## 1 Introduction  
Grapevine [_Vitis_ sp.] is a perennial woody fruit crop species with high economic and nutritional value [1]. Typical grapevine primary breeding objectives include greater yield and higher quality, tolerance to biotic and abiotic stresses, and desirable plant growth habits [1]. However, the heterozygosity and long generation cycle of _Vitis_ present a breeding challenge [1; 2; 3]. Molecular mapping with transferable markers provides the opportunity to reduce the time needed to study interspecific populations by facilitating quantitative trait loci (QTL) identification, marker assisted selection, and candidate gene discovery [1; 3; 4]. The results of QTL mapping vary among populations (size and genetic background) and marker type; therefore, the development of a genetic map with strong marker transferability is a timely requirement for grapevine breeding [4]. Restriction enzyme-based GBS methods strongly influenced genetic map construction over the past ten years and have several advantages such as, the possibility to apply to any species without prior genomic knowledge, simultaneous marker discovery and genotyping, low cost, high throughput, and scalability [5; 6; 7]. Limitations are that GBS marker development requires high-quality DNA to prevent heterozygous genotypes being wrongly called as homozygous (heterozygous under calling), generally targets gene-rich regions, and interspecific marker transferability can be as low as 2% [5; 6; 8]. In contrast, development of rhAmpSeq core genome markers needs diverse species genome sequences to target collinear regions with moderate polymorphism and produces fewer markers than GBS technology; however, these local haplotype markers are more informative and have high transferability across the _Vitis_ genus [8]. Grapevine breeding and trait mapping have proceeded rapidly with the availability of genome sequences, molecular marker implementation and evolution, and increased use of interspecific crosses for the introgression of economic traits [6]. Berry skin color, a qualitative trait, has been mapped to a major locus on chromosome 2 and associated with \(MYBA1\) gene [9; 10; 11; 4; 4; 12]. Anthocyanins (concentration and type) influence berry color and contribute to wine quality and have been mapped to chromosome 2, 7, 12, 13, and 14 [15; 16; 17]. Another qualitative trait, flower type, also maps to chromosome 2 [18; 19; 20; 21; 22; 23; 8]. Thus, berry color and flower type provide well studied reference points for validating and comparing genetic maps and genome-wide association studies in populations generated from _V. vinifera_ L., _V. rotundifolia_ Michx., and interspecific crosses [9; 10; 25]. Quantitative traits that are of high value for molecular assisted selection (disease resistance, agronomic traits, and berry chemistry) are rapidly being assessed to identify their relevant loci and candidate genes [11]. With many breeding programs focused on increased disease resistance, the introgression of non-vinifera species has also increased the emphasis on berry chemistry traits as non-vinifera species can contribute different fruit characters that may impact product quality. QTL analyses for standard fruit harvest parameters (berry acids, soluble solids, and pH) show multiple loci varying with population and year [26; 27; 28; 29; 30]. Fewer volatile QTL have been identified in berries, although many genes and enzymes associated with volatile development in berries have been detected [31]. The methoxypyrazines (3-isobutyl-2-methoxyprazine (IBMP), isopropyl methoxypyrazine (IPMP)) and C6 volatiles (hexanal, hexanal) are of particular interest as these herbaceous volatiles are found at high concentrations in wild _Vitis_ spp. and can contribute positive and negative odors depending on their concentrations [32; 33; 34; 35].