Assessment of the yield and yield attributing characters of oat (Avena sativa L.) grown under different tillage methods and NPK fertilizer rates in semi-arid conditions

Field experiments were conducted to determine the effect of tillage practices and inorganic sources of different combinations of nitrogen, phosphorus, and potassium fertilizers on some physical properties of soil and the yield of oats. The main plots were tillage techniques of no-till (T1), tillage with a cultivator (T2), twice-disc harrow (T3), and moldboard plowing (T4). Split-plots were fertilizer treatments of F1 control without fertilizer, 70:45:50 kg ha-1 NPK (F2), 140:90:100 kg ha-1 NPK (F3), 210:135:150 kg ha-1 NPK (F4), and 280:180:200 kg ha-1 NPK (F5). Soil density, acidity, electrical conductivity, and soil organic carbon increased under T1, while saturated hydraulic conductivity decreased compared with other tillage practices. Soil bulk density and pH increased with increasing sampling depth, while electrical conductivity and soil organic carbon declined with depth. Results from this study indicated a reduction in saturated hydraulic conductivity with time. The highest grain yield was found in the T4 and T3. In contrast, the highest grain yield was observed under F4 and F5 fertilization treatments at location 1 and F5 and F4 treatments at location 2. There were significant differences in growth characteristics and yield components due to the influence of tillage practices and fertilization levels in both experiment locations.