A strategy to develop prairie grapes (Vitis) with high trans-resveratrol production potential

Abstract

A strategy to develop Prairie grapes (Vitis) with high trans-resveratrol production potential is proposed. Young greenhouse grown vines were induced to flower through training and pruning and were screened for resveratrol in ripe berry skins. The fourteen genotypes were selected based on percentage of V. riparia Michaux in their pedigrees. Based on reported percentage of riparia (0, ~25, 50 and 100%), four groups of genotypes were selected that had at least three genotypes per group. It was hypothesised that accessions with a higher percentage of riparia would produce more resveratrol and that pedigree could be used to predict production potential. The 50% V. riparia group included two additional accessions that were anthocyanin-deficient clones of ‘Frontenac’. Resveratrol production in grape skins was elicited with UVC light (254 nm) placed above and below detached berries. Incubation-day five was chosen as the day of highest observed resveratrol concentrations. All Vitis vinifera Linnaeus cultivars tested on this day were lower producers of trans-resveratrol than V. riparia selections. Of the cultivars tested, V. riparia x F1 hybrid ‘Valiant’ was the highest producer with an average of approximately 693 µg g-1 fresh weight. Pure V. riparia selection ‘DG Riparia’ was similar to ‘Valiant’ in its resveratrol production potential. The ‘gris’ and ‘blanc’ anthocyanin-deficient mutants of ‘Frontenac’ have similar capacity to produce resveratrol as the original cultivar. In conclusion, resveratrol production potential cannot be predicted purely on % V. riparia in pedigree but it was generally true that hybrids based on this species were higher producers than classic V. vinifera cultivars. Genotypes ‘DG Riparia’ and ‘Valiant’ will be useful as parents in breeding Prairie-adapted grapes high in trans-resveratrol. Greenhouse culture offers an effective means of early selection for resveratrol production potential through flower induction pruning. This induction protocol will also be a useful tool in breeding grapes at the University of Saskatchewan.