Fourteen additional microsatellite markers for Mussaenda pubescens and cross-species amplification

Abstract

Mussaenda pubescens Ait. f. is a species with stigmadimorphism and functional dioecy, with yellow flowers and well-developed petaloid calyx-lobes, which is widespread in southern Chinese provinces Fujian, Guangdong, Guangxi, Hainan, Hunan, Jiangxi, Taiwan and Zhejiang (Li et al. 2010). A new variety M. pubescens var. alba, with white, stout corolla and much reduced or even lack of the petaloid calyx lobes which is different from typical M. pubescens, is also widely distributed in southern China (Deng and Zhang 2004). However, the two varieties never grow together. M. pubescens grows in more open places than M. pubescens var. alba, and the latter usually grows together in more dense habitats with other congeneric species with yellow flowers, such as M. shikokiana, M. kwangtungensis and M. erosa. Samples with intermediate morphologies between M. pubescens var. alba, and the sympatric M. shikokiana and M. kwangtungensis have been observed and natural hybrids have been identified (Shi Chen unpublished data). Microsatellites have proven to be efficient genetic markers for species delimitation, phylogenetic reconstruction and detection of hybrids (Xu et al. 2004; Barkley et al. 2005; Zhan et al. 2008). Nineteen microsatellite markers for M. pubescens have been developed previously (Duan et al. 2012), but they could not provide sufficient variation in population genetic structure analyses and in detecting interspecific hybridization in Mussaenda due to low polymorphisms. Here, we report 14 additional highly polymorphic microsatellite markers and expect them to provide additional tools for evaluating the intraspecific and interspecific population genetic structure and detecting the potential hybrids.