青藏高原东缘高寒草甸36种菊科植物果皮微形态特征研究  

A study on fruit coats micro-morphological characters of thirty-six species of Compositae from alpine meadow in eastern Qinghai-Tibet Plateau

作　　者：陈学林[1] 景国海[1] 

机构地区：[1]西北师范大学生命科学学院

出　　处：《草业科学》2007年第5期9-15,共7页Pratacultural Science

基　　金：西北师范大学植物学重点学科经费项目;国家自然科学基金项目(30470307)

摘　　要：对青藏高原东缘高寒草甸分布的菊科5属36种常见植物的果皮微形态特征进行了扫描电镜观察研究,结果表明:火绒草属植物代表特征为瘦果表面具纵波纹,香青属植物瘦果表面具舌状突起或网纹,蒿属植物瘦果表面的纵棱上具有横纹,千里光属植物瘦果表面的纵棱上具细条纹或不规则网纹,蒲公英属植物瘦果表面密被微刺。果皮微形态特征在各属植物内的演化趋势是:香青属植物瘦果表面的网纹与舌状突起相比可能是较为原始的,蒿属植物瘦果表面纵棱上的横纹存在显著变异,纵棱上具较明显的横纹应该是较进化的类型;千里光属植物瘦果表面纵棱上的网纹可能由条纹演化而来。果皮微形态结构具有一定的生态学意义,蒿属植物瘦果表面的胶质可以吸附小颗粒形成一个躲避干旱的微环境,或快速吸水以萌发或是进行粘液停泊,也有利于进行动物体外传播。千里光属植物和蒲公英属植物瘦果表面的纵棱更为突起,可能有利于吸附小颗粒和控制表面温度,蒲公英属植物瘦果表面的微刺可能有利于2次传播。A study on fruit coats micro-morphological characters of thirty-six familiar plant species of Compositae from alpine meadow in eastern Qinghai-Xizang Plateau were carried out by SEM. The results showed the representative characteristic of Leontopodium is lengthways ripple on achene surface;. Ligule protuberance or reticulation appears on achene surface in Anaphalis. Artemisia and Senecio have transverse stripe, reticulation or lengthways thin stripe on lengthways ridge on achene surface, respectively. There is dense spinule on achene surface in Taraxacurn. Evolution trend of fruit coats micro-morphological characters within each genus is explored as following. Compared with the ligule protuberance on achene surface, the reticulation may be primordial in Anaphalis. The transverse stripe on lengthways ridge of achene surface in Artemisia is variable, and the type with more obvious transverse stripe may be evolutionary. The reticulation on lengthways ridge of achene surface may have evolved from stripe of Senecio. Fruit coats micro-morphological characters are of some ecological significance. Mucilage on achene surface in Artemisia can absorb small particles to create a microclimate for avoiding drying damage or absorbing water quickly to germinate. It is also useful for myxospermy or epizoochore. Ridges on achene surface in Senecio and Taraxacum are useful for absorbing small particles or controlling surface temperature. Spinule on achene of Taraxacum may be fit for epizoochore.

关 键 词：菊科 果皮微形态 高寒草甸 青藏高原 

分 类 号：Q944[生物学—植物学]