Background and (Asteraceae) are narrowly and allopatrically distributed varieties, separated from the important biogeographic boundary Tanaka Collection in Southwest China. allopatric divergence. Electronic supplementary material The online version of this article (doi:10.1186/s12862-015-0374-5) contains supplementary material, which is available to authorized users. Franch. and Kurz, both belonging to the Mutisieae (Asteraceae) [14], are characterized by woody growth form and rare in China. is definitely a monotypic genus endemic to southwest China and contain two extant varieties, one of which occurred in Yunnan China. and are not sharply divergent morphologically but differ most prominently in flora characteristics. has capitula inside a dense terminal cyme and tubular florets, whereas is definitely characterized with several, solitary, terminal and radiate capitula, and fertile florets with marginal uniseriate, bilabiate florets, and central tubular florets [15]. Despite the little distinctively morphological differentiation, they may be closely related phylogenetically: and were considered to be self-employed and treated as group based on morphological heroes [14, 16]; and then molecular studies based on chloroplast DNA variance in Panero and Funk showed they clustered collectively within a clade that also contains the South American genera and [17]; later Funk et al. regarded as them a and are tightly related, differing from additional Asian or American varieties of Asteraceae. and are allopatric over their natural ranges. has a large distribution range, extending from south Asian countries like Myanmar, Thailand and Vietnam to China, whereas has a more restricted distribution in Yunnan and Sichuan in China [21]. They both can grow in valleys with dry and sizzling environmental condition; however, in contrast, also prefers the edge of the forest and isolated mountaintops [22, 23]. In particular, the distribution ranges are found to coincide with known the biogeographic boundary, i.e. Tanaka Collection, which separates two environmentally divergent subkingdoms, that is the Sino-Himalayan Forest to the west and the Sino-Japanese Forest to the east [24C26]. Although it is not an apparent physical barrier like mountain ranges, river systems or sea straits, deep divergences between the 94-62-2 boundary have been reported (such as [27C30]). Taking the reason into account, one recent phylogeographic study supported the dramatic climate changes during the (Past due) Pleistocene, when the presently differing monsoon regimes on either part of the Tanaka Collection founded, may be a reasonable explanation for the divergence [31]. However, for studies with adequate sampling from areas proximal to and/or along the Tanaka Collection are still lacking, assessing the feature like a genetic boundary remains mainly hypothetical. Based on the distribution range and closely related relationship, these 94-62-2 Rabbit Polyclonal to AIFM1 two varieties may provide a model to study the present genetic variance and assess whether there is long-term populace isolation without migration 94-62-2 across the Tanaka Collection. Although, previous study using molecular sequences hypothesized the recent origins and phenotypic development via adaptation to dry and awesome habitats during the Quaternary glaciation; however, only a small number of populations of and and only one individual per populace were sampled in the above molecular investigation. Therefore, more comprehensive analyses based on a sufficient populace sampling of both varieties are needed to address the population genetic differentiation and to investigate historic demography of the two species. In the present study, we compared sequence variance at both cpDNA fragment and the low-copy nuclear gene, across a large number of individuals and populations covering the natural ranges of and in China. Specifically, we aim 94-62-2 to determine the amount of sequence divergence and possible gene circulation after divergence between and and were collected in the field and dried directly with silica gel. We sampled 11 natural populations of and 16 of [33] was amplified and sequenced. We adopted our previous study in sequencing chloroplast DNA [34]. In addition, we selected one single or low-copy nuclear locus to estimate the genetic diversity and geographic structure of the two varieties. The granule-bound starch synthase gene (or gene, it was amplified and sequenced using the pair of primer (5-ACA TTG CYT ACC AAG GNA GA-3) and (5-AAC TGA ATG AGA CCA CAM GG-3) in the initial phase of the study, designed from the complete coding sequence of (Conolvulaceae, “type”:”entrez-nucleotide”,”attrs”:”text”:”AB071976″,”term_id”:”15778157″,”term_text”:”AB071976″AB071976) [42] and its homologous sequences using the program Primer Leading 5.0. The acquired sequences were blasted for sequence homology to ensure.