ABSTRACT
Plants are capable of absorbing nutrients through aerial plant parts, so foliar application can be an effective method of applying fertilizer nutrients to plants under some conditions. Foliar application of the major fertilizer elements — N, P, K and S — has not been practiced extensively for grain crops because of the limitations due to the amounts required and the amounts that can be applied per application. Since a primary objective of foliar fertilization during seed-filling is to provide nutrients to the developing seeds, the rate of application required is related to the amounts of nutrients in the fully developed seeds. The research that has been conducted on foliar fertilization provides leads concerning the forms and amounts of the different nutrients that can and should be applied and the times and methods of application. During the seed-filling period in grain crops, soluble carbohydrates and several nutrient elements are translocated from the leaves and other vegetative plant parts to the developing seeds.
