Abstract
The genus Castanea (Fagaceae), which contains three sections and seven species, is widely distributed in the deciduous forests of the Northern Hemisphere. The phylogeny of Castanea was estimated using DNA sequence data from five different regions of the chloroplast genome. Sequencing results support the genus Castanea as a paraphyletic group with C. crenata, the Japanese chestnut, representing an early divergence in the genus. The three Chinese species form a strongly supported sister clade to the North American and European clade. A unique westward expansion of extant Castanea species is hypothesized with Castanea originating in eastern Asia, an initial diversification within Asia during the Eocene, followed by intercontinental dispersion and divergence between the Chinese and European/North American species during the Oligocene and a split between the European and North American species in the early Miocene. The differentiation within North America and China might have occurred in late Miocene or early Pliocence. The North America species are supported as a clade with C. pumila var. ozarkensis, the Ozark chinkapin, as the basal lineage, sister to the group comprising C. pumila var. pumila, the Allegheny chinkapin, and C. dentata, the American chestnut. Morphological evolution of one nut per bur in the genus may have occurred independently on two continents.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.