Population genetic structure and adaptive differentiation of iron walnut Juglans regia subsp. sigillata in southwestern China
Abstract Southwestern (SW) China is an area of active tectonism and erosion, yielding a dynamic, deeply eroded landscape that influences the genetic structure of the resident populations of plants and animals. Iron walnut (Juglans regia subsp. sigillata) is a deciduous tree species endemic to this r...
| Main Authors: | , , , , , , |
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| Format: | Article |
| Language: | English |
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Wiley
2019-12-01
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| Series: | Ecology and Evolution |
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| Online Access: | https://doi.org/10.1002/ece3.5850 |
| _version_ | 1818960394131079168 |
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| author | Yi‐Wei Sun Na Hou Keith Woeste Chuchu Zhang Ming Yue Xiao‐Ying Yuan Peng Zhao |
| author_facet | Yi‐Wei Sun Na Hou Keith Woeste Chuchu Zhang Ming Yue Xiao‐Ying Yuan Peng Zhao |
| author_sort | Yi‐Wei Sun |
| collection | DOAJ |
| description | Abstract Southwestern (SW) China is an area of active tectonism and erosion, yielding a dynamic, deeply eroded landscape that influences the genetic structure of the resident populations of plants and animals. Iron walnut (Juglans regia subsp. sigillata) is a deciduous tree species endemic to this region of China and cultivated there for its edible nuts. We sampled 36 iron walnut populations from locations throughout the species' range in SW China and genotyped a total of 765 individuals at five chloroplast DNA regions and 22 nuclear microsatellite loci. Species distribution models were produced to predict the evolution and historical biogeography of iron walnut and to estimate the impacts of climate oscillations and orographic environments on the species' demography. Our results indicated that J. regia subsp. sigillata had relatively low genetic diversity, high interpopulation genetic differentiation, and asymmetric interpopulation gene flow. Based on DIYABC analysis, we identified two lineages of J. sigillata in southwestern China. The lineages (subpopulations) diverge during the last glacial period (~1.34 Ma). Southwestern China was a glacial refuge during the last glacial period, but increasingly colder and arid climates might have fostered the fragmentation of J. regia subsp. sigillata within this refugium. Finally, we found that recent habitat fragmentation has led to a reduction in population connectivity and increased genetic differentiation by genetic drift in isolated populations. Our results support a conclusion that geological and climatic factors since the Miocene triggered the differentiation, evolutionary origin, and range shifts of J. sigillata in the studied region. |
| first_indexed | 2024-12-20T11:56:50Z |
| format | Article |
| id | doaj.art-f6e86e275bef4c9a878e929440fb3344 |
| institution | Directory Open Access Journal |
| issn | 2045-7758 |
| language | English |
| last_indexed | 2024-12-20T11:56:50Z |
| publishDate | 2019-12-01 |
| publisher | Wiley |
| record_format | Article |
| series | Ecology and Evolution |
| spelling | doaj.art-f6e86e275bef4c9a878e929440fb33442022-12-21T19:41:38ZengWileyEcology and Evolution2045-77582019-12-01924141541416610.1002/ece3.5850Population genetic structure and adaptive differentiation of iron walnut Juglans regia subsp. sigillata in southwestern ChinaYi‐Wei Sun0Na Hou1Keith Woeste2Chuchu Zhang3Ming Yue4Xiao‐Ying Yuan5Peng Zhao6Key Laboratory of Resource Biology and Biotechnology in Western China Ministry of Education College of Life Sciences Northwest University Xi'an ChinaGuizhou Academy of Forestry Guiyang ChinaDepartment of Forestry and Natural Resources USDA Forest Service Hardwood Tree Improvement and Regeneration Center (HTIRC) Purdue University West Lafayette IN USAKey Laboratory of Resource Biology and Biotechnology in Western China Ministry of Education College of Life Sciences Northwest University Xi'an ChinaKey Laboratory of Resource Biology and Biotechnology in Western China Ministry of Education College of Life Sciences Northwest University Xi'an ChinaKey Laboratory of Resource Biology and Biotechnology in Western China Ministry of Education College of Life Sciences Northwest University Xi'an ChinaKey Laboratory of Resource Biology and Biotechnology in Western China Ministry of Education College of Life Sciences Northwest University Xi'an ChinaAbstract Southwestern (SW) China is an area of active tectonism and erosion, yielding a dynamic, deeply eroded landscape that influences the genetic structure of the resident populations of plants and animals. Iron walnut (Juglans regia subsp. sigillata) is a deciduous tree species endemic to this region of China and cultivated there for its edible nuts. We sampled 36 iron walnut populations from locations throughout the species' range in SW China and genotyped a total of 765 individuals at five chloroplast DNA regions and 22 nuclear microsatellite loci. Species distribution models were produced to predict the evolution and historical biogeography of iron walnut and to estimate the impacts of climate oscillations and orographic environments on the species' demography. Our results indicated that J. regia subsp. sigillata had relatively low genetic diversity, high interpopulation genetic differentiation, and asymmetric interpopulation gene flow. Based on DIYABC analysis, we identified two lineages of J. sigillata in southwestern China. The lineages (subpopulations) diverge during the last glacial period (~1.34 Ma). Southwestern China was a glacial refuge during the last glacial period, but increasingly colder and arid climates might have fostered the fragmentation of J. regia subsp. sigillata within this refugium. Finally, we found that recent habitat fragmentation has led to a reduction in population connectivity and increased genetic differentiation by genetic drift in isolated populations. Our results support a conclusion that geological and climatic factors since the Miocene triggered the differentiation, evolutionary origin, and range shifts of J. sigillata in the studied region.https://doi.org/10.1002/ece3.5850evolutionary historygene flowgenetic differentiationgenetic structureJuglans sigillataSouthwest China |
| spellingShingle | Yi‐Wei Sun Na Hou Keith Woeste Chuchu Zhang Ming Yue Xiao‐Ying Yuan Peng Zhao Population genetic structure and adaptive differentiation of iron walnut Juglans regia subsp. sigillata in southwestern China Ecology and Evolution evolutionary history gene flow genetic differentiation genetic structure Juglans sigillata Southwest China |
| title | Population genetic structure and adaptive differentiation of iron walnut Juglans regia subsp. sigillata in southwestern China |
| title_full | Population genetic structure and adaptive differentiation of iron walnut Juglans regia subsp. sigillata in southwestern China |
| title_fullStr | Population genetic structure and adaptive differentiation of iron walnut Juglans regia subsp. sigillata in southwestern China |
| title_full_unstemmed | Population genetic structure and adaptive differentiation of iron walnut Juglans regia subsp. sigillata in southwestern China |
| title_short | Population genetic structure and adaptive differentiation of iron walnut Juglans regia subsp. sigillata in southwestern China |
| title_sort | population genetic structure and adaptive differentiation of iron walnut juglans regia subsp sigillata in southwestern china |
| topic | evolutionary history gene flow genetic differentiation genetic structure Juglans sigillata Southwest China |
| url | https://doi.org/10.1002/ece3.5850 |
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