Multiple Localization Analysis of the Major QTL—sfw 2.2 for Controlling Single Fruit Weight Traits in Melon Based on SLAF Sequencing
Author:
Cai Yi12, Wang Di3, Che Ye3, Wang Ling1, Zhang Fan1, Liu Tai3, Sheng Yunyan1
Affiliation:
1. Horticulture and Landscape Department, Heilongjiang Bayi Agriculture University, Daqing 163000, China 2. Horticultural Branch of Heilongjiang Academy of Agricultural Sciences, Harbin 150069, China 3. Daqing Branch of Heilongjiang Academy of Agricultural Sciences, Daqing 163000, China
Abstract
Cucumis melo is an annual dicotyledonous trailing herb. It is fruity, cool, and refreshing to eat and is widely loved by consumers worldwide. The single fruit weight is an important factor affecting the yield, and thus the income and economic benefits, of melon crops. In this study, to identify the main QTLs (quantitative trait locus) controlling the single fruit weight of melon and thereby identify candidate genes controlling this trait, specific-locus amplified fragment sequencing (SLAF) analysis was performed on the offspring of female 1244 plants crossed with male MS-5 plants. A total of 115 individual plants in the melon F2 population were analyzed to construct a genetic linkage map with a total map distance of 1383.88 cM by the group in the early stages of the project, which was divided into 12 linkage groups with a total of 10,596 SLAF markers spaced at an average genetic distance of 0.13 cM. A total of six QTLs controlling single fruit weight (sfw loci) were detected. Seven pairs of markers with polymorphisms were obtained by screening candidate intervals from the SLAF data. The primary QTL sfw2.2 was further studied in 300 F2:3 family lines grown in 2020 and 2021, respectively, a positioning sfw2.2 between the markers CY Indel 11 and CY Indel 16, between 18,568,142 and 18,704,724 on chromosome 2. This interval contained 136.58 kb and included three genes with functional annotations, MELO3C029673, MELO3C029669, and MELO3C029674. Gene expression information for different fruit development stages was obtained from 1244 and MS-5 fruits on the 15d, 25d, and 35d after pollination, and qRT-PCR (quantitative reverse transcription–PCR) indicated that the expression of the MELO3C029669 gene significantly differed between the parents during the three periods. The gene sequences between the parents of MELO3C029669 were analyzed and compared, a base mutation was found to occur in the intronic interval between the parents of the gene, from A-G. Phylogenetic evolutionary tree analysis revealed that the candidate gene MELO3C029669 is most closely related to Pisum sativum Fimbrin-5 variant 2 and most distantly related to Cucumis melo var. makuwa. Therefore, it was hypothesized that MELO3C029669 is the primary major locus controlling single fruit weight in melon. These results not only provide a theoretical basis for further studies to find genes with functions in melon single fruit weight but also lay the foundation for accelerating breakthroughs and innovations in melon breeding.
Funder
National Natural Science Foundation of China Natural Science Foundation of the Heilongjiang Province, China Programme of The Daqing Branch of Heilongjiang Academy of Agricultural Sciences
Reference60 articles.
1. Present and future of marker-assisted breeding in sweet and sour cherry;Campoy;Acta Hortic.,2019 2. Shi, P., Xu, Z., Zhang, S., Wang, X., Ma, X., Zheng, J., Xing, L., Zhang, D., Ma, J., and Han, M. (2020). Construction of a high-density SNP-based genetic map and identification of fruit-related QTLs and candidate genes in peach [Prunus persica (L.) Batsch]. BMC Plant Biol., 20. 3. Rapid and reliable identification of tomato fruit weight and locule number loci by QTL-seq;Huang;Theor. Appl. Genet.,2015 4. Curtolo, M., Cristofani-Yaly, M., Gazaffi, R., Takita, M.A., Figueira, A., and Machado, M.A. (2017). QTL mapping for fruit quality in Citrus using DArTseq markers. BMC Genom., 18. 5. Wang, H., Yan, A., Sun, L., Zhang, G., Wang, X., Ren, J., and Xu, H. (2020). Novel stable QTLs identification for berry quality traits based on high-density genetic linkage map construction in table grape. BMC Plant Biol., 20.
|
|