The effect of NPK foliar fertilization on yield and macronutrient content of grain in wheat under Kostanai-Kazakhstan conditions

Abstract

The objective of this research were to determine the effects of foliar fertilization (20% N:20% $P_2O_5$: 20% $K_2O$) at different growth stages on yield and nutrient contents of springwheat (Triticum aestivum L.) and to reveal proper application time and frequency inKostanai-Kazakhstan conditions. The field experiment was conducted according torandomized plot design with four replications with a seeding rate of 500 seed per m2 on theplots having a size of 5.0 m length and 4.0 m width. Foliar applications of the fertilizer at1%rate were done at tillering (T), stem elongation (S), heading (H) stages of wheat and thecombinations of these stages (T+S, T+H, S+H and T+S+H). Wheat yield values variedbetween the lowest 1.32 t/ha in the control and the highest 2.14 t/ha in the foliarfertilization done at tillering and steam elongation stages (T+S). According to controltreatment, increases in grain yields by the foliar fertilization done at the different growthstages were determined as follows; T+S (61.7%) > T+H (47.4%) > T+S+H (41.8%) > S+H(41.6%) > T (38.5%) > S (19.1%) > H (16.6%). There was no significant difference amongthe macronutrient contents in grain obtained by the foliar fertilization at the differentgrowth stages. N, P and K contents in the grain were close the values cited in the literatures.Ca and Mg contents deficiency in grain were determined due to the acidic soil pH conditionof Kostanai-Kazakhstan. Nitrogen, P, K and Ca uptakes by grain, except Mg, generallyincreased with the all application of foliar fertilization. When the foliar fertilization wasdone at T+S stages, the highest macro nutrient uptakes by grain in wheat were generallyobtained. This research indicated that the first foliar fertilization should be applied at thetillering stage and the best foliar fertilization management for high grain yield and nutrientuptake should be done two times at the combination of tillering and stem elongation stages.