Abstract:

The cytological characteristics of microspores in Chinese flowering cabbage at different developmental periods were studied to reveal the relationship between microspore development and buds morphology, which would provide evidences for the culturing of anthers and microspores. The results showed that the microspore developed in tetrad, early- or mid-uninucleate, late-uninucleate and binucleate stages obviously. The microspore development showed correlativity with the morphological characteristics of buds and anthers. The buds 3.05-3.39 mm in height, the calyx 3.25-3.46 mm in length, the petal 2.10-2.33 mm in length, the ratio of flap to calyx 0.63-0.71, the anther 2.57-2.89 mm in length, and the ratio of flap 0.77-0.85 were discovered to contain microspores at the late uninucleate. These were suitable for the identification of optimal sampling period of flower buds in different materials. At the late uninucleate stage, it was necessary that the anthers should be covered by the sepal, the anthers slightly longer than petals, and the flower bud was full, the petals and anthers showed pale yellow. Therefore, we can judge the development stage of Chinese flowering cabbage microspore by morphological characteristics of flower organs so as to define the standard of bud selection in correspondence with the optimal stage of anthers culture.

Key words: Chinese flowering cabbage, microspore, developmental period, flowers organs, morphological characteristics