TY - JOUR
T1 - Sympatric speciation of wild emmer wheat driven by ecology and chromosomal rearrangements
AU - Wang, Hongwei
AU - Yin, Huayan
AU - Jiao, Chengzhi
AU - Fang, Xiaojian
AU - Wang, Guiping
AU - Li, Guangrong
AU - Ni, Fei
AU - Li, Penghuan
AU - Su, Peisen
AU - Ge, Wenyang
AU - Lyu, Zhongfan
AU - Xu, Shoushen
AU - Yang, Yanhong
AU - Hao, Yongchao
AU - Cheng, Xinxin
AU - Zhao, Jinxiao
AU - Liu, Cheng
AU - Xu, Fengfeng
AU - Ma, Xin
AU - Sun, Silong
AU - Zhao, Yan
AU - Bao, Yinguang
AU - Liu, Cheng
AU - Zhang, Jingjing
AU - Pavlicek, Tomas
AU - Li, Anfei
AU - Yang, Zujun
AU - Nevo, Eviatar
AU - Kong, Lingrang
N1 - Publisher Copyright:
© 2020 National Academy of Sciences. All rights reserved.
PY - 2020/3/17
Y1 - 2020/3/17
N2 - In plants, the mechanism for ecological sympatric speciation (SS) is little known. Here, after ruling out the possibility of secondary contact, we show that wild emmer wheat, at the microclimatically divergent microsite of “Evolution Canyon” (EC), Mt. Carmel, Israel, underwent triple SS. Initially, it split following a bottleneck of an ancestral population, and further diversified to three isolated populations driven by disruptive ecological selection. Remarkably, two postzygotically isolated populations (SFS1 and SFS2) sympatrically branched within an area less than 30 m at the tropical hot and dry savannoid south-facing slope (SFS). A series of homozygous chromosomal rearrangements in the SFS1 population caused hybrid sterility with the SFS2 population. We demonstrate that these two populations developed divergent adaptive mechanisms against severe abiotic stresses on the tropical SFS. The SFS2 population evolved very early flowering, while the SFS1 population alternatively evolved a direct tolerance to irradiance by improved ROS scavenging activity that potentially accounts for its evolutionary fate with unstable chromosome status. Moreover, a third prezygotically isolated sympatric population adapted on the abutting temperate, humid, cool, and forested north-facing slope (NFS), separated by 250 m from the SFS wild emmer wheat populations. The NFS population evolved multiple resistant loci to fungal diseases, including powdery mildew and stripe rust. Our study illustrates how plants sympatrically adapt and speciate under disruptive ecological selection of abiotic and biotic stresses.
AB - In plants, the mechanism for ecological sympatric speciation (SS) is little known. Here, after ruling out the possibility of secondary contact, we show that wild emmer wheat, at the microclimatically divergent microsite of “Evolution Canyon” (EC), Mt. Carmel, Israel, underwent triple SS. Initially, it split following a bottleneck of an ancestral population, and further diversified to three isolated populations driven by disruptive ecological selection. Remarkably, two postzygotically isolated populations (SFS1 and SFS2) sympatrically branched within an area less than 30 m at the tropical hot and dry savannoid south-facing slope (SFS). A series of homozygous chromosomal rearrangements in the SFS1 population caused hybrid sterility with the SFS2 population. We demonstrate that these two populations developed divergent adaptive mechanisms against severe abiotic stresses on the tropical SFS. The SFS2 population evolved very early flowering, while the SFS1 population alternatively evolved a direct tolerance to irradiance by improved ROS scavenging activity that potentially accounts for its evolutionary fate with unstable chromosome status. Moreover, a third prezygotically isolated sympatric population adapted on the abutting temperate, humid, cool, and forested north-facing slope (NFS), separated by 250 m from the SFS wild emmer wheat populations. The NFS population evolved multiple resistant loci to fungal diseases, including powdery mildew and stripe rust. Our study illustrates how plants sympatrically adapt and speciate under disruptive ecological selection of abiotic and biotic stresses.
KW - Abiotic stress
KW - Biotic stress
KW - Robertsonian translocation
KW - Sympatric speciation
KW - Wild emmer wheat
UR - http://www.scopus.com/inward/record.url?scp=85081732283&partnerID=8YFLogxK
U2 - 10.1073/pnas.1920415117
DO - 10.1073/pnas.1920415117
M3 - Article
C2 - 32123089
AN - SCOPUS:85081732283
SN - 0027-8424
VL - 117
SP - 5955
EP - 5963
JO - Proceedings of the National Academy of Sciences of the United States of America
JF - Proceedings of the National Academy of Sciences of the United States of America
IS - 11
ER -