Abstract: Cytological studies were conducted on pollen mother cells (PMCs) meiosis of autotetraploid broccoli using chromosome p reparation technique. Results showed that the PMCs meiosis of the autotetrap loid was similar to the diploid. However, there were particularities: in metaphase, multivalent, quadrivalent, trivalent, bivalent and univalentwere observed. Some of the chromosomeswere found not to rank atmetaphase plate in metaphaseⅠand metaphaseⅡcells. In anaphaseⅠand anaphaseⅡ, there were lagged chromosomes, chromosome bridges and fragments. During anaphaseⅡand telophaseⅡchromosome segregationswere not synchronous and equal. At tetrad stage, dyad, triad, tetrad withmicronucleus and polyad appeared. The emergence frequency of abnormal phenomena in each stage ofmeiosiswas counted and itwas 31.5% in autotetrap loid. Abnormal meiosis of PMCswas the cytogenetic reason for fertility reduction of autotetrap loid broccoli pollen.

Key words: Broccoli, Autotetrap loid, PMCs, Meiosis