Növénytermelés / Volume 62 / Issue 1 (March 2013) / pp. 37-51
Kremper R; Zsigrai Gy; Loch J
The effects of foliar zinc application on the yield and nutrient content of maize (Zea mays L.)
The effect of foliar zinc fertilization was studied at the 18–43 variant of the National Long Term Fertilisation Experiment of Karcag Research Institute in Hungary, the test plant was maize. The soil of the experiment site is non calcareous Luvic Phaeosem and its soluble phosphorus and zinc content are AL-P2O5: 323.0 mg kg-1 and KCl-EDTA Zn: 1.3 mg kg-1 respectively. Plots supplied with 200 kg ha-1 P2O5 were chosen for our experiments, because at these plots there is a real danger of phosphorus induced zinc deficiency. This decision is confirmed by our observation that at plots treated with this P dosage maize plants have typical Zn deficiency symptoms at 4–10th leaf stage of maturity.
The effect of foliar zinc fertilization was studied by three levels of nitrogen (150, 200, 250 kg ha-1) and under 200 kg ha-1 P2O5 and 100 kg ha-1 K2O application in four replication. A row of maize was sprayed in each plot with a suspension fertilizer containing zinc as zinc-oxide, zinc sulphate and another row in each plots was chosen as control treatment. The applied Zn amount was 700 g ha-1.
Leaf samples were collected from the maize at early silk, leaves under the ears were collected, and the phosphorus, zinc, potassium, calcium, magnesium and manganese content were determined by them. Beyond it we measured the kernel yield weight, the thousand kernel weight, the number of fertile ears and the nutrient content of the yield.
In the light of the results of variance analysis we concluded that foliar zinc application did not increase the yield significantly, but it enhanced the thousand kernel weight. The element content did not change significantly neither in the leaves nor in kernels as a result of zinc application. Based on these results it can be stated that under the examined habitat circumstances even the application of 200 kg P2O5 ha-1 phosphorus dosage does not cause Zn deficiency to such an extent which leads significant yield depression of maize. We stated that deficiency symptoms appearing in young plants cease at later maturity stages and it can be explained by the fact that when the active root system reaches the soil zone under the large phosphate activity zone, the soil can already provide the appropriate Zn amount that is necessary for plant growth.
Higher nitrogen doses increased both the yield and the number of fertile ears. They increased manganese content of the leaves also. There were not any significant change in case of zinc, phosphorus, potassium and magnesium content in the leaves samples. In the kernels only zinc, phosphorus, potassium and magnesium contents could be measured by flame AAS technique, by these elements significant changes were not observed as a result of nitrogen doses.
Keywords: zinc fertilisation, foliar, maize