Organic residues as materials reducing the impact of preemergent herbicides on soil microbial activity

• Grant number: 22/12619-4
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: December 01, 2022
• End date: July 31, 2025
• Field of knowledge: Agronomical Sciences - Agronomy - Crop Science
• Principal Investigator: Valdemar Luiz Tornisielo
• Grantee: Ana Laura Camachos de Oliveira
• Host Institution: Centro de Energia Nuclear na Agricultura (CENA). Universidade de São Paulo (USP). Piracicaba , SP, Brazil
• Associated scholarship(s): 24/06220-7 - Indaziflam and simazine degradation under electricity fluxes applied in soil for weed control, BE.EP.IC

Abstract

Pre-emergent herbicides are applied targeted to the soil. The processes of retention, transport and degradation regulate the availability of these molecules in the environment. Microorganisms are responsible for processes essential for crop establishment, such as the decomposition of organic matter, biological nitrogen fixation, and nutrient cycling. They are also the main agents of herbicide degradation in the soil. Herbicide application can negatively affect soil microbial activity, causing toxicity and selection of the microbiota in the area. Organic residues present benefits for the soil microbiota and can reduce the availability of herbicides in the soil, maintaining the sustainability of the cropping system. Thus, this project aims to evaluate the effect of pre-emergent herbicides on soil microbial activity as a function of the addition and incubation of organic residues. Studies of respirometry using 14C-glucose according to the OECD (2002) will be conducted in an entirely randomized, factorial design. The variables are the herbicides (quincloraq, diuron, diclosulam and saflufenacil) and the soil (soil, soil+bonechar, soil+chicken manure, soil+spread), and the controls, evaluated in eight incubation times of the soil+waste, with three repetitions. The experimental units will be Bartha flasks and the amount of 14C-glucose mineralized will be calculated in relation to the initial amount applied. The glucose will be applied right after the herbicide application. Three aliquots will be collected from each flask, at the times 0.5, 1, 2, 4 and 8 h after the glucose application. The variable analyzed will be the mineralization of 14C-glucose as a function of time in each treatment. The results will allow the construction of glucose half-life curves for each treatment and determine the effect of herbicides and organic materials on soil microbial activity. With this project, we hope to contribute to the scientific community in the area of herbicide behavior in the environment, pointing out the effect of these products on the soil microbiota, as well as selecting organic residues capable of reducing the negative effects of herbicides on the soil. Pointing to management practices with the increase of organic matter in maintaining the sustainability of the cropping system.

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)

MUNHOZ-GARCIA, GUSTAVO VINICIOS; TAKESHITA, VANESSA; DE OLIVEIRA, JHONES LUIZ; DALLA VECCHIA, BRUNO; NALIN, DANIEL; PINACIO, CAMILA DE WERK; DE OLIVEIRA, ANA LAURA CAMACHOS; CARDOSO, BRIAN CINTRA; TORNISIELO, VALDEMAR LUIZ; FRACETO, LEONARDO FERNANDES. Nanobased Natural Polymers as a Carrier System for Glyphosate: An Interesting Approach Aimed at Sustainable Agriculture. Journal of Agricultural and Food Chemistry, v. 73, n. 2, p. 15-pg., 2025-01-02. (23/16519-7, 22/16554-4, 22/01554-9, 22/00718-8, 19/27255-5, 21/03455-5, 21/10639-5, 19/04758-1, 22/12619-4)

MUNHOZ-GARCIA, GUSTAVO VINICIOS; TAKESHITA, VANESSA; PINACIO, CAMILA DE WERK; CARDOSO, BRIAN CINTRA; DALLA VECCHIA, BRUNO; NALIN, DANIEL; DE OLIVEIRA, ANA LAURA CAMACHOS; FELIX, LEANDRO FERNANDO; TORNISIELO, VALDEMAR LUIZ. Radiometric approaches with carbon-14-labeled molecules for determining herbicide fate in plant systems. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY, v. 284, p. 14-pg., 2024-09-07. (19/04758-1, 21/03455-5, 22/01554-9, 22/16554-4, 22/00718-8, 22/12619-4)