Effects of different nitrogen doses and harvesting times on the forage yield and quality of oat

This study was conducted to determine the effects of different nitrogen doses and harvesting times on the forage yield and quality of oat (Avena sativa L.) at the Isparta University of Applied Sciences, Education, Faculty of Agriculture, Research, and Application Farm during 2024. The Seydişehir variety was used in the study. For nitrogen five different doses i.e. (0, 5, 10, 15 and 20 kg N da-1) while the harvesting times viz. (Heading, flowering and milk formation) were studied. The experiment was conducted with fifteen treaments in a split-plot design with three replications, within randomized complete block design. The experiment block area were 20 m2. To examine forage yield and quality in the study different agronomic parameters of oat i.e. (Plant height cm, green herbage yield kg/da, hay yield kg/da, crude protein %, crude protein yield kg/da, NDF ratio %, ADF ratio %, TSBM ratio % and NBD ratio % were recorded. According to the results, oat plant height 65.44-81.97 cm, green herbage yield 1557.7-2351.0 kg/da, hay yield 498.2-868.2 kg/da, crude protein ratio 6.90-9.43%, crude protein yield 41.20-74.04 kg/da, NDF ratio 59.08-64.95%, ADF ratio 37.81-48.58%, TSBM ratio 38.64-52.54% and NBD ratio 73.11-93.70% were noted. Increasing nitrogen doses plant height, green herbage yield, hay yield, crude protein ratio, crude protein yield and TSBM ratios increased while ADF ratio decreased. As the harvesting time passed plant height, green herbage yield, hay yield, crude protein yield, NDF and ADF ratios increased, while crude protein ratio, TSBM and NYD ratios decreased. Evaluatıng all the results obtained from the study, it was observed that applying nitrogen 20 kg/da and harvesting at milk formation stage gives the best results for higher fodder yield of oat while according to fodder quality of oat crop nitrogen application 15-20 kg/da and harvesting at heading and flowering stages gave better results. For higher yield and quality, nitrogen application 15 kg/da and harvesting at flowering stage is recommended. It is seen that for high yield and quality, it is better to apply at least 15 kg/da nitrogen application and harvesting at flowering stage.