Abstract

Sugar content is an important component of fruit quality. Although sugar transporters are known to be crucial for sugar accumulation, the role of genes encoding SWEET sugar transporters in fruit sugar accumulation remains elusive. Here we report the effect of the SWEET genes on fruit sugar accumulation in apple. A total of 25 MdSWEET genes were identified in the apple genome, and 9 were highly expressed throughout fruit development. Molecular markers of these 9 MdSWEET genes were developed and used for genotyping of 188 apple cultivars. The association of polymorphic MdSWEET genes with soluble sugar content in mature fruit was analyzed. Three genes, MdSWEET2e, MdSWEET9b, and MdSWEET15a, were significantly associated with fruit sugar content, with MdSWEET15a and MdSWEET9b accounting for a relatively large proportion of phenotypic variation in sugar content. Moreover, both MdSWEET9b and MdSWEET15a are located on chromosomal regions harboring QTLs for sugar content. Hence, MdSWEET9b and MdSWEET15a are likely candidates regulating fruit sugar accumulation in apple. Our study not only presents an efficient way of implementing gene functional study but also provides molecular tools for genetic improvement of fruit quality in apple-breeding programs.

Details

Title
Developing gene-tagged molecular markers for evaluation of genetic association of apple SWEET genes with fruit sugar accumulation
Author
Zhen, Qiaoling 1 ; Fang, Ting 1 ; Peng, Qian 1 ; Liao, Liao 2 ; Zhao, Li 2 ; Owiti, Albert 1 ; Han, Yuepeng 3 

 Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden of the Chinese Academy of Sciences, Wuhan, China; Graduate University of Chinese Academy of Sciences, Beijing, China 
 Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden of the Chinese Academy of Sciences, Wuhan, China 
 Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden of the Chinese Academy of Sciences, Wuhan, China; Sino-African Joint Research Center, Chinese Academy of Sciences, Wuhan, China; College of Horticulture Science and Engineering, Shandong Agricultural University, Tai-An, Shandong, China 
Pages
1-12
Publication year
2018
Publication date
Mar 2018
Publisher
Oxford University Press
e-ISSN
20527276
Source type
Scholarly Journal
Language of publication
English
ProQuest document ID
2015393489
Copyright
© 2018. This work is published under http://creativecommons.org/licenses/by/4.0/ (the “License”). Notwithstanding the ProQuest Terms and Conditions, you may use this content in accordance with the terms of the License.