance gene of bread wheat (Triticum aestivum L.)

Genome ◽

10.1139/g05-054 ◽

2005 ◽

Vol 48 (5) ◽

pp. 781-791 ◽

Cited By ~ 119

Author(s):

Harsh Raman ◽

Kerong Zhang ◽

Mehmet Cakir ◽

Rudi Appels ◽

David F Garvin ◽

...

Keyword(s):

Triticum Aestivum ◽

Genomic Structure ◽

Major Gene ◽

Aluminium Tolerance ◽

Deletion Mapping ◽

Al Tolerance ◽

Diverse Range ◽

Wheat Genotypes ◽

Almt1 Gene ◽

Tolerance Gene

The major aluminum (Al) tolerance gene in wheat ALMT1 confers. An Al-activated efflux of malate from root apices. We determined the genomic structure of the ALMT1 gene and found it consists of 6 exons interrupted by 5 introns. Sequencing a range of wheat genotypes identified 3 alleles for ALMT1, 1 of which was identical to the ALMT1 gene from an Aegilops tauschii accession. The ALMT1 gene was mapped to chromosome 4DL using 'Chinese Spring' deletion lines, and loss of ALMT1 coincided with the loss of both Al tolerance and Al-activated malate efflux. Aluminium tolerance in each of 5 different doubled-haploid populations was found to be conditioned by a single major gene. When ALMT1 was polymorphic between the parental lines, QTL and linkage analyses indicated that ALMT1 mapped to chromosome 4DL and cosegregated with Al tolerance. In 2 populations examined, Al tolerance also segregated with a greater capacity for Al-activated malate efflux. Aluminium tolerance was not associated with a particular coding allele for ALMT1, but was significantly correlated with the relative level of ALMT1 expression. These findings suggest that the Al tolerance in a diverse range of wheat genotypes is primarily conditioned by ALMT1.Key words: aluminum, tolerance, genetic marker, Triticum aestivum, QTL, deletion mapping.

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