摘要
国产白酒草亚族(菊科紫菀族)由白酒草属(Conyza)、小舌菊属(Microglossa)和歧伞菊属(Thespis)3个小属组成,且国产白酒草亚族各属间及其与非洲白酒草属植物之间的分子系统发育关系尚无报道,故本研究利用核糖体DNA ITS和ETS序列并采用最大简约法和贝叶斯分析法,重建了国产白酒草亚族的分子系统发育树。结果表明,国产4种白酒草属植物、歧伞菊和非洲白酒草属植物组成一支,而劲直白酒草的两变种和小舌菊嵌入田基黄亚族分支;小舌菊与Psiadia pascalii近缘。基于这些结果,我们认为:(1)劲直白酒草和Conyza incisa应处理为田基黄亚族的一个独立的属;(2)国产4种白酒草属植物和歧伞菊以及大多数非洲白酒草属植物属于Eschenbachia属,而且Eschenbachia属代表一个新的亚族,歧伞菊可处理为Eschenbachia属的一个组。Eschenbachia属可能从非洲经数次长距离传播到达我国南部;(3)Welwitschiella和小舌菊属应保持属的地位,Psiadia pascalii、Conyza scabrida和C.pyrrhopappa可并入小舌菊属。
Chinese subtribe Conyzinae （Asteraceae： Astereae） consists of three small genera, Conyza, Microglossa and Thespis. To date, however, the molecular phylogenetic relationships among African Conyza, and Chinese Conyza, Thespis and Microglossa have not been investigated. The internal and external transcribed spacers of nuclear ribosomal DNA were used to reconstruct the phylogeny of Chinese Conyzinae through maximum parsimony and Bayesian analyses. Results showed that four Chinese Conyza species and Thespis divaricata belonged to a clade with most sampled African Conyza, whereas two Conyza stricta varieties and Microglossa pyrifolia were embedded deeply within the subtribe Grangeinae clade. Microglossa pyrifolia was closely related to Psiadia pascalii. Based on phylogeny, we considered that （ 1 ） C, stricta and C, incisa should be treated as a separate genus that belongs to subtribe Grangeiane; （2） four Chinese Conyza, Thespis and most sampled African Conyza belong to the genus Eschenbachia. Eschenbachia should belong to a new separate subtribe, while Thespis should be treated as a section of Eschenbachia. Eschenbachia may have arrived at southern China by several long-distance dispersals from Africa~ （3） it is reasonable to maintain the generic status of Welwitschiella and Microglossa and treat Psiadia pascalii, C. scabrida and C. pyrrhopappa as members of Microglossa.
出处
《植物科学学报》
CAS
CSCD
北大核心
2014年第3期216-227,共12页
Plant Science Journal
基金
国家自然科学基金资助项目(31370265)
湖南省生态学重点学科建设项目资助
湖南省教育厅科学研究基金资助(08A046)
