萝卜花粉母细胞减数分裂及其雄配子体发育

Pollen mother cell mitosis and male gametophyte development of Raphanus sativus L.

采用染色体压片法和爱氏苏木精染色一冬青油透明法研究了萝卜花粉母细胞减数分裂及其雄配子体发育过程。结果表明：萝卜花粉母细胞减数分裂的胞质分裂方式为同时型，终变期二价体多为棒状和环状，有3％的异型二价体，中期Ⅰ出现少量染色体落后现象，中期Ⅱ纺锤体的排列方式有垂直型、平行型和八字型，四分体排列按比例依次为十字交叉型、四面体型和左右对称型。成熟花粉为3核型，包括1个营养核及2个精核，具3个萌发孔。2．0-4．5mm的花蕾处于单核期，可作为花药培养或小孢子培养的选材依据。花粉可染率为87．9％，败育多发生在单核期。

Chromosomal meiotic behaviors and male gametophytes development of Raphanus sativus L. were studied using chromosome preparation and Ehrlich＇s hematoxylin staining-methyl salicylate clearing technique. The results were as follows： the meiosis in pollen mother cells of radish simultaneous cytokinesis and chromosomes could be identified as rod or ring bivalents in diakinesis except for 3% abnormal. A few lagging chromosomes appeared in metaphases I and the spindle arranged in vertical, parallel and the 八 like in metaphase Ⅱ. The microspores in tetrad stage showed the arrangement of decussate type, tetrahedral type and isobilateral type. The mature pollen grains contained three apertures and three nucleus which were made up of two pronucleus and one alimentation nucleus. The buds larged from 2.0 to 4. 5 mm were usually at uninucleate stage which were adapt for microspore culture. About 87.9% of pollens were activated with the rest aborted at uninucleate stage.