chromosome pairing and heterozygote translocation in oltan cotton cultivar and its crossing progenies

a cytogenetic study was performed on 11 tetraploid cotton cultivars (gossypium hirsutum l.)including the oltan cultivar and its crossing progenies. the chromosome pairing and chiasma frequency, aswell as meiotic abnormalities were compared among the genotypes studied. heterozygote translocations withalternate orientation were observed between some of the chromosomes of the a genome and those of dgenome in some of the cultivars, which may bring about new genetic rearrangement to be used in breedingprograms. meiotic abnormalities including formation of laggard chromosome, stickiness, as well asdisorganized chromosomes occurred in some of the cultivars, which may cause pollen sterility. bchromosomeswere observed in some of the cultivars. the cultivars studied differed significantly in theircytogenetic characteristics, partly indicating their genomic differences, which may be used in cotton breeding.