A STUDY OF GENOME STRUCTURE OF WHEAT-AGRO PYRON ON DISOMIC ADDITION LINES (2N=44)

Karyotypes of four wheat-Agropyron disomic addition lines (DAL) were s tudied using banding techniques and analysis of meiotic chromosome con jugation. The examined DAL forms carry 44 chromosomes and, as the anal ysis of DAL139 and DAL828 populations showed, are quite constant cytol ogically. DAL karyotypes were shown to be wheat chromosomes (genomes A , B, and D) and one Agropyron chromosome. According to the C-segmentat ion pattern, the wheat chromosomes are completely indentical to the st arting wheat forms. The - additional Agropyron chromosomes in DAL828 a nd DAL139 karyotypes are not identical. The presence of - additional A gropyron chromosomes iii DAL is confirmed by analysis of the meiotic c hromosome conjugation in the Fl hybrids obtained by crossing DAL with Mironovskaya 808 and the starting parental forms of incomplete wheat-A gropyron amphidiploids (IWAA) (2n = 56). The univalents corresponding to alien additional chromosomes always are found in such hybrid forms at metaphase I (MI) of meiosis.