Study and understanding of genetic and molecular mechanism of seasonel vs. continuous flowering in strawberry (Fragaria)

National audienc

Comparative quantitative trait locus (QTL) suggests polyploidization in Fragaria led to different genetic keys for recurrent flowering in Fragaria

National audienc

Genetic dissection of seasonal vs recurrent flowering for better management of the production of fruits in the cultivated strawberry

National audienc

Elucidating the origin and evolution of a complex polyploid genus (e.g.: Fragaria) by using low-copy nuclear genes in a phylogenetical study

International audienc

Metabolite Quantitative Trait Loci for flavonoids provide new insights into the genetic architecture of strawberry ( Fragaria x ananassa ) fruit quality

Abstract Flavonoids are products from specialized metabolism that contribute to fruit sensorial (colour) and nutritional (antioxidant properties) quality. Here, using a pseudo full-sibling F 1 progeny previously studied for fruit sensorial quality of cultivated strawberry ( Fragaria x ananassa ), we explored over two successive years the genetic architecture of flavonoid-related traits using LC-ESI-MS (13 compounds including anthocyanins, flavonols and flavan-3-ols) and colorimetric assays (anthocyanins, flavonoids, phenolics, FRAP and TEAC antioxidant capacity). Network correlation analysis highlighted the high connectivity of flavonoid compounds within each chemical class and low correlation with colorimetric traits except anthocyanins. Mapping onto the female and male linkage maps of 152 flavonoid metabolic QTLs (mQTLs) and of 26 colorimetric QTLs indicated co-localization on few linkage groups of major flavonoid- and taste-related QTLs previously uncovered. These results pave the way for the discovery of genetic variations underlying flavonoid mQTLs and for marker-assisted selection of strawberry varieties with improved sensorial and nutritional quality

The genetic architecture of fruit colour in strawberry ( Fragaria × ananassa ) uncovers the predominant contribution of the F. vesca subgenome to anthocyanins and reveals underlying genetic variations

Fruit colour, which is central to the sensorial and nutritional quality of the fruit, is a major breeding target in cultivated strawberry ( Fragaria × ananassa ). Red fruit colour is caused by the accumulation of anthocyanins, which are water-soluble flavonoids. Here, using pseudo F 1 progeny derived from the cv. ‘Capitola’ and the advanced line ‘CF1116’ and taking advantage of the available high density SNP array, we delineated fruit flavonoids mQTLs (13 compounds: anthocyanin, flavonols and flavan-3-ols) and colour-related QTLs (total anthocyanins and fruit colour) to narrow genomic regions corresponding to specific subgenomes of the cultivated strawberry. Findings showed that the overwhelming majority of the anthocyanin mQTLs and other colour-related QTLs are specific to F. vesca subgenome but that other subgenomes also contribute to colour variations. We then focused on two major homoeo-mQTLs for pelargonidin-3-glucoside (PgGs) localized on both male and female maps on linkage group LG3a ( F. vesca subgenome). Combined high-resolution mapping of PgGs mQTLs and colour QTLs, transcriptome analysis of selected progeny individuals and whole genome sequencing of the parents led to the identification of several INDELS in the cis -regulatory region of a MYB102-like ODORANT gene and of the deletion of a putative MADS box binding motif in the 5’UTR upstream region of an anthocyanidin reductase ( ANR) gene, which likely underlie significant colour variations in strawberry fruit. The implications of these findings are important for the functional analysis and genetic engineering of colour-related genes and for the breeding by Marker-Assisted-Selection of new strawberry varieties with improved colour and health-benefits