关键词: 枣, 减数分裂, 二分体, 三分体, 多分体, 胞质分裂

Abstract:

The natural triploid Chinese jujube‘Zanhuang Dazao’（2n = 3x = 36）and artificial autotetraploid ‘Chenguang’（2n = 4x = 48）were used to study the chromosome behaviors，especially abnormal meiosis，of pollen mother cells（PMCs）. Conventional pressed slice method was used to observe the meiosis of PMCs under Olympus light microscope. Abnormal phenomenon was observed in each stage of meiosis. Univalents，bivalents，trivalents and quadrivalents appeared while two nucleoli were observed at diakinesis in both‘Zanhuang Dazao’and‘Chenguang’. Some chromosomes were found not being arranged at metaphase plate at metaphaseⅠand metaphaseⅡfollowed by lagged chromosomes and chromosome bridges appeared at anaphaseⅠand anaphaseⅡ. Parallel and tripolar spindles were observed besides normal perpendicular spindles at metaphase Ⅱ. Dyads，triads and tetrads with or without micronucleus appeared at tetrad stage. Polyads were only observed in‘Zanhuang Dazao’at tetrad stage and abnoraml cytokinesis at anaphaseⅠand Ⅱ were only detected in‘Chenguang’. Abnormal meiosis behavior led to gamete diversity，pollen deformity and low pollen fertility in polyploid Chinese jujube.‘Zanhuang Dazao’was preliminarily inferred to be an autopolyploid，and its meiosis behavior is more abnormal than those of autotetraploid‘Chenguang’.

Key words: Chinese jujube, meiosis；dyad, triad, polyad, cytokinesis