Multiple species of wild tree peonies gave rise to the 'king of flowers', Paeonia suffruticosa Andrews.
The origin of cultivated tree peonies, known as the 'king of flowers' in China for more than 1000 years, has attracted considerable interest, but remained unsolved. Here, we conducted phylogenetic analyses of explicitly sampled traditional cultivars of tree peonies and all wild species from the shrubby section Moutan of the genus Paeonia based on sequences of 14 fast-evolved chloroplast regions and 25 presumably single-copy nuclear markers identified from RNA-seq data. The phylogeny of the wild species inferred from the nuclear markers was fully resolved and largely congruent with morphology and classification. The incongruence between the nuclear and chloroplast trees suggested that there had been gene flow between the wild species. The comparison of nuclear and chloroplast phylogenies including cultivars showed that the cultivated tree peonies originated from homoploid hybridization among five wild species. Since the origin, thousands of cultivated varieties have spread worldwide, whereas four parental species are currently endangered or on the verge of extinction. The documentation of extensive homoploid hybridization involved in tree peony domestication provides new insights into the mechanisms underlying the origins of garden ornamentals and the way of preserving natural genetic resources through domestication.
State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, The Chinese Academy of Sciences, Beijing 100093, People's Republic of China.
Shi-Liang
SL
Zhou
State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, The Chinese Academy of Sciences, Beijing 100093, People's Republic of China.
Xin-Hui
XH
Zou
School of Horticulture, Southwest University, Chongqing 400716, People's Republic of China.
Zhi-Qin
ZQ
Zhou
State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, The Chinese Academy of Sciences, Beijing 100093, People's Republic of China.
Jing
J
Liu
State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, The Chinese Academy of Sciences, Beijing 100093, People's Republic of China.
Chao
C
Xu
State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, The Chinese Academy of Sciences, Beijing 100093, People's Republic of China.
Jing
J
Yu
State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, The Chinese Academy of Sciences, Beijing 100093, People's Republic of China.
Qiang
Q
Wang
State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, The Chinese Academy of Sciences, Beijing 100093, People's Republic of China.
Da-Ming
DM
Zhang
State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, The Chinese Academy of Sciences, Beijing 100093, People's Republic of China.
Xiao-Quan
XQ
Wang
State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, The Chinese Academy of Sciences, Beijing 100093, People's Republic of China.
Song
S
Ge
State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, The Chinese Academy of Sciences, Beijing 100093, People's Republic of China.
Tao
T
Sang
State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, The Chinese Academy of Sciences, Beijing 100093, People's Republic of China.
Kai-Yu
KY
Pan
State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, The Chinese Academy of Sciences, Beijing 100093, People's Republic of China hongdy@ibcas.ac.cn.
De-Yuan
DY
Hong
D001483:Base Sequence; D005075:Biological Evolution; D061125:Genes, Chloroplast; D049810:Genetic Speciation; D008969:Molecular Sequence Data; D029596:Paeonia / Q000235:genetics* / Q000502:physiology; D010802:Phylogeny; D016415:Sequence Alignment
Paeonia; RNA-seq; conservation; hybridization; species tree