Relationship between carryover and persistence of quinclorac in soils

• Grant number: 17/20497-8
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: January 01, 2018
• End date: March 02, 2019
• Field of knowledge: Agronomical Sciences - Agronomy - Plant Health
• Principal Investigator: Kassio Ferreira Mendes
• Grantee: Felipe Gimenes Alonso
• Host Institution: Centro de Energia Nuclear na Agricultura (CENA). Universidade de São Paulo (USP). Piracicaba , SP, Brazil
• Associated scholarship(s): 18/09345-4 - Sorption-desorption of glyphosate and its metabolite aminomethylphosphonic acid in floodplain soil, BE.EP.IC

Abstract

Residues of quinclorac herbicide cause phytotoxification to sensitive crops in rotation with rice, due to the high persistence of the product in the soil, a phenomenon known as carryover. There are no studies in the literature that relate quinclorac persistence and carryover to soil, which are essential properties to avoid phytotoxification in rotational crops. The objective of this research is to evaluate the relationship between the RL50 (half-life time in which 50% of the herbicide residue in the soil causes phytotoxification in a sensitive crop) and DT50 (half-life time in which 50% of amount herbicide applied initially in the soil is degraded) of carryover and the persistence, respectively, of quinclorac herbicide in five soils. Soil samples will be collected from cultivated areas in five different sites with contrasting texture. The experiments of persistence (degradation) will be carried out with 14C-quinclorac, being possible to quantify the bound residues, extractable residues (parent product and metabolites) and mineralized. A tomato bioindicator (Solanum lycopersicum), sensitive to quinclorac, will be used to evaluate the phytotoxification provided by the herbicide at 1, 30, 60, 90, 120, 180, 240 and 360 days after application. Pearson's correlation will be performed between the DT50 and the RL50. With the information generated in this research, it will be possible to predict the time required for the safe planting of a crop in succession, without carrying carryover with herbicide residues, and to know how much the DT50 matches the RL50. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

ALONSO, FELIPE GIMENES; MENDES, KASSIO FERREIRA; JUNQUEIRA, LEONARDO VILELA; TAKESHITA, VANESSA; ALMEIDA, CASSIO DE SOUZA; TORNISIELO, VALDEMAR LUIZ. Distribution and formation of degradation products of C-14-quinclorac in five tropical soils. ARCHIVES OF AGRONOMY AND SOIL SCIENCE, v. 66, n. 11, NOV 2019. (17/20497-8)