Effects of Nitrogen Fertilization on Yield and Quality of Different Peanut Cultivars

A pot experiment was conducted to investigate the effects of nitrogen fertilization on the yield and quality of three peanut cultivars. The results show that the highest pod yields of the Baisha1016 and Luhua12 cultivars are under the N 1125 kg/ha treatment, while the highest pod yield of Yuanza 9102 is under the N 75 kg/ha treatment. The contents of protein and amino acid in peanut seeds with N application are 4.9% and 15.0% higher than those without N application, respectively, and the contents of crude fat in seed are significantly increased by 3.7% at the N 375N 1125 levels. The contents of essential amino acids in peanut seed such as threonine, methionine, isoleucine, phenylalanine and lysine are increased significantly, and the unessential amino acids are also increased significantly except that of praline. The contents of stearic acid, arachic acid and behenic acid in peanut seed are increased varied among different peanut cultivars, and the N fertilization could improve the nutritional value of peanut seeds by 13.6%, 6.9% and 5.5%. There are significant differences in the seed protein and amino acid contents of the three peanut cultivars. The contents of the amino acid constituents are obviously different except threonine, tryptophan and glycin, while the content of the compositions of fatty acids are no obvious differences except margaric acid and stearic acid. In summary, then fertilization rates leading to the highest yield varied among different peanut cultivars. N fertilization could improve the nutritional value of peanut seeds.