Response of different strawberry genotypes to Mo-biofortification in a soilless system

Strawberry (Fragaria × ananassa Duch.) is a perennial plant belonging to the Rosaceae family. It is widely grown worldwide, and Sicily is the leading Italian region for early fruit production. Recent years have seen a large interest in several forms of human malnourishment, such as protein and calorie deficit; however, a major concern has focused on micronutrient deficiency. The agronomic biofortification technique represents an effective, viable, and profitable approach to alleviate micronutrient deficiency in humans. Among trace elements, molybdenum (Mo) is critical for plants, animals, and microbes. There is evidence that Mo can be satisfactorily included as a core micronutrient in agronomic biofortification programs. Mo-enzymes are involved in phytohormone biosynthesis, plant purine metabolism, sulfite detoxification, and nitrate absorption. Thus, Mo availability modulates plant growth and development, as well as yield. Furthermore, it is known that Mo participates in the chlorophyll biosynthesis pathway. However, Mo-enrichment efficiency is connected to Mo chemical form, type of application (foliar spray or fertigation), dose, and genotype. For the aforesaid premise, a trial was conducted in a greenhouse of the Department of Agricultural, Food, and Forestry Sciences of the University of Palermo, located in Marsala (Trapani Province) aiming to evaluate the effect of Mo doses (0, 0.5, 2 and 4 μmol L-1) on yield and fruit quality of three strawberry genotypes (‘Felicity’, ‘Palmeritas’ and ‘Florida Fortuna’). Strawberry plants were grown in an open cycle soilless system using coconut fiber/perlite (70/30, v/v) based substrate mix bags and Mo was supplied through the nutrient solution in the form of Na2MoO4. The results showed that all strawberry genotypes had an upsurge in the fruit Mo concentration in response to the biofortification treatments. Results showed that a dosage of up to 2 μmol L-1 had a beneficial effect on the yield of all genotypes. However, ‘Florida Fortuna’ yield decreased at 4 μmol L-1 Mo. The optimal doses to improve fruit quality features without jeopardizing yield were 4 μmol L-1 for ‘Felicity’ and ‘Palmeritas’ genotypes and 2 μmol L-1 for ‘Florida Fortuna’.