Effect of different incorporation depths of phosphate fertilization on the yield of dry matter and tillering of black oat (<em>Avena strigosa</em> Schreb)

Abstract

The experiment was carried out in a greenhouse at the Department of Agronomy of Universidade Estadual de Maringá - PR, in pots containing 6kg of soil, with the objective of studying the effect of different incorporation depths of phosphate fertilization on the yield of dry matter and tillering of black oat (Avena strigosa, Schreb). The experimental design was completely randomized with five replications, totaling 40 units. The following treatments were studied: fertilization corresponding to 100 and 200kg P₂O₅ ha^-1, no incorporated and incorporated, at 5, 10 and 15cm depth, being triple super phosphate the phosphorus source. Four 8-cm-high cuts of the aerial plant parts were performed intervals of 40, 54, 75 and 96 days after sowing when the tillering of ten plants per pot were counted. After the first and the third cuts the plants were fertilized using levels corresponding to 200 and 100kg urea–source nitrogen ha^-1, respectively. The data were submitted to variance, but no difference (p > 0.05) in dry matter yield was observed between the fertilizer doses. The fertilizer incorporation caused an increase (p < 0.05) in dry matter yield and tillering, but these variables were not affected (p > 0.05) by the different incorporation depths.