Microsporocyte meiosis and male gametophyte abortion of spring radish male-sterile line 4-05A.

The spring radish(Raphanus sativus L.)male-sterile line 4-05A and its maintainer line 4-05B were studied by morphological and cytological methods.The anthers of A line were empty without pollen and were smaller than those of B line.The corollas of A line were smaller but the pistils are longer.Microsporocyte meiosis and male gametophyte development are observed using pollen preparation techniques.The male-sterile line 4-05A can be categorized to pollen abortion type based on our observation.The microsporocyte meiosis was normal and monocyte pollen was observed.However the male gametophytes developed abnormally and ceased at late mononuclear stage,consequently,no normal pollen grains were produced.The cytoplast division of meiosis was the simultaneous type.