Abnormal mitosis induced by wheat-rye 1R monosomic addition lines.

Area of Science:

• Plant genetics
• Cytogenetics
• Molecular biology

Background:

• Triticale, a hybrid of wheat and rye, offers potential for crop improvement.
• Understanding chromosome behavior in wheat-rye hybrids is crucial for breeding programs.

Purpose of the Study:

• To investigate the mitotic chromosome behavior in wheat-rye addition and translocation lines.
• To identify genetic variations and chromosomal abnormalities in triticale progeny.

Main Methods:

• Octoploid triticale development from Triticum aestivum and Secale cereale.
• In situ hybridization using rye genomic DNA and specific repetitive sequences (pAs1, pSc119.2).
• Analysis of mitotic chromosomes in triticale progeny, including monosomic addition and translocation lines.

Main Results:

• Identified three wheat-rye 1R monosomic addition lines and one line with a 1BL.1RS translocation.
• Observed abnormal mitosis in 1R monosomic addition lines, including lagging chromosomes, micronuclei, and chromosomal bridges.
• Detected abnormal mitotic behavior and genetic variations (e.g., chromosome loss) in self-progeny carrying the 1R chromosome or its arm.

Conclusions:

• A single added 1R chromosome can induce abnormal mitotic behavior in both wheat and rye chromosomes.
• Sibling 1R monosomic addition lines can exhibit different genetic variations, suggesting complex interactions.
• The presence of the 1R chromosome can lead to significant chromosomal instability and genetic alterations in wheat-rye hybrids.