Effects of chitosan nanoparticles on growth, development, and nutraceutical quality of tomato (Solanum lycopersicum L.)

The tomato (Solanum lycopersicum L.), considered one of the most desirable horticultural crops in the world for its nutritional and nutraceutical qualities, is also used as a model for many studies. The objective of this research was to compare different concentrations of chitosan nanoparticles (NPs) on the growth and development of tomato plants, as well as on fruit quality. Three concentrations of chitosan and a control were applied to tomato leaves in a randomized block design with three replicates and four treatments. Different growth variables (plant height, stem diameter, root length and fresh and dry biomass of different plant organs) as well as fruit yield and polar and equatorial diameter were evaluated. Fruit quality was evaluated by determining the contents of total soluble solids (TSS, %), vitamin C (mg in 100 g), polyphenols (mg gallic acid per g), antioxidant capacity (µmol Trolox per g), flavonoids (mg catechin per g) and carotenoids (µg β-carotene per g). The positive effect of foliar applications of chitosan nanoparticles was proven. The higher concentrations favoured yield and fruit quality, increasing yield and contents in the different quality variables, while the medium concentration stimulated growth in general.