EFFECT OF SUBSUPFICIAL IRRIGATION BLADES ON NUTRIENT EXTRACTION AND WATER PRODUCTION IN PASTA

Abstract

The imminent risk of water scarcity growing alarmingly in various regions of the world has encouraged the adoption of more efficient irrigation methods as well as strategic changes in irrigation management. Alternatively, subsurface drip irrigation and deficit irrigation can be highlighted. The objective of this work was to evaluate the productivity, water productivity, nutrient content and extraction in Brachiaria brizantha cv. Marandu, submitted to five soil water potentials: 0, 50, 75, 100 and 125% of potential crop evapotranspiration (ETc). The work was conducted in the experimental area of ​​the Federal University of Viçosa - Rio Paranaíba Campus, MG. A completely randomized design with four replicates was used and the means were compared by regression and the Tukey test at 5% probability. The results showed that the water deficit reduced up to 54% of productivity, but increased 27% of water use efficiency. The productivity of the 75% ETc blade was similar to full irrigation, which could be an alternative to sites with water restrictions. On the other hand, sub-surface irrigation slides did not influence the NPK content, however, they reduced the amount of nutrient extracted. There are strong correlations between the extraction of N, P and K in the aerial part of the plants and dry matter production.