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Studies of Species Differentiation in Smilax and Heterosmilax (Smilacaceae)

Author: WangAiLi
Tutor: FuChengXin
School: Zhejiang University
Course: Botany
Keywords: Smilax Xiao Smilax Karyotype and inflorescence evolution Smilax species complex Allozyme Polyploid Speciation
CLC: Q941
Type: Master's thesis
Year: 2006
Downloads: 73
Quote: 1
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Abstract

In this study, cytology, morphology and molecular systematics multidisciplinary approach and method Smilax research and Shaw Smilax Smilax species complex, explore of the the Smilax and Shaw Smilax nuclear type and inflorescence evolution characteristics and Smilax Smilax species complex phylogenetic relationship, the main findings are as follows: 1. Smilax and Shaw Smilax sarsaparilla genus Smilax Branch 15 somatic karyotype and inflorescence characteristics and Shaw Smilax system evolution of inflorescence and nuclear characteristics of the system evolution analysis, based on research karyotype characteristics and existing molecular sequence data, the analysis of the evolution of their system. That: (1) the entire taxa karyotypic variation in performance in the Type II, polyploidy, chromosome micro variability and the chromosome number of descending (from 16-15-13), 16 Smilax basic chromosome number of taxa; (2 ) the herb sarsaparilla nuclear type symmetry in East Asia to the North American species showed changes from symmetric to asymmetric woody sarsaparilla between the groups did not show this trend; (3), first-out leaves persistent bud scales, in of Smilax groups and soil Poria group in inflorescence branching (the base of the branches with leaves first) cone Smilax group and Sui Smilax group of axillary inflorescence branches or The umbel joint homologous; combined with ITS data, inflorescence original type is the peduncle was arranged spicate species with umbels. From ancestors, inflorescence formed two branches: one for the majority of taxa the Smilax and Shaw Smilax on behalf of the axillary umbel or umbrella - panicles, another group Sui Smilax The spicate arranged no peduncle umbel. (4) Xiao Smilax from karyotype and ITS data show that the non-monophyletic group, herb sarsaparilla and soil the Poria group members as the sister group to support Xiao sarsaparilla is reduced to the subgenus placed sarsaparilla is ; (5) karyotype features support herb sarsaparilla East Asian origin, extended to North America, and soil the Poria group types have a common ancestor, from x = 16 woody Smilax endorse recovery herbs group (sect.Nemexia): ( 6) was first discovered in a widely distributed species of Smilax diploid populations, there are three ploidy (2x, 4x and 6x), found that the populations of different ploidy distribution pattern, suggesting that the mid-Tertiary to Pleistocene Japan, Taiwan and the mainland before the separation, Smilax 4x populations has been widely distributed, widely distributed 6x populations formed after the separation of the island to the mainland; (7) in southwest China Smilax Branch modern distribution and differentiation. 2. Firstly use allozyme means species of Smilax species complex formation on the relationships between species and species of Smilax species complex formation, the the zymogram analysis shows that black fruit does not belong Smilax Smilax species complex. The Smilax complex is a change from diploid to hexaploid a series karyotype groups, this study further confirm the sarsaparilla diploid populations, as well as the small fruit of the diploid sarsaparilla and three-pulse Smilax genetic relationship between the stans, they may very Smilax tetraploid and hexaploid one of the parents, or at least the presence of several genes penetration. Zymography reveals widely distributed species Smilax two tetraploid populations - populations in Guangxi and Guizhou heterologous

Studies of Species Differentiation in Smilax and Heterosmilax (Smilacaceae)

Abstract

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