Scientific Area
Abstract Detail
Nº613/680 - Whole genome sequencing deciphering nonbifurcating diversification of Camellia (Theaceae)
Format: ORAL
Authors
Qiong Zhang1, Ryan A. Folk2, Jian-Li Zhao3, Shi-Xiong Yang1, Xiang-Qin Yu1,*
Affiliations
1 CAS Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, China;
2 Department of Biological Sciences, Mississippi State University, MS 39762, United States;
3 Yunnan Key Laboratory of Plant Reproductive Adaptation and Evolutionary Ecology and Institute of Biodiversity, School of Ecology and Environmental Science, Yunnan University, Kunming 650091, China
* Correspondence: yuxiangqin@mail.kib.ac.cn
Abstract
Although increasing evidence suggested that introgression and reticulation might have affected almost all parts of the tree of life, published examples likely represent the tip of the iceberg in terms of the total extent of the ancient hybridization. Camellia, the largest genus with significant economic value of Theaceae, has controversial taxonomy and systematics due in part to a complex evolutionary history. Here, we sampled 64 species representing 20 out of 22 sections of Camellia according to Changs system. Integrating a group of data sets such as single copy nuclear genes, single-nucleotide polymorphism (SNP) and plastid coding genes extracted from whole genome resequencing data to investigate the patterns of reticulate evolution of Camellia. Camellia was divided into eight major clades (C1-C8). Our results yielded much phylogenetic incongruence among topologies reconstructed by three datasets (single copy nuclear genes, SNP, plastid genes) based on different methods (concatenation and coalescent), especially the cyto-nuclear discordance was observed. But all of them support non-monophyletic of sections proposed based on morphological characters. The splits phylogenetic network reconstructed by 508 single copy nuclear genes and ABBA-BABA test conducted by SNP data all support the introgression events in Camellia. Four groups based on the minimum CV error value were recovered in Admixture analysis, hybridization events are concentrated on Group II (C2-C6) and Group IV (C8). Although hybridization/introgression have some impacts on the reconstruction of the phylogenetic relationships of Camellia, no consistent topologies were detected after removing the putative introgressed loci in SNP. Our study laid a foundation for future researches of Camellia, such as plant taxonomy, evolutionary genomics, population genomics, and also provided a theoretical basis for the utilization and protection of important wild plant germplasm resources of the family.