Effect of Phosphorus and Nitrogen Application and Rhizobium Inoculation on Yield and Nutrient Uptake in Sainfoin (Onobrychis Sativa)

Abstract

An experiment was conducted during 2002 and 2003 to determine the effects of phosphorus and nitrogen application and Rhizobium inoculation on yield and nutrient uptake in 'Erzincan' sainfoin (Onobrychis sativa L.), grown in Van, Turkey. Successive increase in nitrogen dose (40 to 80 kg/ha) significantly increased the plant height (90.3 cm in 2002 and 90.8 cm in 2003), fresh forage (1.48 and 1.47 tonnes/ha in 2002 and 2003 respectively) and hay yields (0.60 tonne/ha in 2002 and 2003) in both the years. The highest values were obtained from the 80 kg N/ha and above 80 kg N/ha the values of these parameters decreased. However, nitrogen (5.14 in 2002 and 5.42% in 2003), phosphorus (0.260 and 0.263% in 2002 and 2003) and potassium (11.64 and 11.75% in 2002 and 2003) contents in plant increased with the increasing dose of nitrogen and found maximum at 120 kg N/ha. An application of 39 kg P/ha significantly increased the plant height (87.4 and 87.5 cm in 2002 and 2003), fresh forage (1.44 tonnes/ha and 1.43 tonnes/ha in 2002 and 2003) and hay yields (0.57 and 0.58 tonnes/ha in 2002 and 2003). Moreover, application of phosphor-us increased the nitrogen(4.49 and 4.58% in 2002 and 2003), phosphorus (0.259 and 0.262% in 2002 and 2003) and potassium (11.02 and 11.03% in 2002 and 2003) contents in plant. Rhizobium inoculation also significantly increased all the investigated parameters over the control. The highest yield (1.58 tonnes/ha fresh forage and 0.64 tonnes/ha hay in 2002, 1.59 tonnes/ha fresh forage and 0.64 tonnes/ha hay in 2003) were obtained from the application of 80 kg N/ha + 30 kg P/ha + Rhizobium inoculation. However, highest nutrient contents were obtained from the application of 120 kg N/ha + 39 kg P/ha + Rhizobium inoculation.