Tropical Grasses-Annual Crop Intercropping and Adequate Nitrogen Supply Increases Soil Microbial Carbon and Nitrogen

Author(s)

Batista, Karina ; Vilela, Laize Aparecida Ferreira

• Document type: Journal article
• Source: AGRONOMY-BASEL; v. 13, n. 5, p. 17-pg., 2023-04-28.

Abstract

In Brazil, grain crops in no-till soybean-maize succession have reduced biodiversity and carbon input into soil. Intercropping is a promising approach to address these problems. This study aimed to evaluate the microbiological quality of soil in conventional and intercropping systems in soybean-maize succession, depending on tropical grass and nitrogen fertilizer uses. The treatments were arranged in a randomized complete block design and a split plot scheme, with four replications. The main plots consisted of the following cropping systems: soybean monoculture-maize monoculture; soybean intercropped with Aruana Guinea grass (Megathyrsus maximum cv. Aruana)-maize intercropped with Aruana Guinea grass; and soybean intercropped with Congo grass (Urochloa ruziziensis cv. Comun)-maize intercropped with Congo grass. The subplots consisted of nitrogen rates (0, 50, 100, and 150 kg ha(-1)) applied as side-dressing in rows of maize and tropical grass in the autumn-winter season. Our results showed that maize or soybean intercropped with tropical grasses and adequate nitrogen rates favored the entry of microbial carbon and nitrogen, stimulated enzymatic activity, and reduced C-CO2 loss. However, the excess nitrogen supply can nullify the benefits of the intercropping systems. We concluded that the intercropping systems can improve soil microbiological quality in a short time with adequate nitrogen supply. (AU)

• FAPESP's process: 19/02387-6 - Forage plants and nitrogen in the succession soybean - out-of-season corn for the development of sustainable food systems
• Grantee: Karina Batista
• Support Opportunities: Regular Research Grants
• FAPESP's process: 17/50339-5 - Institutional research development plan of the Animal Science Institute (PDIp)
• Grantee: Lenira El Faro Zadra
• Support Opportunities: Research Grants - State Research Institutes Modernization Program