小白菜小孢子发育与花器官形态相关性

通过DAPI染色观察不同大小的小白菜花蕾内小孢子发育外部形态结构特征及细胞学特征变化，以确定花粉发育时期，找出小孢子发育时期和花外部形态结构相关性，为花药或小孢子培养提供细胞学证据。研究结果表明：小白菜小孢子发育经过二分体时期、四分体时期、单核靠边期、单核居中期、2-胞花粉和3-胞花粉时期，各时期特征明显；且各发育时期与花蕾及花药外部形态密切相关，其中单核靠边期时花蕾纵径为 2.68~3.80 mm，横径为1.91~2.19 mm，花药纵径为 1.76~2.39 mm，横径为 0.64~0.82 mm，花药颜色为浅黄绿色，此时期适合花药、小孢子培养；因此可根据小白菜花蕾形态、大小和小孢子发育时期的相关性，确定花药、小孢子培养最佳时期的选蕾标准。

Correlation Analysis of Microspore Development and Floral Organ Morphology in Brassica chinensis L.

Full flower buds with different lengths were collected and DAPI staining method was used in cytological observation of Brassica chinensis L. microspore development for confirming the pollen development periods after morphological observation, the cytology characteristics of Brassica chinensis L. microspore and morphology of flower in organs of different development periods organ were used to determine the relationship between microspore development and buds morphology, which would provide evidence for culture of anther and microspore. The results showed that the microspore development had obvious characteritics at the stage of microspore mother cell, tetrad, early or mid-uninucleate, late uninucleate, bicellular pollen and tricellular pollen periods obviously. The microspore development had correlativity with the morphological characteristics of the buds and anthers. Among them, when the most microspores were in the period of late uninucleate, the buds were 2.68-3.8 mm in height and 1.91-2.19 mm in diameter, the anthers were 1.76-2.39 mm in height and 0.64-0.82 mm in diameter, the anthers showed light yellow green. Therefore, we can make clear the development period of Brassica chinensis L. microspore by morphological characteristics of flower organs, and determine the criterion for bud selection in optimal period of anthers culture.