A non-destructive method to predict polyphenol content in strawberry

Fruit total phenolic content (TPC) and total antioxidant capacity (TAC) are usually assessed by destructive wet chemistry. Yet, for precision agriculture and recent breeding program, more rapid and non-destructive methods are needed. A new portable device, Dualex, is used to access the epidermal polyphenol content of leaves in order to select seedlings with good fruit quality. A field experiment was conducted to investigate the potential of Dualex, applied to fruit breeding, on four selected strawberry genotypes (‘Kent’, ‘Jewel’, ‘Saint-Pierre’ and ‘SJ8976-1’) of known quality. Our results showed that Dualex readings either from the adaxial side (upper side, DUAD), abaxial side (lower side, DUAB), sum of DUAD and DUAB (Phen), soluble solids content (SSC), titratable acidity (TA), TPC and TAC of ‘Jewel’ and ‘Kent’ were significantly higher than those of ‘SJ8976-1’ and ‘Saint-Pierre’. There were positive correlations between DUAD, DUAB and Phen vs. SSC, TA, TPC and TAC. The use of Dualex in strawberry breeding programs might be useful to estimate TA and SSC along with TPC and TAC to select for high fruit quality in a seedling population, which consequently reduces the time from crossing to naming and reduce field costs.