Accepted 11th October, 2014
The experiment was conducted from 2011 to 2012 for two years at Sinana on-station and on farms (Selka and Agarfa) with the objective to determine optimum seed rate and fertilizer level for herbage and grain production. The trial was carried out in factorial RCBD with three replications. Seed rates of 60, 70, 80 and 90 kg/ha were used as main plot treatments where as fertilizer rates of 0, 25kg UREA and 50 kg DAP, 50kg UREA and 100 kg DAP and 75kg UREA and 150 kg DAP were used as sub plot treatments. DM yield, seed yield, plant height and standing percentage and leaf to stem ration were significantly (P<0.05) varied among different seed rate and fertilizer rate combination. The DM yield of fodder oat increased with increasing level of fertilizer. The highest value (15.0 t/ha) was obtained at seed rate of 80kg/ha and at the higher fertilizer level. This could be due to the more competitiveness of oats with weeds at the higher seeding rate. Moreover, these fertilizers promote vigorous plant growth and a larger leaf area that contribute to the dry matter yield of the fodder oat. At the higher levels of fertilizer application, the DM contents did not increase significantly. It indicated that there is no significant difference in DM yield of fertilizer application of 50kg UREA and 100 kg DAP and the highest level which is 75kg UREA and 150 kg DAP. However, seeding rate and application of fertilizers above optimum level often produce no additional yield increase. Moreover, higher fertilizer rates could result in higher lodging of oats. Hence, there is no need to go for higher seed rate and fertilizer level. The highest seed yield (44.8Q/ha) was obtained at seed rate of 70kg/ha and fertilizer rate of 50kg UREA and 100 kg DAP, while the lowest seed yield 36.8Q/ha was obtained at seed rate of 80kg/ha without fertilizer. A modest increase in seed yield occurred with an increased seeding rate up to 70kg/ha with fertilizer level of 50kg UREA and 100 kg DAP. The increasing seeding rates above 70kg/ha are more likely to reduce size and quality of seed. The highest plant height (134.2cm) was recorded at the higher fertilizer level with seed rate of 80 and 90 kg/ha respectively. The lowest plant height (124.3 cm) was recorded at seed rate (80kg/ha) without fertilizer application. This study also indicated that application of fertilizer showed significantly (P<0.05) higher plant height than group having no fertilizer. Generally, the study indicated that seeding rates and fertilizer application at different level have an impact on yield and agronomic parameters of fodder oat. So it is found to be very important to have the optimum seed rate and fertilizer level for producing reasonable DM and seed yield of fodder oats. Hence, the optimum seed rate and fertilizer level to get reasonable DM yield will be at seed rate of 80 kg/ha and at fertilizer level of 50kg UREA and 100 kg DAP. While if the target is for forage seed production, seed rate of 70kg/ha with fertilizer rate of 50kg UREA and 100 kg DAP is very optimum to farmers in order to obtain reasonable yield.
Keywords: Fodder oats, Avena sativa, Bale highland