Vehiculization of Atrazine in nanoparticulate systems for agricultural applications

AGUSTINA PRIETO ; GABRIELA CORDON; IVANA LÓPEZ VALIÑO ; VIRGINIA DIZ

Ciudad Autónoma de Buenos Aires

Simposio; Explorando las fronteras de la Química: desafíos para el Siglo XXI; 2019

Facultad de Ciencias Exactas y Naturales (UBA) y la Universidad Ben-Gurión del Néguev

Agriculture is vitally important worldwide as a primary provider of food, as well as one of the main engines of the economy of many countries. The use of agrochemicals occupies a key role in the maximization of agricultural production against innumerable challenges like weeds, phytopathogens, herbivory and abiotic stress. However, its indiscriminate use can contribute to environmental pollution, putting non-target organisms at risk. Nanoherbicides possess advantages over traditional commercial formulations since they slow down the release of the herbicide (minimizes losses and therefore contamination), maintain or even increase the activity of the herbicide against weeds while being less toxic to non-target organisms1. Polymeric nanoparticles could be suitable as nanotransporters of agrochemicals given their biocompatibility, biodegradability and low toxicity. The use of these guarantees a more efficient interaction of the molecule under study with the species of interest2.The principal objective of this work was to design, synthesize and characterize a nanoherbicide containing atrazine to prove their effectiveness in agricultural use. Nanoherbicide (NH) consists of atrazine active ingredient included in chitosan polymeric nanoparticles (NPs). The agricultural application effectiveness was proving through a bioassay with plants. Maize (non-target) and chicory plants (target) were sprayed with 1 ml of the corresponding solution (NPs or NH). A modulated fluorometer (PAR-FluorPen FP 100-MAX-LM) was utilized to measure the variable chlorophyll fluorescence (OJIP test) of the treated leaves in vivo at 24, 48 and 72 hours after applying the treatments.Several parameters, which provide information about health of plants, were calculated from the OJIP test: Fm/F0, Fv/F0, Fv/Fm, ABS/RC, TR0/RC, ET0/RC, Dl0/RC, among others. Chitosan NPs resulted innocuous for both type of plants, while the NH produced noxious effects only on chicory. Most of the parameters analyzed presented statistically significant differences in chicory, pointing out deleterious effects of NH on the target specie. In the case of maize, no significant differences were observed between plants treated with NPs and NH. The results of this work could confirm that the methodology used for the preparation of NPs and atrazine NH was adequate, SEM images confirmed this result.