MAIZE RESPONSE TO ZINC APPLICATION UNDER DEFFERENT PHOSPHORUS FERTILIZATION LEVELS, ITS NUTRIENTS UBTAKE, AND AVAILABILTY IN ALLOUVIAL SOILS

Two field experiments were conducted during two successive seasons 2006 and 2007 at the experimental farm of Sakha Agric. Rec. Station, Kafer El- Sheikh Government. The aim of this study was to investigate the influence of zinc addition 0, 10, and 20 Kg/ fad. For Zn₀(S) (control), Zn₁₀(S), and Zn₂₀(S), respectively or foliar application with or without urea, 2% urea [U(F)], 500 ppm Zn [Zn (F)] and 2% urea + 500 ppm Zn [U+ Zn ( F)], respectively under different levels of phosphorus fertilization 30, 45, and 60 Kg p₂o₅ for P_1, P₂, and P₃ respectively on maize yield and its chemical composition. Ratherfore soil content of P , Zn , Fe, and Mn. The experiments were conducted in split plot design where P levels were the main plot and Zn treatments as were sub plot with four replicates.
The obtained results can be summarized as follows:

the yield and its components of maize were significantly affected by P and Zn fertilizer treatments.
Application of  P₃ increased grain yield by 12.0 and 12.5% and biomass by 17.6 and 13.8 compared to control treatment (P₁)in 2006 and 2007 seasons.
soil application of 10 Kg zn / fad. under P₃ level gave the highest value of grain yield in the two seasons. and of the biomass in the first season, meanwhile [U+ Zn(F)] treatment gave the highest  biomass value in the second season. While, the highest value of 1000 grain weight were obtained by [Zn₀ (s)] and [U+ Zn (F)] treatments in the two seasons.
the maximum values of P maize grain content were obtained by Zn₂₀(S) treatment under P₃ and P₂ in the two seasons respectively.
the maximum values of P maize stem content were obtained by [Zn₁₀(s )]and  [Zn (F)] treatments under P₂  in the two seasons , respectively.
the maximum values of  zn maize grain content were obtained by [U+ Zn (F)] treatment under P₂  level, while [Zn (F)] treatment gave the maximum maize stem zn content under P₃ level in the two seasons.
the maximum values of maize grain and stem Fe content were obtained by application of [U+ Zn(F)] treatment under P₁ level in the two seasons except grain in the first season. The same treatment also gave the maximum values of Mn of maize grain and stem under P₃  level except the stem in the first season.
Translocation coefficient (TC%) of heavy metal from stem to grain can be arranged in the following decreasing sequence  Zn > Mn> Fe.
Available P, Fe, and Mn increased by increasing P fertilizer levels from P₁ to P₃, while available Zn increased by increasing P fertilizer levels from P₁ to P₂ but at P₃ it decreased.
[U+ Zn (F)] treatment gave the highest available P, Fe, and Mn, while the highest available Zn was obtained by [Zn₂₀(s)] treatment.