Abstract

This study aimsto compare the effects of the combination between the mineral N-P-K fertilization and the foliar sprayed chitosan (Chs), potassium-humate (K-H), and potassium-silicate (K-Si) on the nutrients uptake by the maize crop planted in sandy soil. The field experiments were carried at the Ismailia agricultural research station (2022 and 2023 summer seasons). The experiments were conducted in a split-split plot design with three replicates. The main plots were presented as follows; 50%, 75% and 100% of recommended N-P-K doses. While, sub plots were assigned for foliar sprayed (control (CL), Chs, K-H and K-Si). Results have indicated that the most significant increase in the grains yield was by 76.5% for the Chs at the 50% rate and by 56.7% and 48.8% for the K-Si at the 75%, and 100% N-P-K, respectively. The highest significant available N concentration was by 71.4%, 70.5% and 33.1 for the Chs, obtained at the 75%, 50%, and 100% N-P-K rates, respectively. The Chs has showed the highest concentration of the soil-available P by 69.5% and 59% at the 100% and 50% N-P-K rates, respectively. The available K (mg kg^-1) in soil was varied significantly. The sprayed K-Si was almost the most significant treatment has increased the uptake (kg ha^-1)of the N, P, and K in the ranges 69.9 – 202.6%, 12.6 – 109.1%, and 71 – 99.9%, respectively, within the 50% – 100% range of the N-P-K mineral fertilization.

Keywords

Chitosan; K-Humate; K-Silicate; Maize; Sandy Soil, Spray fertilization