Search

[Display omitted] • The effects of a plant biostimulant (PB) on greenhouse cherry tomato were studied. • Analysis of two clusters (2nd vs. 6th) ripening during different periods. • Detailed profile of carotenoids and tocochromanols in tomatoes were reported. • The PB promoted yield and all lipophilic antioxidants but depressed sugars. • Stronger PB effects were noticed on 6th cluster (ripening in winter) A greenhouse experiment was conducted to study the effects of the application of a plant-derived biostimulant (Bioup® TF) on fruit quality and composition of two clusters (cluster II and cluster VI) of the cherry tomato cultivars 'Eletta', 'Kaucana', and 'Top Stellina'. The biostimulant application promoted fruit yield by 12% (up to 1.3 kg m−2 in 'Kaucana') and increased the concentrations of important functional constituents like phytoene, γ-tocopherol and β-tocopherol by up to 16, 25, and 23%, respectively. Fruits from late-ripe cluster VI showed higher fruit weights, D-fructose, and total sugar contents than those from early-ripe cluster II (by 15, 7 and 5%, respectively), but reduced concentrations of acyclic carotenoids (phytoene and lycopene) and tocochromanols (mainly γ-tocopherol, −44%). 'Top Stellina' showed the highest responsiveness to the biostimulant, as particularly (all- E)-β-carotene, phytofluene, and γ-tocopherol concentrations increased, indicating a genotype-dependent effect of the treatment. However, fruits of all treated genotypes showed a contextual decrease in D-fructose and total sugars in response to the biostimulant (on average by 7 and 10%, respectively), indicating a metabolic load burdening the accumulation of lipophilic antioxidants in cherry tomatoes at the expense of their taste-related C pool. [ABSTRACT FROM AUTHOR]

Over the last few decades, the improvement of tomato aroma and flavour has gained growing attention among breeders, agronomists and food technologists, as it is reputed as a key tool to further consolidate tomato consumption in the global market. However, this represents a difficult task, since more than 400 volatile organic compounds (VOCs) differently contribute to tomato aroma and its flavour perception. The recent development of molecular tools has allowed us to identify some of the major alleles influencing the volatile composition of tomatoes. Nonetheless, such composition involves an intricate weave of polygenic systems, highly influenced by external, pre and postharvest factors. With few exceptions, our knowledge about the effects of these determinants is still scarce, making it difficult to draw sound conclusions to best manage the future genetic potential. The present review examines the existing knowledge on major VOCs influencing tomato organoleptic quality, including their classification, metabolic pathways, genetics, and technical features that affect their concentrations in fruits. Particular emphasis is placed on preharvest and postharvest factors influencing their quantitative and qualitative expression, whose integrated study with omic tools will be increasingly necessary for the perspective of disseminating reliable operational indications throughout the production/distribution chain. [ABSTRACT FROM AUTHOR]

A greenhouse experiment was conducted to study the effects of the O2 root zone level and grafting on chlorophyll fluorescence, photosynthesis and growth of cherry tomato grown in a hydroponic system. Two O2 concentrations in the root zone, namely Ox (saturation level) and Ox- (2–3 mg L−1), were applied for 30 days on self-grafted cherry tomato Dreamer or grafted onto the hybrids Arnold, Beaufort, Maxifort and Top Pittam. Root hypoxia increased minimum fluorescence (by 10%) while it decreased variable fluorescence and the maximum quantum yield of PSII (up to 16 and 8%, respectively). Moreover, it reduced leaf photosynthesis, transpiration and stomatal conductance (by 12, 17 and 13%, respectively), whereas it increased leaf electrolyte leakage (by 2.1%). The graft combinations showed a different ability in buffering the effects of root hypoxia on plant growth and related components, and these differences were related to their root biomass. The minimum fluorescence was negatively correlated to plant growth, so it may be a useful indicator to select tolerant rootstocks to root hypoxia. Our results suggest the occurrence of both diffusive and metabolic constraints to tomato photosynthesis under root hypoxia, a condition that can be mitigated by selecting rootstocks with a more developed root system. [ABSTRACT FROM AUTHOR]