Development of a high-density genetic linkage map and identification of quantitative trait loci (QTLs) associated with Botrytis cinerea resistance in strawberry (Fragaria x ananassa Duch.)

Over the centuries, strawberry fruit quality has greatly improved through various selection studies. The discovery of genes and genomic positions related to traits such as fruit quality and resistance to diseases and pests has been accelerated by new biotechnological methods. The objectives of this study are (i) to construct single nucleotide polymorphism (SNP) Fana array-based high-throughput genetic linkage groups for the 'Fortuna x Rubygem' F1 1 population, and (ii) to detect quantitative trait loci (QTL) regions associated with Botrytis cinerea resistance in leaf and fruit traits of strawberry. A total of 945 and 984 SNPs were mapped in the 'Fortuna' maternal and the 'Rubygem' paternal maps, respectively. The lengths of the linkage groups (LGs) and the average length of 'Fortuna' were calculated to be 1814 cM and 55.0 cM, respectively. The total length of 'Rubygem' was determined to be 2170 cM, with an average length of 65.7 cM. The average marker densities for the'Fortuna' and 'Rubygem' linkages per cM were recorded as 0.58 and 0.53 markers, respectively. The 'Fortuna' female produced a mean of 28.64 markers per LG, while the 'Rubygem' male linkage groups had approximately 30 markers per LG. Five significant QTLs associated with resistance to B. cinerea in the leaves were identified in both parents. QTLs associated with resistance in strawberry fruits were found within a total of three LGs in different positions. The compressive genetic linkage maps developed in 'Fortuna x Rubygem' population can be used in genetic and QTL studies for important agronomical traits. The identified QTLs associated with Botrytis cinerea resistance may be preferred for use in future strawberry breeding programs to carry out marker- assisted selection.