Stable minichromosome and functional neocentromere derived from rye 7R chromosome arm.

Background: The study of newly formed centromere with stable transmission ability can provide theoretical guidance for the construction of artificial chromosomes. More neocentromeres are needed to study the mechanisms of their formation.

Results: In this study, a minichromosome 7RLmini was derived from the progeny of wheat-rye 7R monosomic addition line.

Unveiling the distinctive traits of functional rye centromeres: minisatellites, retrotransposons, and R-loop formation.

Centromeres play a vital role in cellular division by facilitating kinetochore assembly and spindle attachments. Despite their conserved functionality, centromeric DNA sequences exhibit rapid evolution, presenting diverse sizes and compositions across species. The functional significance of rye centromeric DNA sequences, particularly in centromere identity, remains unclear.

Identification and validation of major and stable quantitative trait locus for falling number in common wheat (Triticum aestivum L.).

A major and stable QTL, QFn.sau-1B.2, which can explain 13.

The different subtelomeric structure among 1RS arms in wheat-rye 1BL.1RS translocations affecting their meiotic recombination and inducing their structural variation.

Background: The 1RS arm of wheat-rye 1BL.1RS translocations contains several subtelomeric tandem repeat families. To study the effect of the difference in the composition of these tandem repeats on the meiotic recombination of 1RS arms can help to enrich the genetic diversity of 1BL.

Systemic development of wheat-Thinopyrum elongatum translocation lines and their deployment in wheat breeding for Fusarium head blight resistance.

Fusarium head blight (FHB), mainly caused by Fusarium graminearum, is one of the most destructive diseases of wheat (Triticum aestivum) around the world. FHB causes significant yield losses and reduces grain quality. The lack of resistance resources is a major bottleneck for wheat FHB resistance breeding.

Development and cytological characterization of wheat- translocation lines with novel stripe rust resistance gene.

Wheat stripe rust is a destructive disease in many cool and temperate regions around the world. Exploiting novel sources of resistance can provide wheat cultivars with robust and durable resistance to stripe rust. The wheat- addition line TAI-14 was proven to carry a stripe rust resistance gene (named as ) on the alien chromosome.

Physical mapping of a new powdery mildew resistance locus from chromosome 4AgS.

(Podp.) Barkworth and D.R.

Location of Tandem Repeats on Wheat Chromosome 5B and the Breakpoint on the 5BS Arm in Wheat Translocation T7BS.7BL-5BS Using Single-Copy FISH Analysis.

Wheat ( L.) is rich in tandem repeats, and this is helpful in studying its karyotypic evolution. Some tandem repeats have not been assembled into the wheat genome sequence.

Variations of wheat ( L.) chromosomes caused by the 5A chromosomes with complex cytological structure.

To study the effects of structural alterations of chromosomes caused by tandem repeats on the meiotic recombination, the wheat ( L.) 5A chromosomes with different structure from ten wheat cultivars were used to investigate their meiotic recombination using non-denaturing fluorescence hybridization (ND-FISH) technology. Fifteen cross combinations were carried out and they were divided into seven F categories.

Centromere-Specific Single-Copy Sequences of Species.

Single-copy FISH analysis is a useful tool to physically locate a given sequence on chromosome. Centromeric single-copy sequences can be used to locate the position of centromere and disclose the subtle differences among different centromeres. Nine centromeric single-copy sequences 1R1, 3R1, 4R1, 4R2, 5R1, 5R2, 6R2, 6R3, and 7R1 were cloned from Kustro ( L.

Establishment and identification of six wheat-Thinopyrum ponticum disomic addition lines derived from partial amphiploid Xiaoyan 7430.

Six wheat-Thinopyrum ponticum disomic addition lines derived from partial amphiploid Xiaoyan 7430 were identified using in situ hybridization and SNP microarray, the homoeologous group and stripe rust resistance of each alien chromosome were determined, and Th. ponticum chromosome-specific markers were developed. Xiaoyan 7430 is a significant partial amphiploid, which is used to set up a bridge for transferring valuable genes from Thinopyrum ponticum (Podp.

The Physical Location of Stripe Rust Resistance Genes on Chromosome 6 of Rye ( L.) AR106BONE.

It was reported that the chromosome 6R of rye ( L.) carries stripe rust resistance gene , and the region with the candidate resistance gene(s) still needs to be narrowed down. This study confirmed that the chromosome 6RL derived from rye AR106BONE contains stripe rust resistance gene(s).

Establishment of a set of wheat-rye addition lines with resistance to stem rust.

Complete new wheat-rye disomic, telosomic addition lines and various chromosomal aberrations were developed and characterized by molecular cytogenetic method as novel chromosome engineering materials. A new stem rust resistance (Ug99) gene was located on 3RL. Wheat stem rust, caused by Puccinia graminis f.

Variations of subtelomeric tandem repeats and rDNA on chromosome 1RS arms in the genus Secale and 1BL.1RS translocations.

