Nanoformulations of Chitosan Alter Growth, Yield, and Metabolic Signatures in Tomato Plants
摘要
In agricultural soils in northern Mexico, such as those in the state of Coahuila, low fertility persists, a situation exacerbated by the excessive use of inorganic fertilizers, which compromises the productivity and quality of horticultural crops. In this context, the application of nanotechnology, through the use of organic chitosan-based nanofertilizers or nanobiostimulants, is emerging as an ecological and sustainable alternative for agriculture. This study individually evaluated the effect of two types of nanocomposites, chitosan-maltodextrin (Ch-Md) and chitosan-alginate (Ch-Alg), on growth, yield, fruit quality, and biochemical parameters in tomato plants (Solanum lycopersicum c.v. El Cid F1). The treatments were applied foliar at concentrations of 0.5, 1.5, and 2.5 mL L− 1 in addition to control without nanocomposites (Steiner nutrient solution). The nanocomposites of Ch-Alg at 0.5 and 1.25 mL L⁻¹ significantly increased plant height. In reproductive variables, Ch-Md at 2.5 mL L⁻¹ stood out by increasing the number of fruits and total yield per plant, surpassing the control. Furthermore, Ch-Alg at 1.25 mL L⁻¹ increased fruit firmness and total soluble solids compared to the control. At different concentrations, Ch-Alg recorded the highest values of phenols, amino acids, and glutathione. The higher antioxidant activity was observed with Ch-Md at 0.5 mL L⁻¹. The findings confirm the potential of maltodextrin- or alginate-functionalized nanocomposites as sustainable biostimulants to optimize tomato fruit yield and quality under greenhouse conditions. Despite these advances, uncertainties and questions remain regarding the physiological and genetic processes and mechanisms by which chitosan nanocomposites interact with plant cells, highlighting the need for research focused on the uptake and transport of nanoparticles and minerals, as well as enzymatic and gene expression.