The objective of this work was to study the P and K fertilization effects on yield
components, yield and seed quality of Avena strigosa Schreber cv. Comum. The experiment was
carried out under field conditions on a Rhodic Nitisol (Terra Roxa Estruturada), in Botucatu, SP,
Brazil. Three dosis of P2O5 (0, 40 and 80kg/ha) and three dosis of K2O (0, 20 and 40kg/ha) were
studied as a factorial 3x3, in a randomized complete block design with four replications. Two
months before sowing, lime was applied at 2,5t/ha. All plots received 50kg/ha of N fertilizer,
parceled 20kg/ha at sowing and 30kg/ha at tillering stage. The fertilizers N-P-K sources employed
were ammonium sulphate, superphosphate and potassium chloride. The experiment was sowed in
04.23.97 and harvest in 09.04.97 (plots with P) and in 09.29.97 (plots without P). The phosphated
fertilization increased the panicle seed number of the main culm and of the tillers, the seed yield,
the dry weight of aerial part and the weight of 1000 seeds but did not affected germination, field
emergence and protein content of the seeds. The potassic fertilizantion gave rise to production of
seeds with high capacity of field emergence. The 40kg/ha of P2O5 dose and 20kg/ha of K2O dose
were sufficient to promote these favourable effects on yield and seed quality.