Aneuploids of wheat and chromosomal localization of genes
Identification of useful major or minor genes is an important step in crop improvement programs. The chromosome location of such genes is critical for effective utilization and subsequent manipulation. Further, chromosomal localization will lead to the identification of genomic regions responsible for the expression of the trait of interest. DNA markers linked to these traits could be identified and used for marker-assisted breeding. Various cytogenetic stocks and techniques have been previously reported useful in localizing genes on wheat chromosomes. The objective of this paper is to assemble the most commonly used cytogenetic methods for the chromosomal localization of major genes in wheat including Chinese spring (CS) monosomics (Triticum aestivum, 2n=6x-1=41) and Langdon durum Dgenome disomic substitution lines (Triticum turgidum, 2n=4x-2+2=28). The paper reviewed and outlined the use and development of monomosic and substitution lines in a suitable genetic background for genetic analysis in wheat. The information may assist wheat researchers to locate and utilize newly identified genes in breeding programs.
Key words: Aneuploids, Chinese spring, chromosome, cytogenetics, Langdon durum, monosomics, substitution lines.