缙云山自然保护区常见菊科植物花粉形态特征分析

Study on Pollen Morphology of Compositae in Jinyun Mountain Nature Reserve

应用光学显微镜对缙云山自然保护区17种常见菊科植物的花粉形态进行了观察和分析,结果显示花粉粒均为辐射对称,大多为近球形—长球形,萌发孔均为三孔沟,极面观为三裂圆形.根据花粉形态特征分析,17种菊科植物花粉类型可分为4大类:①花粉形态以粗大网状纹饰为主要特征,以黄鹌菜、苦荬菜、雷山假福王草、假福王草植物为代表;②花粉形态以刺尖、刺密、刺长为主要特征,以向日葵族的白花鬼针草、牛膝菊、豨莶、狼杷草最为明显;③花粉形态以刺基部大、刺较钝为主要特征,以蒲儿根、千里光、东风草和马兰为代表;④花粉形态以刺稀疏、较短、刺上下均匀为特征,以南川斑鸠菊、鳢肠、野茼蒿、鼠麯草为代表.但是,并不是所有的都能有这样较好的对应关系,花粉形态相似的植物可能来自于不同的族属.

Pollen morphology of 17 compositae plants from Jinyun Mountain Nature Reserve in Chongqing Municipality are observed and analyzed under light microscope （LM）. The results show that the pollen grains are radially symmetrical, spherical or subsphaeroidal in shape, and the polar view is 3-1abed-rounded. They all have 3 colporates. By their pollen morphological features, the 17 species are divided into 4 types. （1） The pollen has big reticulation veins. The representative plants are in three genera： Yoμngia japonica （L.） DC, Ixeris polycephala Cass, Paraprenanthes heptantha Shih et D.J. Liou and P. sororia （Miq.） Shih. （2） The pollen is characterized by sharp, dense and long spines. The representative plants are in four gen- era： Bidens Pilosa L. , Galinsoga parviJTora Cav. , Siegesbeckia orientalis L. and Bidens tripartite L. （3） Its main characteristics are that the base of spine is swelling and the spine is blunt. The representative plants are in four genera： Sinosenecio oldhamiaus （Maxim.） B. Nord, Senecio scandens Buch. -Ham, Blumea rnegacephala （Randeria）Chang et Tseng and Kalimeris indica （L.） Sch. -Bip. （4）This type is characterized by sparse, short, and uniform spines. The representative plants are in four genera： Vernonia cumingiana Diels, Crassocephalumcrepidioides （Benth.） S. Moore （Gynura crepidioides Benth）, Eclip- ta prostrate L. and Gnaphaliμm of fine D. Don. Pollen morphology is different between different plants, but plants with similar pollen morphology can come from different tribes-genera.