11种杨属植物的倍性鉴定及山杨天然三倍体的发现

Ploidy Testing of 11 Poplar Species and Discovery of Natural Triploid Populus davidiana Dode

在西藏芒康的山杨居群中发现有叶型明显偏大的山杨植株,通过与该地其他居群正常山杨的叶型比较推测其为三倍体山杨,后经流式细胞述验证了上述推测,确定为中国首次发现的山杨天然三倍体植株,同时以白杨组物种山杨和圆叶杨,青杨组物种冬瓜杨、梧桐杨、康定杨、滇杨、川杨、青杨、辽杨、德钦杨及大叶杨组大叶杨为研究对象,采用流式细胞仪对每个种代表样本的染色体倍性进行检测。结果表明:这11个物种全部为二倍体,青杨、辽杨、大叶杨的倍性与前人报道结果一致,其余8个种为首次报道。试验结果显示杨属物种的倍性相对稳定,没有发现四倍体。倍性研究结合叶片研究表明,在青杨组中叶形大小仅为不同种之间存在的形态上的差异,而在白杨组山杨中可能就是倍性的差异。

We found a large leaves form of Populus davidiana at Mangkang in in Xizang. Compared with leaves type between the big leaves aspen and norsmal aspen speculate the large one is triploid aspen. Then,we verified it using flow cytometry. It was the first time that the natural triploid aspen was reported. We used the flow cytometry to determine the ploidy level of the 11 species containing P. davidiana,P. rotundifolia in Section Leuce,P. lasiocarpa in Section Leucoides and P.cathayana,P. haoana,P. maximowiczii,P. pseudomaximowiczii,P. purdomii,P. yunnanensis,P. szechuanica,and P.kangdingensis in Section Tacamahaca. All 11 species were diploid. The results of P. cathayana,P. maximowiczii,P. lasiocarpa were the same with those of previous research,and the rest was reported for the first time. Results manifested that the species of the genus Populus shared stabilized ploidy level without tetraploid. Ploidy studies combining blade research show that the leaves size is the only morphological difference in different species in Section Tacamahaca,but it may be ploidy difference in species P. davidiana.