Footprints of domestication revealed by RAD-tag resequencing in loquat: SNP data reveals a non-significant domestication bottleneck and a single domestication event

Yunsheng Wang, Muhammad Qasim Shahid, Shunquan Lin, Chengjie Chen, Chen Hu

The process of crop domestication has long been a major area of research to gain insights into the history of human civilization and to understand the process of evolution. Loquat (Eriobotrya japonica Lindl.) is one of the typical subtropical fruit trees, which was domesticated in China at least 2000 years ago. In the present study, we re-sequenced the genome of nine wild loquat accessions collected from wide geographical range and 10 representative cultivated loquat cultivars by using RAD-tag tacit to exploit the molecular footprints of domestication. We obtained 26.4 Gb clean sequencing data from 19 loquat accessions, with an average of 32.64 M reads per genotype. We identified more than 80,000 SNPs distributed throughout the loquat genome. The SNP density and numbers were slightly higher in the wild loquat populations than that in the cultivated populations. All cultivars were clustered together by structure, phylogenetic and PCA analyses. The modern loquat cultivars have experienced a non-significant genetic bottleneck during domestication, and originated from a single domesticated event. Moreover, our study revealed that Hubei province of China is probably the origin center of cultivated loquat.