摘要
本文报道了贵州苏铁(Cycas guizhouensis)的染色体数目及核型,并与攀枝花苏铁(C.panzhihuaensis)、苏铁(C.revoluta)、华南苏铁(C.rumphii),拳叶苏铁(C.circinalis)和C.media等的核型进行了比较,讨论了苏铁属植物不同核型的进化趋势,提出了苏铁属植物的两种地理分布核型,即1.北回归线以北为K(2n)=22=2m+4sm+4st+12T包括贵州苏铁和攀枝花苏铁;2.北回归线及其以南为K(2n)=22=4m+8st+10T,包括苏铁、华南苏铁、拳叶苏铁和C.media。
In the present paper the chromosome number and karyotype of Cycas guizhouensis are reported, and they are compared with those of C. panzhihuaensis、C. revoluta、C. rumphii, C. circinalis and C. media. The karyotype formula of C. guizhouensis is K(2n)=22=2m+4sm+4st+12T identical to C. panzhihuaensis. Both species distribute in the north of the Tropic of Cancer. The karyotype of C. guizhouensis is more advanced than many other species of the genus Cycas such as C. revoiuta, C. rumphii, C. circinalis and C. media which are known to be K(2n)=22=4m+8st+10T and distribute in the south of the Tropic of Cancer. On the other hand. C. guizhouensis is more primitive than C. pa- nzhihuaensis.
出处
《植物学通报》
CSCD
1990年第3期45-48,共4页
Chinese Bulletin of Botany
关键词
苏铁
核型分析
Cycas guizhouensis
Karyotype
