白菜核雄性不育系可育和不育花药中Ca2+的分布

研究了白菜(Brassica campestris L. ssp.chinensis Makino)细胞核雄性不育系花药中Ca2 的分布特征.在可育花药发育过程中,减数分裂后花药壁细胞中钙颗粒明显增加.早期小孢子开始积累钙颗粒并特异性地附在小液泡膜上.小孢子分裂后,大液泡消失过程中又伴随着许多钙颗粒附在小液泡膜上,显示出Ca2 与花粉中液泡的形成和分解有关.在不育花药中,最早出现的钙颗粒异常分布是在小孢子母细胞的胼胝质壁中积累了较多的钙颗粒.然而,在小孢子细胞质中钙颗粒一直很少,也不形成大液泡,最后通过细胞质收缩的方式败育.这是首次发现Ca2 参与调控花药发育过程,其异常分布与花粉败育密切相关.

Calcium Distribution in Fertile and Sterile Anthers of a Genic Male Sterile Chinese Cabbage

Potassium antimonite was used to lo- cate calcium in the fertile and sterile anthers of a genic male sterile Chinese cabbage (Brassica campestris L. ssp. chinensis Makino) to probe the relation between Ca2+ and fertility and steril- ity of anthers of the cabbage. During fertile an- ther development, calcium granules increase in number in anther wall cells after meiosis, and then appeared also in locule, suggesting a cal- cium influx into locule from anther wall cells (Plate I-4). Then the number of calcium gran- ules in microspore cytoplasm also increased at early stage (Plate II-1), accumulated mainly on the membrane of small vacuoles which were fus- ing to form big ones to make a polarity in the cell and to prepare asymmetric division of mi- crospore (Plate II-3, 4). After microspore divi- sion and the big vacuole decomposition, many calcium granules accumulated again on the mem- brane of the vacuoles (Plate III-1, 2), displaying calcium regulates vacuole formation and decom-position during pollen development. In sterile anthers, abnormal distribution of calcium gran- ules first appeared in callus wall of microspore mother cell (Plate IV-1). However, only a few calcium granules appeared in early microspores, which then could not form small vacuoles and finally a big vacuole (Plate IV-2, 3). The abort- ing microspores degenerate by cytoplasm shrink- ing (Plate IV-5, 6). The difference pattern of dis- tribution of calcium granules between the fertile and sterile anthers indicates that anomalies in the distribution of calcium accumulation are cor- related with the failure of pollen development and pollen abortion.