The Effect K Fertilization, Zn Foliar application and gypsum Soil Content on nutrients by corn (Zea mays L.)

Field experiment was Conducted in season of 2019 year at the University of Tikrit/ college of Agriculture. In two location differ in their gypsum content (4.78% and 17.69%). RCBD design with three Factors (Four K rates 0.0 , 80 , 120 , 200 kg K.h -1 ). Two gypsum soil contents 4.78% and 14.61% , and three Zinc rates (0.0 , 1 , 2 kg Zn.h -1 ) were used. The following results were Found. Application of K fertilization increased the dry weight of corn where the percentage increase were 17.45% , 21.26% and 38.68% respectively as compared to control treatment. Soil with high gypsum decreased significantly the corn dry weight by 20.66%> The results al so showed that the foliar of Zn significantly increase the Dry weight of corn. The percentage increase were 6.73% and 13.67% for both Zn1 and Zn2 as compared to Zn0. Location I gave higher yield at the treatment K3Zn2 where its percentage increase was 89.40 as compared to the treatment K3Zn2 at location 2 which gave the lowest yield. K application showed significant increase in nutrients uptake in the green shoot of corn, where the % increase of N were (43.11% , 56.73% and 91.90%) while with P (48.49 , 125.81% and 189.0%) and for K (100.25% , 182% and 294%). For Zn the % increase in shoot dry weight were (38.81% , 52.51% and 93.09%) treatment. The higher gypsum content decreased the uptake of the N,P,K,Zn and % decreased were 30.01% , 69.35% , 47.53, and 29.92 % for N,P,K and Zn respectively. Zinc application showed Significant increased in nutrients uptake , where the % increase for N were (14.42% and 34.38%) for p (17.09% and 37.34%) for K (25.13% and 51.54%) and for Zn (26.85% and 49.75%) for Zn1 and Zn2 as compared to Zn0 treatment.