Fuente: ISHS (International Society for Horticultural Science) Post date: Saturday 31 May 2025
Author:
ISHS Secretariat

Research into the chemical and sensory nature of strawberry flavor has been conducted for over 50 years. However, until recently, there has been little integration of this flavor research into the breeding pipeline for commercial strawberry cultivars. Strawberry flavor is a complex, subjective trait that results from a combination of sugars, acids and volatile aroma compounds (VOCs). Sensory panel studies, combined with chemical analysis, have indicated that there is a small set of key aroma compounds responsible for the flavor and sweetness of strawberries. To facilitate the genetic improvement of strawberry flavor, two approaches are available: 1) genome-wide association (GWAS) and development of molecular markers for key aroma compounds, and 2) genomic prediction for breeder-based sensory evaluations. For this study, berries from 400 breeding lines in the University of Florida Strawberry Breeding Program were used for chemical analysis by GC-MS, which enabled quantification of key compounds including furaneol, mesifurane, γ-dodecalactone and γ-decalactone. PCR-based high resolution melting markers were based on GWAS results to screen for the increased production of furaneol and mesifurane, as well as γ-dodecalactone and γ-decalactone in strawberry seedlings. Using Agrobacterium-mediated transient RNAi and overexpression assays in detached strawberry fruits, an enoyl-CoA hydratase gene responsible for lactone biosynthesis was validated. Sensory evaluations were conducted by members of the breeding team on a weekly basis over two years to evaluate strawberries for flavor, sweetness and sourness using a 1-5 scale. A total of 5182 observations were recorded for 1066 genotypes across 17 weeks by multiple tasters following a sparse testing design. The effects of genotype, taster, week and error were modeled as random effects to correct for the highly unbalanced design. The genetic effect for each sensory attribute was used as the response variable for genomic prediction, which demonstrated moderate average predictive abilities of 0.35-0.36 in 80:20 cross validation. A useful genomic prediction model, built from breeder-based sensory evaluations, represents an important paradigm shift in genetic improvement for strawberry flavor, as its implementation allows for selection of seedlings and early-stage breeding material where consumer sensory studies are not feasible.
Mark Porter won the ISHS Young Minds Award for the best oral presentation at the X International Strawberry Symposium in China in March 2025.
Mark Porter, University of Florida, Gulf Coast Research & Education, 14625 County Road 672, Wimauma, FL 33598, USA, e-mail: markporter@ufl.edu
The article is available in Chronica HorticulturaeTags: strawberry flavorCategories: Young Minds Award Winners