Plant Diversity ›› 2014, Vol. 36 ›› Issue (01): 13-21.

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New Chromosome Counts and Their Taxonomic Implications in Primulina sensu lato (Gesneriaceae)

 LIU  Rui-Rui-1、2, SKOG  Laurence E.4, LIAO  Jing-Ping-1, ZHOU  Tai-Jiu-3, WEN  Fang-3   

  1. 1 South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China; 2 University of Chinese Academy
    of Sciences, Beijing 100049, China; 3 Guangxi Institute of Botany, Guangxi Zhuangzu Autonomous Region and Chinese
    Academy of Sciences, Guilin 541006, China; 4 Botany Department, MRC166, Smithsonian Institution,
    National Museum of Natural History, Washington, D.C. U.S.A
  • Online:2014-01-25 Published:2014-12-01

Abstract:

Chromosome numbers can be helpful in understanding the taxonomy and phylogenetic patterns within plant groups. Primulina sensu lato (s. l.), a genus that has recently been redefined and expanded to include all species of Chiritopsis, two of Wentsaiboea and all of section Gibbosaccus of Chirita, has not been well documented cytologically. In the present study we determined the chromosome numbers of fourteen species, three varieties and seven undescribed taxa of Primulina s. l. using conventional rapid squash techniques. In addition, three species of its closest ally, Petrocodon sensu lato (s. l.), were also investigated cytologically. With the exception of Primulina tabacum, all counts are new. A high stability of chromosome number, 2n=36, based on x=18, was recorded in Primulina s. l. Chromosomes were relatively small in size, with mostly metacentrics and submetacentrics predominating. Although slight variation in chromosome size occurs among taxa, the overall homogeneity of chromosome morphology and pattern of basic chromosome number conforms with the results of molecular phylogenetic studies, which strongly support the monophyly of Primulina s. l., and also recent taxonomic treatment. Interestingly, the possession of the same chromosome numbers together with similar chromosome morphology, indicates that Primulina s. l. and Petrocodon s. l. are closely related, which is consistent with the molecular phylogeny of these genera.

Key words:  Chromosome numbers, Chromosome morphology, Petrocodon sensu lato, Primulina sensu lato, Taxonomic treatments

CLC Number: 

  • Q 942