The State of Parana is the biggest brazilian producer of white oat (Avena sativa L.)
grains, with significant increase in the harvest area each year. The study was achieved in Londrina,
State of Parana, where the assay were developed in laboratory and field. The objective was to
evaluat the effect of the seed treatment and sowing depth, in the seedling emergence plant
development, in the microorganisms population of the rizhosphere and rizoplane of the planting
area of plants and production of oat grains. Seeds of white oat, cultivar OR-11, were sown in the
depths of 3cm, 5cm and 8cm. It were used fungicides in dosages of g.i.a./100kg of seed,
carboxim+thiram (93.7g+93.7g), thiram (210g) and triadimenol (50g) and the bilogical product
kodiak C (Bacillus subtilis) (60g). The treatment with the fungicides and the biological product
eliminated the fungi presents on the seeds, such as: Fusarium avenae, Colletotrichum graminicola
and Helminthosporium avenae and improve the plant development and the soil microorganisms,
being this variable with the sowing depth and the treatment.