Construction of a high-density genetic map of Ziziphus jujuba Mill. using genotyping by sequencing technology

Abstract Pumpkin is a popular vegetable crop and exhibits a broad diversity in fruit shape and size. Fruit-related traits are the decisive factors determining consumer acceptance and market value of pumpkin cultivar. As a result, deciphering the genetic basis of fruit-related traits is of great importance for pumpkin breeding. To address this problem, a F2 population was generated by two Cucurbita moschata inbred lines with contrasting fruit shapes and genotyping-by-sequencing approach were used to construct a high-density genetic map and localize the QTLs underlying the fruit-related traits in this study. The results showed that a high-quality genetic map was constructed for pumpkin, which comprised of 2413 bins and spanned a total length of 2252.10 cM with an average genetic distance of 0.94 cM. A total of 30 significant QTLs with moderate or small effects were identified for 7 fruit-related traits, including fruit length, fruit diameter, fruit shape index, fruit weight, fruit flesh thickness, seed cavity size, and total soluble solids content. Co-locations and close locations were observed between the QTLs underlying different traits, demonstrating that pleiotropic effect plays an important role in genetic control of fruit-related traits. The identified QTLs provide valuable information for further fine mapping of the related genes and pumpkin breeding programs with the aim of improving fruit quality.

Download Full-text

A High-Density Genetic Map Enables Genome Synteny and QTL Mapping of Vegetative Growth and Leaf Traits in Gardenia

Frontiers in Genetics ◽

10.3389/fgene.2021.802738 ◽

2022 ◽

Vol 12 ◽

Author(s):

Yang Cui ◽

Baolian Fan ◽

Xu Xu ◽

Shasha Sheng ◽

Yuhui Xu ◽

...

Keyword(s):

Genetic Map ◽

Molecular Genetic ◽

Genetic Research ◽

Genotyping By Sequencing ◽

Leaf Traits ◽

Coffea Canephora ◽

High Density ◽

Specific Pcr ◽

True Hybrid ◽

Allele Specific

The gardenia is a traditional medicinal horticultural plant in China, but its molecular genetic research has been largely hysteretic. Here, we constructed an F1 population with 200 true hybrid individuals. Using the genotyping-by-sequencing method, a high-density sex-average genetic map was generated that contained 4,249 SNPs with a total length of 1956.28 cM and an average genetic distance of 0.46 cM. We developed 17 SNP-based Kompetitive Allele-Specific PCR markers and found that 15 SNPs were successfully genotyped, of which 13 single-nucleotide polymorphism genotypings of 96 F1 individuals showed genotypes consistent with GBS-mined genotypes. A genomic collinearity analysis between gardenia and the Rubiaceae species Coffea arabica, Coffea canephora and Ophiorrhiza pumila showed the relativity strong conservation of LG11 with NC_039,919.1, HG974438.1 and Bliw01000011.1, respectively. Lastly, a quantitative trait loci analysis at three phenotyping time points (2019, 2020, and 2021) yielded 18 QTLs for growth-related traits and 31 QTLs for leaf-related traits, of which qBSBN7-1, qCD8 and qLNP2-1 could be repeatably detected. Five QTL regions (qCD8 and qSBD8, qBSBN7 and qSI7, qCD4-1 and qLLLS4, qLNP10 and qSLWS10-2, qSBD10 and qLLLS10) with potential pleiotropic effects were also observed. This study provides novel insight into molecular genetic research and could be helpful for further gene cloning and marker-assisted selection for early growth and development traits in the gardenia.

Download Full-text