The analysis of the biological characters in hexapod hybrids derived from Brassica carinata and Brassica campestris

Chinese. 通过杂交和染色体加倍人工合成了埃塞俄比亚芥×白菜型油菜间的三倍体和六倍体杂种，并对其进行了细胞学鉴定、气孔观察以及一些生理生化特性的分析。在染色体记数、原位杂交和分子标记印证的基础上，比较了两种不同染色体加倍方法的效率。生理生化分析显示，六倍体杂种植株叶片的游离脯氨酸含量、质膜相对透性、Vc含量和叶绿素含量与三倍体杂种植株相比都有明显的差别。

English. Interspecific hybridization between Brassica species is an important way to create new resources and combine the valuable characters of different species, which is widely used in plant breeding. 120 plants of triploid hybrid（ABC, n = 27） derived from cross between B. carinata（BBCC,2n = 34） and B. rapa（AA,2n = 20）was obtained which played a important role in creating bridge materials for other Brassica species with one or two of the three genomes, 80 % of the hybrid plants had expected 27 chromosomes and showed intermediate characteristics. RAPD markers also verified the true hybrid nature. Two ways were used for chromosome doubling, one was that the 0.05 % colchicine solution was dropped on the growing point, another was that the seedlings were dipped into the 0.05 % colchicine solution for 8 hours, the ratio for chromosome doubling varied much between two methods. GISH results revealed that 16 strong signals could be sharply distinguished from other 38 chromosomes, which indicated the hexaploid hybrid came from chromosome doubling of triploid hybrid directly. Compared with triploid hybrids, the stomata size in hexaploid（AABBCC,2n = 54）hybrids was 1.65 times larger than that in triploidson the average. Otherwise, the stomata density of triploids was 1.83 times higher than that of hexaploids. It was also found that, except the electrical conductivity, all of biochemical measurements, such as the contents of proline（Pro） ,vitamine C（Vc）and chlorophyll, were higher in the hexaploid hybrids than that in triploid.