Allozyme variation and the genetic structure of populations of Trochodendron aralioides, a monotypic and narrow geographic genus

Citation
Je. Wu et al., Allozyme variation and the genetic structure of populations of Trochodendron aralioides, a monotypic and narrow geographic genus, J PLANT RES, 114(1113), 2001, pp. 45-57
Citations number
61
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Plant Sciences
Journal title
JOURNAL OF PLANT RESEARCH
ISSN journal
0918-9440 → ACNP
Volume
114
Issue
1113
Year of publication
2001
Pages
45 - 57
Database
ISI
SICI code
0918-9440(200103)114:1113<45:AVATGS>2.0.ZU;2-4
Abstract
Allozyme diversity was analyzed to determine the genetic structure of popul ations of Trochodendron aralioides Siebold & Zucc., a primitive angiosperm that is insect pollinated, has wind-dispersed seeds and grows only in easte rn Asia. Nineteen populations were analyzed, including 16 from Taiwan, two from the main islands of Japan and one from Iriomote Island in the Ryukyu I slands. Genetic variability (0.133) at the species level was more similar t o that of a narrow geographic species than an endemic species. Based on gen otype frequencies, mating within populations was non-random (F-IS=0.065) an d there was significant genetic differentiation (F-ST=0.164) among populati ons. Genetic diversity was largely within, rather than among, populations ( H-S=0.132, 85.14%). Bisexual flowers of T. aralioides exhibit synchronized dimorphism. The protogynous and protandrous morphs are self-incompatible, w hich probably promotes outcrossing and contributes to the high levels of he terozygosity within populations. Using a maximum likelihood tree, populatio ns of T. aralioides were separated into two distinct clusters: Japan and Ta iwan/ Iriomote Island. Populations of T. aralioides on Iriomote Island and in northern Taiwan exhibited a high degree of genetic similarity. The isola tion-by-distance model does not fit populations in Taiwan, but suitably des cribes the relationship between populations of T. aralioides in Japan and T aiwan.