Biostimulatory Action of Arbuscular Mycorrhizal Fungi Enhances Productivity, Functional and Sensory Quality in ‘Piennolo del Vesuvio’ Cherry Tomato Landraces

Arbuscular mycorrhizal fungi (AMF) are a promising tool to improve plant nutrient use efficiency (NUE) and tolerance against abiotic stresses. Moreover, AMF can potentially increase plant productivity and reduce the negative externalities of the agricultural sector. Our study aimed to elucidate whether AMF (containing <i>Rhizoglomus irregulare</i> and <i>Funneliformis mosseae</i>) could positively affect not only tomato growth and productivity but also the nutritional and nutraceutical quality of yellow-pigmented type (‘Giagiù’) and red-pigmented type (‘Lucariello’) tomatoes (<i>Solanum lycopersicum</i> L.). These cherry tomatoes are landraces of the Protected Designation of Origin (PDO) ‘Pomodorino del Piennolo del Vesuvio’ (PPV), one of the most typical agricultural products of the Campania region (Southern Italy). AMF rose fruit yield by increasing the number of fruits per plant (+49% and +29% in ‘Giagiù’ and ‘Lucariello’, respectively) but not of the fruit mean mass. AMF increased lycopene (+40%), total ascorbic acid (TAA; +41%), alanine (+162%), gamma-Aminobutyric acid (GABA; +101%) and branched-chain amino acids (BCAAs; +53%) in ‘Lucariello’. In ‘Giagiù’, AMF increased calcium (+63%), zinc (+45%), ASP (+70%), GABA (+53%) and the essential amino acids arginine (+58%) and lysine (+45%), also indicating a genotype-specific response. In both landraces, AMF improved nutrient uptake and biosynthesis of important molecules involved in the control the oxidative stress and cellular pH. In addition to the beneficial effects of human health, the molecules influenced by the AMF treatment are expected to extend the shelf life of tomato fruits, thus further promoting the useful agronomic application of AMF for premium tomatoes marketed fresh or in pendulums (‘piennoli’).