Flavour improvement in early generations of fresh market tomatoes (Solanum lycopersicum L.): II. Response to breeders' sensory and marker-assisted selection

Abstract

Fresh market tomatoes are often characterized by poor flavour. Flavour is a quantitative trait difficult to assess and often neglected in breeding. Classical sensory methods are not suitable for the evaluation of early segregating generations; simple physicochemical measurements are not sufficient to predict perceived aroma. Alternative selection methods are needed, such as the recently introduced Breeders' Sensory Test or marker-assisted selection (MAS). Two unrelated crosses were chosen to evaluate the efficiency of phenotypic selection with the Breeders' Sensory Test (breeders' sensory selection, BS) and MAS for five quantitative trait loci for sweetness, sourness and tomato aroma (mapped in ‘Resi’ × ‘Auriga’) in organic low-input and hydroponic cultivation. Selection for sensory attributes reduced fruit weight, emphasizing the challenge of breeding flavourful, large-fruited tomatoes. Both selection methods were more effective in ‘Roterno F1‘× ‘Black Cherry’ derived from more distant parents. A trend towards higher efficiency of MAS in early segregating generations was observed for sweetness and tomato aroma. However, a major advantage of BS is its universal applicability. To improve flavour, combining both methods is recommended.