Anticipation of nitrogen fertilization in the cultivation of upland rice and its effect on N availability and forms in soil

• Grant number: 18/23625-0
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: February 01, 2019
• End date: January 31, 2020
• Field of knowledge: Agronomical Sciences - Agronomy - Crop Science
• Principal Investigator: Carlos Alexandre Costa Crusciol
• Grantee: Fábio Nogueira da Silva
• Host Institution: Faculdade de Ciências Agronômicas (FCA). Universidade Estadual Paulista (UNESP). Campus de Botucatu. Botucatu , SP, Brazil

Abstract

Rice is one of the main cereals consumed in the world, and in this scenario upland cultivation has been highlighted by the low demand of water resources for its production. Because these are less productive cultivars, cost reduction is necessary for producers to remain competitive in the market. For this, the trend has been to optimize the operations in the crop field, being a possibility the anticipation of the nitrogen fertilization in the coverage plant or the straw in pre-planting. Therefore, the present work will evaluate the technical feasibility of the early application of nitrogen fertilizer to upland rice cultivation under no - tillage in succession to forage grasses. The experimental design was a randomized complete block design with four replications and treatments arranged in a 4 x 2 factorial scheme, with four treatments of nitrogen fertilization (without addition of nitrogen (0 kg ha-1) (T), with conventional nitrogen fertilization (A), with nitrogen fertilization anticipated in forage 10 to 5 days before desiccation (A1) and with early nitrogen fertilization in the forage straw already dried 5 to 1 day before sowing of rice (A2)) and two forages ( areas previously occupied by Urochloa brizantha cv. Marandu or Urochloa ruziziensis). In the treatments, except for the control (T), 30 kg ha-1 at sowing and 90 kg ha-1 will be applied in the respective treatments. In this sense, the project will evaluate 1) the productive performance and the biometric characteristics of upland rice, 2) the production, persistence and release of nitrogen from the straw of the forages U. brizantha and U. ruziziensis, 3) the changes in total nitrogen, nitrate and ammonium content of the soil throughout the crop cycle.