Doses de fósforo combinadas calcário e silicato de magnésio para a aveia branca

Abstract

The white oats (Avena sativa L.) is a plant belonging to the family Poaecea being the most cultivated winter cereals, because it has great importance and several functions in human food, animal and soil cover. Like other crops, it needs nutritional support and soil chemical aspects for its development. In this sense, the objective of this work was to evaluate five rates of phosphorus (0, 50, 100, 150 and 200 mg dm -3 ) combined with two soil correctives (magnesium silicate and limestone). The experimental design was a completely randomized factorial (DIC) with 10 treatments and 4 replications totaling 40 experimental units. The work was developed under controlled conditions of water replenishment (80% of the field capacity) in a greenhouse located on the campus of the Universidade Federal da Grande Dourados (UFGD). The agronomic and soil attributes were determined the nitrogen and phosphorus concentrations of the roots and aerial part, and the SPAD value. The values of pH, H+Al and Al +3 were better with the use of limestone. The levels of Al +3 and K in the soil decreased and the P content increased with the P rates. The number of tillers, plant height, root PMS, shoot PMS, number of panicles, length of panicles and number of spikeletsper panicle increased with rates of P. The number of tillers and number of panicles were higher when limestone was used. By the dilution effect the concentrations of nitrogen and phosphorus decreased with the rates of P, whereas the phosphorus concentration in the roots increased. The use of limestone as corrective soil acidity was improved by improving soil chemical attributes, which reflected the agronomic attributes. Taking into account the agronomic attributes, rates of P higher than 200 mg dm -3 are recommended.