Effect of N Rate and Application on Spanish Peanut (Arachis hypogaea L.) Yield and Seed Grade, N and Oil.¹

Due to conflicting results of previous studies, experiments were conducted to study the effect of rate and time of application of N on the yield of fruit and on seed grade, percent N and oil content of Spanish peanuts (Arachis hypogaea L.). Rates and times of application of N had no significant effect on yield, grade or percent N in seed of Starr peanuts grown on three different soil types. Application of 134.4 kg of N/ha to Fuquay soil 6 weeks after planting decreased oil content in the seed. When the same rate of N was split into two applications (1/2 at planting and 1/2 at 6 weeks), the oil content was significantly higher than when all the N was applied 6 weeks after planting. On Tifton soil, split applications of N (1/2 at 6 weeks and 1/2 at 12 weeks) tend to reduce the oil content of seeds as the N rates increased. The 134.4 kg/ha rate of N applied by this method produced a significantly lower oil content than where all the N was applied at planting or 6 weeks after planting.