Dataset Information

Diversification and independent domestication of Asian and European pears.

ABSTRACT:

Background

Pear (Pyrus) is a globally grown fruit, with thousands of cultivars in five domesticated species and dozens of wild species. However, little is known about the evolutionary history of these pear species and what has contributed to the distinct phenotypic traits between Asian pears and European pears.

Results

We report the genome resequencing of 113 pear accessions from worldwide collections, representing both cultivated and wild pear species. Based on 18,302,883 identified SNPs, we conduct phylogenetics, population structure, gene flow, and selective sweep analyses. Furthermore, we propose a model for the divergence, dissemination, and independent domestication of Asian and European pears in which pear, after originating in southwest China and then being disseminated throughout central Asia, has eventually spread to western Asia, and then on to Europe. We find evidence for rapid evolution and balancing selection for S-RNase genes that have contributed to the maintenance of self-incompatibility, thus promoting outcrossing and accounting for pear genome diversity across the Eurasian continent. In addition, separate selective sweep signatures between Asian pears and European pears, combined with co-localized QTLs and differentially expressed genes, underline distinct phenotypic fruit traits, including flesh texture, sugar, acidity, aroma, and stone cells.

Conclusions

This study provides further clarification of the evolutionary history of pear along with independent domestication of Asian and European pears. Furthermore, it provides substantive and valuable genomic resources that will significantly advance pear improvement and molecular breeding efforts.

SUBMITTER: Wu J

PROVIDER: S-EPMC5996476 | biostudies-literature | 2018 Jun

REPOSITORIES: biostudies-literature

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Publications

Diversification and independent domestication of Asian and European pears.

Wu Jun J Wang Yingtao Y Xu Jiabao J Korban Schuyler S SS Fei Zhangjun Z Tao Shutian S Ming Ray R Tai Shuaishuai S Khan Awais M AM Postman Joseph D JD Gu Chao C Yin Hao H Zheng Danman D Qi Kaijie K Li Yong Y Wang Runze R Deng Cecilia H CH Kumar Satish S Chagné David D Li Xiaolong X Wu Juyou J Huang Xiaosan X Zhang Huping H Xie Zhihua Z Li Xiao X Zhang Mingyue M Li Yanhong Y Yue Zhen Z Fang Xiaodong X Li Jiaming J Li Leiting L Jin Cong C Qin Mengfan M Zhang Jiaying J Wu Xiao X Ke Yaqi Y Wang Jian J Yang Huanmimg H Zhang Shaoling S

Genome biology 20180611 1

<h4>Background</h4>Pear (Pyrus) is a globally grown fruit, with thousands of cultivars in five domesticated species and dozens of wild species. However, little is known about the evolutionary history of these pear species and what has contributed to the distinct phenotypic traits between Asian pears and European pears.<h4>Results</h4>We report the genome resequencing of 113 pear accessions from worldwide collections, representing both cultivated and wild pear species. Based on 18,302,883 identif ...[more]

PMID: 29890997

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Dataset Information

Diversification and independent domestication of Asian and European pears.

Background

Results

Conclusions

Publications

Diversification and independent domestication of Asian and European pears.

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