Potential use of preplant soil mineral nitrogen content in first crop corn fertilization programe in Çukurova region

In this research, potential usage of pre plant soil mineral nitrogen ?(N?_(min?)) in the first crop corn fertilization programme was studied in the Cukurova region. Corn, as a regional crop, provides a significant contribution to agricultural economy. The soil samples were taken at the pre plant and post harvest periods from three different depths (0-30, 30-60 and 60-90 cm) in 2007, 2008, 2009 years and ?NH?_4^+ and ?NO?_3^- concentrations were measured, and total N_min values were calculated. In addition, some parameters (shoot yield, grain yield, %N in shoot and grain, N uptake of shoot, grain and total plant) were measured and calculated to correlate with the soil values. This study was shown that, pre plant N_min level could contribute to corn production, and the farmers should consider this existing readily available nitrogen source in the profile. A significant amount of N_min was also determined in the soil profile at the post harvest stage, showing that farmers? fertilizer application are more than the plant needs. When soil and plant parameters were evaluated together, there were significantly important linear relationships. The research results showed that, the soil mineral nitrogen is an important factor that can be used in corn fertilization programe. However, there were no significant correlation was found between corn yield and the soil N_min values.