Effect of Different Levels of Nitrogen and Magnesium Fertilizers on Grain Yield and Its Components of Corn ( Zea mays L. ) in Calcareous Soil .

Abstract

A Field experiment was conducted during the season 2015 in Kirkuk province to study effect of different levels of Nitrogen and magnesium fertilizers on yield grain and its components of Corn crop in calcareous soil. using RCBD design with two factors. The first was Nitrogen fertilizer which was added at four levels (0, 240 ,280 ,320 Kg N.ha-1) as Urea, while the second factor was magnesium fertilizer was added at four levels (0, 80, 160,240 Kg Mg.ha-1) as magnesium sulphate (MgSO4.7H2O). Result indicated that the application of N and Mg fertilizer significantly increase grain yield and its components .. highest grain 5145.00 Kg . ha-1 at N2Mg2 treatment ( 280 kg N . ha-1 + 160 kg Mg . ha-1 ). Addition of Nitrogen fertilizer in presence of Mg fertilizer decrease fertilizer requirement of corn crop from (320) Kg N . ha-1 to (280) Kg N. ha-1 . The increase in grain yield was mainly due to the number of grain . cob-1 and secondly to 100 grain weight .