Manejo de adubação fosfatada e micronutrientes na cultura do arroz de terras altas

Abstract

The cultivation of rice (Oryza sativa L.) has become an element of food security, as it has an important influence on the economic and social scenario. It is a precursor culture in the colonization and initiation of agricultural exploration in the Cerrado, this region being characterized by the vast planted area of rice in the highland system. The Cerrado soil has low levels of micronutrients, such as Molybdenum and Nickel. In addition, there is a shortage of phosphorus in the soil, which is the most limiting nutrient in the productivity in the Cerrado. Therefore, the objective was to evaluate the responses of upland rice culture to the management of phosphate fertilization and micronutrients, in Cerrado soil. The experiment was conducted in a greenhouse, the design used was completely randomized, with five replications. In the treatments, 3 sources containing Mo, Ni and NPK plus micronutrients (in two different concentrations) were used. Vegetative and reproductive characteristics were analyzed, such as: relative chlorophyll content, number of tillers, enzymatic activity (nitrate reductase and urea), porometer, fluorometer and productivity. The treatments did not obtain significant differences for the porometer index, both enzymatic activities, relative content of chlorophyll, tillering of plants and for the productivity of rice. In the fluorometer index, TestMoNi obtained higher values of this index, indicating a possible intact photosynthetic device.