Effects of Arbuscular Mycorrhization on Fruit Quality in Industrialized Tomato Production

Abstract

Industrialized tomato production faces a decrease in flavors and nutritional value due to conventional breeding. Moreover, tomato production heavily relies on nitrogen and phosphate fertilization. Phosphate uptake and improvement of fruit quality by arbuscular mycorrhizal (AM) fungi are well-studied. We addressed the question of whether commercially used tomato cultivars grown in a hydroponic system can be mycorrhizal, leading to improved fruit quality. Tomato plants inoculated with Rhizophagus irregularis were grown under different phosphate concentrations and in substrates used in industrial tomato production. Changes in fruit gene expression and metabolite levels were checked by RNAseq and metabolite determination, respectively. The tests revealed that reduction of phosphate to 80% and use of mixed substrate allow AM establishment without affecting yield. By comparing green fruits from non-mycorrhizal and mycorrhizal plants, differentially expressed genes (DEGs) were found to possibly be involved in processes regulating fruit maturation and nutrition. Red fruits from mycorrhizal plants showed a trend of higher BRIX values and increased levels of carotenoids in comparison to those from non-mycorrhizal plants. Free amino acids exhibited up to four times higher levels in red fruits due to AM, showing the potential of mycorrhization to increase the nutritional value of tomatoes in industrialized production.

Caracterización de frutos tomate (Solanum lycopersicum) en plantas colonizadas por el hongo micorrízico arbuscular Rhizopagus irregularis en condiciones de estrés salino

“…Varios estudios han demostrado que la inoculación con estos hongos mejora el crecimiento de las plantas bajo estrés salino y aumenta la calidad de los nutrientes (Schubert et al, 2020;Tian et al, 2004). Esto puede ser atribuido al incremento en la adquisición de nutrientes minerales como fósforo (P), zinc (Zn), cobre (Cu) y hierro (Fe).…”

“…La variación en las poblaciones de estos hongos y su simbiosis con las raíces está relacionada tanto con las propiedades del suelo como con las plantas. En las últimas décadas, se ha obtenido una mayor conciencia de los efectos positivos de dicha simbiosis en el rendimiento de las plantas (Schubert et al, 2020). Además, las especies y los aislados de HMA difieren en su tolerancia a las condiciones físicas y químicas adversas del suelo (Aliasgharzad et al, 2017).…”

“…Los HMA son biomejoradores importantes para suelos salinos, ya que la colonización micorrízica arbuscular mejora el crecimiento, nutrición y vigor de la planta y mitiga el daño en las plantas hospederas causado por la salinización del suelo (Evelin et al, 2012). Además, existe evidencia de que la interacción de las plantas de tomate con los HMA aumenta la calidad de los nutrientes al aumentar los contenidos de ácido cítrico, carotenoides y ciertos aminoácidos, así como la capacidad antioxidante de los frutos (Schubert et al, 2020).…”

Strategies to Modulate Specialized Metabolism in Mediterranean Crops: From Molecular Aspects to Field

“…In the last ten years, several research groups focused the attention to evaluate the impact of AMF on the SM production in different horticultural crop species as well as in aromatic and medicinal plants. Although a positive impact on both yield and quality has been found [ 56 , 57 , 58 ], this is not always reported [ 59 ], probably depending on the genotypes and the cultivation conditions. In this paragraph, some examples of these researches have been reported, with the aim to underline the importance of the AM symbiosis in the cultivation of these plant species.…”

“…A significant increase in lycopene, total ascorbic acid (TAA), alanine, gamma-aminobutyric acid (GABA) and branched-chain amino acids (BCAA) has been in fact found in “Lucariello” local variety, as well as an increase in calcium, zinc, ASP, GABA and the essential amino acids arginine and lysine in “Giagiù” genotype. Schubert et al [ 59 ] focused instead on fruit gene expression and metabolite levels in industrialized tomatoes whose production faces a decrease in flavors and nutritional value due to conventional breeding. It is worth noting that red fruits from mycorrhizal plants showed an increased level of carotenoids in comparison to those from non-mycorrhizal plants, although an effect on yield was not observed.…”