*4.1. Genetic Map Constructed of Pepper*

*Phytophthora* blight caused by *P. capsici* is one of the most serious diseases in pepper, inducing a significant reduction in yield and quality [49]. Despite decades of genetic research on the resistance of pepper to *P. capsici*, no resistant cultivars have been established to date. At present, as a key tool, genetic linkage maps are not only used in plant genetics, but also to identify genomic regions that are related to agronomic and qualitative traits through QTL mapping. Recently, SLAF-seq has been utilized in the creation of genetic linkage maps of pepper, and a number of high-density genetic maps have been successfully created. For instance, Zhu et al. (2019) identified six QTLs using a molecular genetic linkage map via SLAF-seq in relation to flowering time and number of flowers per node in pepper, which consisted of a total of 9038 markers at an average spacing of 0.18 cm that were distributed across 12 linkage groups, and the total distance was 1586.78 cM [44]. In the same year, Zhang et al. (2019) identified two major pepper QTLs (*Ffn2.1* and *Ffn2.2*) that were strongly correlated with FFN using a high-density genetic map, which included 9328 SLAF markers from 12 linkage groups, showing a total genetic distance of 2009.69 cM, as well as an average distance of 0.22 cM [40]. Sun et al. (2020) reported two QTLs that were related to aphid survival (*Rmpas-1*) and reproduction (*Rmprp-1*) using a genetic linkage map that included 167 SNP markers [50]. In this work, we constructed a genetic map using the SLAF-seq technology and according to a F2 population. The map consisted of 5565 markers that assigned 12 linkage groups, spanning a total length of 1535.69 cM, and showed a mean genetic distance of 0.28 cM. This genetic map exhibited adequate coverage of the polymorphic markers in regions of interest, and the mapped QTLs showed positional accuracy.
