title: Extensive hybridization and introgression between Melastoma candidum and M. sanguineum.
abstract: Natural hybridization can lead to various evolutionary outcomes in plants, including hybrid speciation and interspecific gene transfer. It can also cause taxonomic problems, especially in plant genera containing multiple species. In this study, the hybrid status of Melastoma affine, the most widespread taxon in this genus, and introgression between its putative parental species, M. candidum and M. sanguineum, were assessed on two sites, Hainan and Guangdong, using 13 SSR markers and sequences of a chloroplast intergenic spacer. Bayesian-based STRUCTURE analysis detected two most likely distinct clusters for the three taxa, and 76.0% and 73.9% of the morphologically identified individuals of M. candidum and M. sanguineum were correctly assigned, respectively. 74.5% of the M. affine individuals had a membership coefficient to either parental species between 0.1 and 0.9, suggesting admixture between M. candidum and M. sanguineum. Furthermore, NewHybrids analysis suggested that most individuals of M. affine were F2 hybrids or backcross hybrids to M. candidum, and that there was extensive introgression between M. candidum and M. sanguineum. These SSR data thus provides convincing evidence for hybrid origin of M. affine and extensive introgression between M. candidum and M. sanguineum. Chloroplast DNA results were consistent with this conclusion. Much higher hybrid frequency on the more disturbed Guangdong site suggests that human disturbance might offer suitable habitats for the survival of hybrids, a hypothesis that is in need of further testing.
authors.affiliation: State Key Laboratory of Biocontrol and Guangdong Key Laboratory of Plant Resources, Sun Yat-sen University, Guangzhou, China.
authors.forename: Ting
authors.initials: T
authors.lastname: Liu
authors.affiliation: School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou, China.
authors.forename: Yunyun
authors.initials: Y
authors.lastname: Chen
authors.affiliation: State Key Laboratory of Biocontrol and Guangdong Key Laboratory of Plant Resources, Sun Yat-sen University, Guangzhou, China.
authors.forename: Lifang
authors.initials: L
authors.lastname: Chao
authors.affiliation: State Key Laboratory of Biocontrol and Guangdong Key Laboratory of Plant Resources, Sun Yat-sen University, Guangzhou, China.
authors.forename: Shuqiong
authors.initials: S
authors.lastname: Wang
authors.affiliation: Key Laboratory of Plant Resources Conservation and Sustainable Utilization, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Wu
authors.affiliation: Guangzhou Institute of Landscape Gardening, Guangzhou, China.
authors.forename: Seping
authors.initials: S
authors.lastname: Dai
authors.affiliation: College of Pharmacy, Jinan University, Guangzhou, China.
authors.forename: Feng
authors.initials: F
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Biocontrol and Guangdong Key Laboratory of Plant Resources, Sun Yat-sen University, Guangzhou, China.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Fan
authors.affiliation: State Key Laboratory of Biocontrol and Guangdong Key Laboratory of Plant Resources, Sun Yat-sen University, Guangzhou, China.
authors.forename: Renchao
authors.initials: R
authors.lastname: Zhou
mesh_terms: D001499:Bayes Theorem; D002681:China; D002736:Chloroplasts / Q000378:metabolism; D018742:DNA, Chloroplast / Q000235:genetics; D021901:DNA, Intergenic; D005819:Genetic Markers; D005838:Genotype; D006239:Haplotypes; D006824:Hybridization, Genetic; D035322:Melastomataceae / Q000235:genetics*; D018895:Microsatellite Repeats; D008957:Models, Genetic; D011336:Probability; D013045:Species Specificity
chemical_list: D018742:DNA, Chloroplast; D021901:DNA, Intergenic; D005819:Genetic Markers