摘要
【目的】对青藏高原东缘6属32种菊科植物连萼瘦果的大小及其变异进行了比较,并探讨了影响连萼瘦果大小变异的环境因素。【方法】采集青藏高原东缘6属32种菊科植物的连萼瘦果,测算其长度、宽度和长/宽3项指标,并对上述指标与植物分布海拔高度的相关性进行了分析。【结果】①橐吾属(Ligularia)连萼瘦果平均长度最大,亚菊属(Ajania)、香青属(Anaphalis)和蒿属(Artemisia)连萼瘦果平均长度较小;紫菀属(Aster)和橐吾属的平均宽度相对较大;长/宽的平均值在各属间相差很大,最大的为千里光属(Senecio),蒿属最小。②蒿属、紫菀属、亚菊属和千里光属的连萼瘦果长度、宽度分别与海拔呈正相关性,且连萼瘦果长度与宽度也呈正相关性;橐吾属和香青属的连萼瘦果长度、宽度分别与海拔呈负相关性,但连萼瘦果长度与宽度呈正相关性。③在连萼瘦果大小变异方面,亚菊属、千里光属和香青属连萼瘦果长度的变异系数较小,蒿属、紫菀属和橐吾属的变异系数较大;香青属连萼瘦果宽度的变异系数较小,其他属的变异系数相差不大。【结论】6属菊科植物的连萼瘦果大小及变异差别较大,反映出菊科植物的不同进化水平;海拔是影响菊科植物连萼瘦果大小及变异的一个重要因素。
【Objective】 The cypsela size and variation of 6 genera（32 species） about Compositae of eastern Qinghai-Tibetan Plateau were studied and the environmental facts were discussed.【Method】 The cypsela of 6 genera（32 species） from eastern Qinghai-Tibetan Plateau were collected.The length,width and length/width of the cypsela were computed,then the relativity about the length,width,length/width of the cypsela and altitude were analyzed.【Result】 The results show that：①The mean length of Ligularia is the biggest,and the mean length of Ajania,Anaphalis and Artemisia is the smallest;the mean width of Aster and Ligularia is bigger than that of others;the mean length/width have lots of differences,the biggest being Senecio,and the smallest Artemisia.② The cypsela length and width of Artemisia,Aster,Ajania and Senecio respectively have plus relativity with altitude,and the cypsela length and width also display plus relativity;the cypsela length and width of Ligularia and Anaphalis respectively have minus relativity with altitude,but the cypsela length and width display plus relativity.③At cypsela size variation,the cypsela length variations of Ajania,Senecio and Anaphalis are smaller,the cypsela length variations of Artemisia,Aster and Ligularia are bigger;the cypsela width variation of Anaphalis is smaller,and others have little difference.【Conclusion】 The cypsela size and variation have big differences between 6 genera.It reflects diverse evolutive level.The altitude is an important factor affecting the size of cypsela and its variation.
出处
《西北农林科技大学学报（自然科学版）》
CSCD
北大核心
2008年第10期207-214,共8页
Journal of Northwest A&F University(Natural Science Edition)
基金
国家自然科学基金项目(30470307)
关键词
青藏高原东缘
菊科
连萼瘦果
eastern Qinghai-Tibetau Plateau
Compositae
cypsela
