摘要： 利用扫描电子显微镜对10个品种的长山药花粉形态进行了观察和对比研究,结果表明:长山药花粉形状为扁球形,两端平截,2沟,极轴长11.51μm(10.02～13.90μm),赤道轴长18.53μm(16.21～21.05μm),属于小型的花粉(10～25μm)。10种长山药品种花粉在极轴、赤道轴和P/E比值上均部分存在显著差异。外壁纹饰为网状、穴网状、孔穴状三类。利用SAS9.0软件,根据不同品种的长山药花粉外部形态特点,对其进行赋值,做Q聚类分析。结果表明,在遗传距离7.75时,可将10个长山药品种分为3类。第一类包括毕克齐长山药和逃墙山药,其特点为极面观近圆形,花粉较小,外壁纹饰呈孔穴状;第二类包括嘉祥细毛山药、太怀山药、侯马山药、惠楼小红皮、孙付吉山药和河北保定山药,花粉体积中等,其中太怀山药为穴网状纹饰,其他山药为网状纹饰;第三类是华县山药和日本山药-2,华县山药穴网状纹饰,日本山药-2为孔穴状纹饰。

关键词: 长山药, 扫描电镜, 花粉形态, 分类

Abstract: Pollen grains of 10 Chinese yam(Dioscorea opposita Thunb.)were observed by scanning electron microscope(SEM).The results showed that the pollen shape of 10 Chinese yam(Dioscorea opposita Thunb.)is spheroidicity with both flat ends and 2 anasulcates.The polar axis length is 11.51 μm(10.02-13.90 μm)and the equatorial axis length is 18.53 μm(16.21-21.05 μm).It is a small pollen(10-25 μm).There were some significant differences on pollen of 10 Chinese yam(Dioscorea opposita Thunb.)in the long polar axis,equatorial axis and P/E ratio respectively.Exine ornamentation is reticulate,foveolate-reticulate,cavernous categories.The result of Q-cluster analysis based on pollen morphology and characteristic indicated that 10 Chinese yam could be classified into three groups when genetic distance was 7.75.The groupⅠincluded Bikeqi Yam and Taoqiang Yam with their small pollen grains,nearly round equatorial view and cavernous exine sculpture.The groupⅡincluded Jiaxiang Yam,Taihuai Yam,Houma Yam,Huilou red peel Yam,Sunfuji Yam and Baoding Yam with medium pollen grain.Taihuai Yam exine sculpture was foveolate-reticulate ornamentation and the other matereils were all reticulate ornamentation.The groupⅢincluded Huaxian Yam and Japan Yam-2 with larger pollen grain and reticulate ornamentation and cavernous ornamentation respectively.

Key words: Chinese yam(Dioscorea opposita Thunb.), SEM, Pollen morphology, Classification

中图分类号: 

• S632.1