几种杨柳科植物成熟冠毛形态观察与比较

通过对黄花柳、五蕊柳、小叶杨、加杨、山杨和小青杨等6种杨柳科植物成熟果实冠毛的观察,发现:杨柳科这几种植物的冠毛外型差异不大,冠毛为中空,基部(着生在胎座上的一端)壁较厚,是整个毛中壁最厚的部分,具明显的褶皱与横纹;基部略向上一些,壁开始逐渐变薄的地方,冠毛的内径有一明显增大,是整个冠毛直径最大处;接近尾部时,毛的直径逐渐变小,成为一个实心的芒端。杨柳科这几种植物的冠毛从外形上看差异不大,很难作为野外工作中的分类依据。但是冠毛的各形态指标确实有一定的差别,统计分析表明大多差异显著。

Observations and Comparisons on Morpha of Mature Pappi of Several Salicaceous Plants

Through the observation of pappi of mature fruits of 6 salicaceous plants(Salix caprea,Salix pentandra,Populus simonii,Populus×canadensis,Populus davidiana,Populus pseudo-simonii),it is founded that these plants in poplar and osier family have similar morpha of pappus.Pappi are hollow and the wall of basal pappi(inserting on placenta) is stoutest in the whole pappus,with placation and transverse.The upper wall of basal plume begins to be fine.The bore of plume are visible enlargement and the biggest in all the diameter of the whole pappus.The adjacent pygidial plate become smaller and smaller,even solid cecum.It is difficult to apply these characters to taxonomic index,but statistical analysis shows visible difference.