INTERCROPPED OR MIXED COVER CROPS AND THEIR EFFECTS ON DECOMPOSITION AND NUTRIENT CYCLING IN A NO-TILLAGE SYSTEM IN THE CERRADO

• Grant number: 24/00226-3
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: July 01, 2024
• End date: May 31, 2025
• Field of knowledge: Agronomical Sciences - Agronomy - Crop Science
• Principal Investigator: Angélica Cristina Fernandes Deus
• Grantee: Pietra Wendeborn Zinezi dos Reis
• Host Institution: Faculdade de Engenharia (FEIS). Universidade Estadual Paulista (UNESP). Campus de Ilha Solteira. Ilha Solteira , SP, Brazil

Abstract

The principle of conservation systems is to keep straw on the soil. However, in regions with a tropical climate, such as the Cerrado, plant residues decompose quickly, reducing their persistence on the soil. In this sense, it is important to study combinations of cover crops that provide quality, quantity and durability of the mulch. The aim of this study is to evaluate the effect of single, combined and mixed cover crops on straw production and persistence, nutrient cycling and soybean yields in a no-tillage system in Cerrado area. So, since 2023, an experiment has been carried out under field conditions in Selvíria/MS. The treatments are composed of 8 management of cover crops, single - Urochloa (Syn. Brachiaria), Black oats, Crotalaria and Buckwheat, consortium - Brachiaria + Crotalaria, Black oats + Buckwheat, Crotalaria + Buckwheat, Mix - Crotalaria + Black oats + Buckwheat, plus fallow, with no cover crop. Each treatment has four replications. The cover crops will be sown in May 2025 and desiccated in September, and soybeans will be sown in November 2025. The dry matter production and nutrient accumulation of the cover crops will be evaluated. The decomposition of plant residues and nutrient cycling will be analyzed at 30, 60, 90, 120, 150 and 180 days. Nutritional status, production components and grain yield will be used to assess the agronomic performance of the soybean crop. Basal soil respiration will be evaluated, which will provide information on the biological activity of the soil.