|
Yushania niitakayamensis is a member of grass family. In Taiwan,
the species occurs in the central mountain ranges from 1000 to
3600 m in altitude. The plant height range from 10 cm to 5 m
according to ecological habitats. In exposed high mountain
environments the species usually form pure stands about 20 to 60
cm in height, while in shaded areas of forest habitat, it can
reach aheight of 5 m. The species appears to spread mainly by
rhizomes and flower rarely, leading to the prediction that
most populations may be comprised of a single or a few clonal
genotypes and that the observed morphological variationmay be
primarily due to phenotypic plasticity. In the present study,
samples were collected from various habitats around the island.
Twenty samples were collected at a 15 m intervals across a
transet from each population. Sampling sites of higher altitudes
generally consisted of open and shaded habitats while those
of lower altitudes generally consisted of shade habitat only.
The genetic variation of the species was analysed using the
method of RAPD. The within population variation was found to
occur in every population. The resultof cluster analysis
indicated that the populations, with some exceptions,
generally diversified according to geographical differences. The
populations of higher altitudes were found to be more similar
genetically. The result of AMOVA (Analysis of Molecular
Variance) analysis revealed that among the total variation,
12.00% of the variation was attributable to differences among
locations, 9.05% of the variation was attributable to
differences among populations within locations, and 78.95%
of the variation was attributable to differences among
individuals within populations. Most variation was found to be
resided among individuals within populations.
|