苍耳Xanthium strumarium L. 染色体数目和核型的观察

苍耳Xanthium strumarium L.(X. sibiricum Patr. ex Widder, X. iaponicum Widder)为菊科苍耳属的一年生草本,广布于欧亚大陆和北美洲;我国各地也均有分布。苍耳为常用中药,其果实入药,能发汗通窍、祛风湿,解表镇痛,用于治风湿性关节痛及鼻炎等症。

EXAMINATION OF CHROMOSOME NUMBERS AND KARYOTYPE OF XANTHIUM STRUMARIUML

Xanthium strumarium L., the fruits of which are used as a remedy for rheumatoid arthritis and rhinitis in traditional Chinese medicine, is a common weed distributed all over China. The present paper deals with a study of the chromosome numbers and karyotypic analysis for X. strumarium. The seeds used for examination were collected from 30 habitats belonging to 20 provinces and autonomous regions of China. The number of chromosomes in root tip cell has been found to be 2n=36, in accord with those reported by many previous authors. However, aneuploidy with 2n = 34 and 35 within individual plant is of frequent occurrence.In the light of chromosomal terminology defined by Levan and al., the karyotype formula of X. strumariura is 2n = 36 = 26m + 2m(SAT)+8sm, and belongs to Stebbins' "2B" type of karyotypic asymmetry.The cytological information obtained through the present study does not give support to the specific segregation of the X. strumarium complex.