Background: The wheat-rye 1BL.1RS translocations have played an important role in common wheat breeding programs. Subtelomeric tandem repeats have been often used to investigate polymorphisms of 1RS arms, but further research about their organizations on the 1RS chromosome is needed.

FISH landmarks reflecting meiotic recombination and structural alterations of chromosomes in wheat (Triticum aestivum L.).

Background: DNA sequence composition affects meiotic recombination. However, the correlation between tandem repeat composition and meiotic recombination in common wheat (Triticum aestivum L.) is unclear.

Molecular and Cytogenetic Characterization of a Wheat-Rye 7BS.7RL Translocation Line with Resistance to Stripe Rust, Powdery Mildew, and Fusarium Head Blight.

is used as a source of genes for disease resistance in wheat cultivation. In this study, a homozygous translocation line (RT14-245) that originated from a cross between a commercial wheat cultivar (Mianyang 11) and a local Chinese variety of rye (Baili was developed. Multicolor fluorescence in situ hybridization and PCR analysis demonstrated that the translocation chromosome was 7BS.

Molecular dissection of Secale africanum chromosome 6R in wheat enabled localization of genes for resistance to powdery mildew and stripe rust.

Background: Introgression of chromatin from Secale species into common wheat has for decades been a successful strategy for controlling the wheat diseases. The wild Secale species, Secale africanum Stapf., is a valuable source for resistance to foliar disease of wheat.

New ND-FISH-Positive Oligo Probes for Identifying Chromosomes in Wheat Backgrounds.

has been widely used to improve wheat ( L.) cultivars. Non-denaturing fluorescence in situ hybridization (ND-FISH) technology using oligonucleotides (oligo) as probes provides a convenient and efficient way to identify alien chromosomes in wheat backgrounds.

The Polymorphisms of Oligonucleotide Probes in Wheat Cultivars Determined by ND-FISH.

Non-denaturing fluorescence in situ hybridization (ND-FISH) has been used to distinguish wheat chromosomes and to detect alien chromosomes in the wheat genome. In this study, five different oligonucleotide probes were used with ND-FISH to examine 21 wheat cultivars and lines. These oligonucleotide probes distinguished 42 wheat chromosomes and also detected rye chromatin in the wheat genome.

Using the 6RL Minichromosome of Rye ( L.) to Create Wheat-Rye 6D/6RL Small Segment Translocation Lines with Powdery Mildew Resistance.

Long arms of rye ( L.) chromosome 6 (6RL) carry powdery mildew resistance genes. However, these sources of resistance have not yet been successfully used in commercial wheat cultivars.

Development and molecular cytogenetic identification of a new wheat-rye 4R chromosome disomic addition line with resistances to powdery mildew, stripe rust and sharp eyespot.

A wheat-rye 4R chromosome disomic addition line with resistances to powdery mildew, stripe rust, sharp eyespot and high kernel number per spike was developed and characterized by molecular cytogenetic method as novel resistant germplasm. Rye (Secale cereale L.), a close relative of common wheat, is an important and valuable gene donor with multiple disease resistance for wheat improvement.

Physical location of tandem repeats in the wheat genome and application for chromosome identification.

A general distribution of tandem repeats (TRs) in the wheat genome was predicted and a new web page combined with fluorescence in situ hybridization experiments, and the newly developed Oligo probes will improve the resolution for wheat chromosome identification. Comprehensive sequence analysis of tandem repeats (TR) in the wheat reference genome permits discovery and application of TRs for chromosome identification. Genome-wide localization of TRs was identified in the reference sequences of Chinese Spring using Tandem Repeat Finder (TRF).

Developing New Oligo Probes to Distinguish Specific Chromosomal Segments and the A, B, D Genomes of Wheat ( L.) Using ND-FISH.

Non-denaturing FISH (ND-FISH) technology has been widely used to study the chromosomes of Triticeae species because of its convenience. The oligo probes for ND-FISH analysis of wheat ( L.) chromosomes are still limited.

Utilization of a Wheat55K SNP Array for Mapping of Major QTL for Temporal Expression of the Tiller Number.

Maximum tiller number and productive tiller number are important traits for wheat grain yield, but research involving the temporal expression of tiller number at different quantitative trait loci (QTL) levels is limited. In the present study, a population set of 371 recombined inbred lines derived from a cross between Chuan-Nong18 and T1208 was used to construct a high-density genetic map using a Wheat55K SNP Array and to perform dynamic QTL analysis of the tiller number at four growth stages. A high-density genetic map containing 11,583 SNP markers and 59 SSR markers that spanned 4,513.

Oligonucleotides and ND-FISH Displaying Different Arrangements of Tandem Repeats and Identification of Dasypyrum villosum Chromosomes in Wheat Backgrounds.

Oligonucleotide probes and the non-denaturing fluorescence in situ hybridization (ND-FISH) technique are widely used to analyze plant chromosomes because they are convenient tools. New oligonucleotide probes, Oligo-Ku, Oligo-3B117.1, Oligo-3B117.