Comparison of the Peel-Associated Epiphytic Bacteria of Anthocyanin-Rich “Sun Black” and Wild-Type Tomatoes under Organic and Conventional Farming

Abstract

Tomatoes are among the most consumed vegetables worldwide and represent a source of health-beneficial substances. Our study represents the first investigating the peel-associated epiphytic bacteria of red and purple (anthocyanin-rich) tomatoes subjected to organic and conventional farming systems. Proteobacteria was the dominant phylum (relative abundances 79–91%) in all experimental conditions. Enterobacteriaceae represented a large fraction (39.3–47.5%) of the communities, with Buttiauxella and Atlantibacter as the most represented genera. The core microbiota was composed of 59 operational taxonomic units (OTUs), including the majority of the most abundant ones. The occurrence of the most abundant OTUs differed among the experimental conditions. OTU 1 (Buttiauxella), OTU 2 (Enterobacteriales), and OTU 6 (Bacillales) were higher in red and purple tomatoes grown under organic farming. OTU 5 (Acinetobacter) had the highest abundance in red tomatoes subjected to organic farming. OTU 3 (Atlantibacter) was among the major OTUs in red tomatoes under both farming conditions. OTU 7 (Clavibacter) and OTU 8 (Enterobacteriaceae) had abundances ≥1% only in red tomatoes grown under conventional farming. PCA and clustering analysis highlighted a high similarity between the bacterial communities of red and purple tomatoes grown under organic farming. Furthermore, the bacterial communities of purple tomatoes grown under organic farming showed the lowest diversity and evenness. This work paves the way to understand the role of nutritional superior tomato genotypes, combined with organic farming, to modulate the presence of beneficial/harmful bacteria and supply healthier foods within a sustainable agriculture.

Tomato Plant Microbiota under Conventional and Organic Fertilization Regimes in a Soilless Culture System

“…Herein, it was shown that conventional and organic plants have comparable bacterial abundance and richness in substrate, rhizosphere, and fruit samples; however, it was revealed that organic plants endured microbiota dysbiosis characterized by an increase in the relative abundance and dominance of some specific bacterial groups. Comparable phenomena have been reported in other studies with tomato, lettuce, and teak plants [ 67 , 96 , 97 ].…”

“…Our data revealed that tomato core microbiota was dominated by phyla Proteobacteria, Actinobacteria, and Firmicutes in the substrate, rhizosphere, and fruit samples; comparable bacterial diversity has been reported in numerous studies with tomato plants cultivated in soil-based and SCSs [20,27,[63][64][65][66][67][68][69][70]. Together, these findings suggest that, regardless of the cultivation system, tomato plants have evolved a close biological interaction with members of Proteobacteria, Actinobacteria, and Firmicutes.…”

PGPB and/or AM Fungi Consortia Affect Tomato Native Rhizosphere Microbiota

“…Besides the importance in the overall vegetable crop cultivation, tomatoes also have a central function in the human diet. They are rich in antioxidants [ 4 ] with beneficial properties from anticancer and immune boosting responses to bowel disease amelioration [ 1 ]. Considering the constant intensification of agricultural practices and artificial selection, tomato plants are more susceptible to soil borne diseases due to their genetic homogeneity [ 5 , 6 ], and the adverse effects caused by climate change are adding more threats to the tomato yields [ 3 , 7 ].…”

Treatment of High-Polyphenol-Content Waters Using Biotechnological Approaches: The Latest Update

“…On the other hand, their activity in vivo depends on the bioavailability, the structures of compounds, and the composition and metabolic features of the human gut microbiota. In addition to antioxidant capacity, polyphenols have potential healthy properties for humans as anti-inflammatory, antiallergic, antihypertensive, neuropreventive, analgesic, antiviral, and antimicrobial agents [16,18,19]. These compounds are employed as effective antimicrobial agents in healthcare as an alternative to other treatments and in food preservation [20,21].…”