CAPS marker-base genetic linkage mapping and QTL analysis for watermelon ovary, fruit and seed-related traits

Primary mapping of quantitative trait loci regulating multivariate horticultural phenotypes of watermelon (Citrullus lanatus L.)

“…In this experiment, two extremely divergent watermelon parent lines (W1-38 and PI542119) were used for genomic sequencing and a total of 3,784,650 SNPs and 172,151 CAPS loci pairs were detected; however, transition type SNPs were noticed higher than transversion type SNPs. A total of 210 sets of novel SNP-CAPS markers exhibited a moderate level of polymorphism (46.25%), and the obtained results are fairly comparable with the earlier reported genetic mapping studies in watermelon (Liu et al, 2015;Liu et al, 2016;Amanullah et al, 2021;Osae et al, 2021;Amanullah et al, 2022;Osae et al, 2022). Our constructed genetic map had a total length of 2,398.40 cM, an average interval length of 11.42 cM, and most physical intervals ranging from a minimum of 680.12 kb to a maximum of 950.70 kb, indicating lower recombination rate (Figures 3, 4).…”

“…The detected positive and negative additive effects of our mapped QTLs exhibited the variation of multiple ovary characteristics (OWt, OL, OW, and OSI) in the developed F 2:3 mapping population and mainly signified the mutual genetic heredity of both parent lines. We also discovered that our mapped QTLs regions contradicted those previously mapped QTLs (Dou et al, 2018b;Legendre et al, 2020;Osae et al, 2022), as shown in Supplementary Table S9, respectively.…”

“…Watermelon genotypes have short and long ovaries with differentiated weight ( Weetman, 1937 ; Osae et al., 2022 ), and flowers of some botanical varieties are monoecious or andromonoecious ( Poole and Grimball, 1938 ; Aguado et al., 2020 ). The developed ovary and mature fruit display a high correlation since pre-anthesis.…”

“…Further, watermelon fruit-related quality traits are extremely connected with each other and significantly fascinate the consumer’s attention. Fruit weight varies from 1 kilogram (kg) to more than 10 kg and mainly depends upon the fruit size and shape, affecting the total crop yield ( Gusmini and Wehner, 2006 ; Osae et al., 2022 ). Fruit flesh firmness is a standard quantitative trait that determines the edible quality of watermelon, and variations are genetically inherited with genotypes and environments.…”

“…Whole genome sequencing approach coupled with the published de novo reference genome assembly of watermelon has assisted in developing the base-by-base SNP markers and high-resolution genetic linkage mapping ( Guo et al., 2013 ). In recent years, SNP based codominant CAPS markers have been emerged as an efficient DNA markers for dissecting the major-effect QTLs of regulating the important qualitative and quantitative traits of melon and watermelon ( Bang et al., 2007 ; Liu et al., 2015 ; Cheng et al., 2016 ; Liu et al., 2016 ; Li et al., 2017 ; Zhang et al., 2018 ; Liu et al., 2019 ; Luan et al., 2019 ; Wang et al., 2019 ; Sun et al., 2020 ; Amanullah et al., 2020 ; Amanullah et al., 2021 ; Zhang et al., 2021 ; Pei et al., 2021 ; Osae et al., 2021 ; Yang et al., 2021 ; Amanullah et al., 2022 ; Osae et al., 2022 ; Lv et al., 2022 ).…”