Abstract
Species in the genus
Castanea are widely distributed in the deciduous forests of the Northern Hemisphere from Asia to Europe and North America. They show floristic similarity but differences in chestnut blight resistance especially among eastern Asian and eastern North American species. Phylogenetic analyses were conducted in this study using sequences of three chloroplast noncoding
trnT-L-F regions. The
trnT-L region was found to be the most variable and informative region. The highest proportion of parsimony informative sites, more and larger indels, and higher pairwise distances between taxa were obtained at
trnT-L than at the other two regions. The high A+T values (74.5%) in the
Castanea trnT-L region may explain the high proportion of transversions found in this region where as comparatively lower A+T values were found in the
trnL intron (68.35%) and
trnL-F spacer (70.07%) with relatively balanced numbers of transitions and transversions. The genus
Castanea is supported as a monophyletic clade, while the section
Eucastanon is paraphyletic.
C. crenata is the most basal clade and sister to the remainder of the genus. The three Chinese species of
Castanea are supported as a single monophyletic clade, whose sister group contains the North American and European species. There is consistent but weak support for a sister-group relationship between the North American species and European species.
Keywords
Fagacae,
Castanea,
trnT-L-F,
Phylogenectics
Citation
Lang, Ping; Dane, Fenny; Kubisiak, Thomas L. 2005. Phylogeny of
Castanea (Fagaceae) based on chloroplast
trnT-L-F sequence data. Tree Genetics & Genomes, Vol. 2: 132-139