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用焦锑酸盐沉淀法对甘蓝型油菜（ＢｒａｓｉｃａｎａｐｕｓＬ．）授粉前后珠孔和胚囊中的钙进行了超微细胞化学定位。Ｘ射线能谱微区定性分析（ＥＤＸＡ）表明前法所得沉淀确系焦锑酸钙。同时利用图像处理系统对胚囊成员细胞中钙沉淀颗粒的体密度和大小进行了定量分析。结果显示，授粉前后内、外珠孔处钙沉淀明显较珠被其它部位为多，钙主要分布在细胞壁和胞间基质等质外体系统中。授粉前２个助细胞中均含有较其它细胞为多的钙沉淀，约为卵细胞的２５倍，中央细胞的１９倍；但沉淀颗粒的直径仅为它们的２／３左右。助细胞中含钙最多的部位是丝状器和细胞核。授粉后１对姊妹助细胞均明显退化，钙含量显著增高，约为授粉前的２４倍；钙颗粒明显减小，不足授粉前的１／３。讨论了钙的分布与助细胞的退化及其功能的关系。
Calcium in beads and embryo sacs before and after pollination of Brassica napus L. was ultra-cytochemically localized with pyroantimonate precipitation. X-ray energy spectrum microanalysis (EDXA) shows that the precipitation obtained by the former method is indeed calcium pyroantimonate. At the same time, the image processing system was used to quantitatively analyze the body density and size of calcium precipitates in the embryo sac member cells. The results showed that the calcium deposition in the outer and inner beads was significantly more than that in other parts of the bead before and after pollination. Calcium was mainly distributed in the apoplast system such as the cell wall and the intercellular matrix. Before the pollination, both of the two helper cells contained more calcium deposits than other cells, about 2.5 times that of the egg cells and 1.9 times that of the central cells. However, the diameters of the precipitated particles were only about 2/3 of them. The most abundant sites in helper cells are the filamentous organs and the nucleus. After pollination, one pair of sister helper cells were significantly degraded, calcium content was significantly increased, about 2 4 times before pollination; calcium particles significantly reduced, less than 1/3 before pollination. The relationship between the distribution of calcium and the cell degeneration and its function is discussed.