茴芹属16种植物的花粉形态及系统学分析

利用光学显微镜和扫描电镜对茴芹属16种植物的花粉形态进行了观察,其中12种为首次报道。结果表明,茴芹属16种植物花粉大小为（19.75～33.03）μm×（11.52～17.41）μm,极轴与赤道轴的比值（P/E）为1.40～2.28,体积大小指数（P×E）^1/2为16.71～23.97,属于中型花粉,具三孔沟,萌发孔位置为边萌发孔。花粉粒赤道面观有近矩形、赤道收缩形、椭圆形和近菱形等类型,其中近矩形和赤道收缩形占多数;极面观为三角形或三角圆形。扫描电镜下,其外壁表面纹饰赤道面观为脑纹状,极面观近光滑或为穴纹状。在伞形科芹亚科中,茴芹属植物的花粉具有中等进化、比较进化的形态特征。研究认为,花粉形态可为个别物种的分类处理提供孢粉学证据。

Pollen Morphology of Sixteen Pimpinella Species (Apiaceae) and the Systematic Analysis

In this test,pollen morphology of sixteen species of the genus Pimpinella from China was investigated by light microscopy（LM） and scanning electron microscopy（SEM）.Of all species that involved,the pollen morphology of twelve species was documented for the first time.The result shows that the grains fall in the medium range of the size classification with the size of（19.75³3.03） μm×（11.52¹7.41） μm,and P/E value of 1.40².28 while the grain size index （P×E）^1/2 falling in the range of 16.71²3.97.These grains are all tricolporate,having pleurotreme,with mainly subrectangular or equatorially constricted shape in the equatorial view and triangular or triangular-rounded shape in the polar view.Under the SEM,cerebroid-type grain sculpture is shown in the equatorial view and smooth or pitted-type sculpture in the polar view.It reveals that Pimpinella species have moderately or more derived pollen morphological features in the family Apiaceae subfamily Apioideae.Furthermore,pollen morphology can provide evidences for the taxonomic treatment for several Pimpinella species.