Preparation and characterization of lignin-based formulations for controlled release applications in agriculture

MARÍA EUGENIA TAVERNA; CRISTINA ZALAZAR; MAIA LESCANO; DIANA ESTENOZ; CARLOS BUSATTO; VERÓNICA NICOLAU

Mar del Plata

Simposio; XVI Latin-American Polymer Symposium (SLAP 2018); 2018

Instituto de Ciencia y Tecnología en Materiales (INTEMA)

Pesticides are important chemicals used in agriculture. However, some of these compounds exhibit persistence and mobility in the environment. Atrazine is a moderately toxic triazine, used as a selective pre- and post-emergence herbicide in various crops. The actual concern about the impact of agrochemicals on the environment has increased the use of natural pesticides instead of synthetic ones. Among these compounds, azadirachtin, a strong insect antifeedant and growth-regulating substance is widely used for pest control purposes. The use of azadirachtin-based pesticides may be limited by its susceptibility to photodegradation. The toxicity of atrazine and the photodegradation of azadirachtin can be reduced using polymer controlled release formulations that also increase the effectiveness of pesticides. In addition, natural polymers are of great interest for controlled release applications in agriculture due to their biodegradability, free availability, cost-effectiveness and low toxicity. Lignins are aromatic biopolymers from biomass, the second more abundant after cellulose.The aim of this work is to prepare lignin microparticles and alginate-lignin beads for the encapsulation and controlled release of atrazine and azadirachtin, respectively. The formulations are characterized in terms of particle size and morphology, encapsulation efficiency and controlled release behaviour in water.