Differentiated Contribution of Minerals through Soil and Foliar Fertilization to the Winter Wheat Yield

Research has evaluated the contribution of minerals through soil and foliar fertilization on winter wheat yield, the purpose being to identify the interdependence relations for the optimization of the fertilization system. Two types of mineral and foliar fertilizers were tested. The complex mineral fertilizer of the type NPK (1:1:1) was used for achieving three differentiated nutrition levels: NPK0, NPK30 (30 kg active substance ha-1) and NPK60 (60 kg active substance ha-1). There are five types of foliar fertilizers applied and 18 experimental variants were studied. The research was conducted in Soil Science and Plant Nutrition (SSPN) and Mathematics and Statistics (MS), Banat University of Agricultural Sciences and Veterinary Medicine„ Regele Mihai I al României„ from Timisoara, Romania (USAMVBT), between 2011 and 2012. The influence of interaction between the two types of fertilizer compared to their individual influence on wheat production was analyzed. Based on regression analysis were obtained mathematical model of interdependence, reliability of the results and models have been certified by LSD, p and R2 (maximum value is better). The complex fertilizers generated yield increase between 925*** and 1425*** kg ha-1. The foliar fertilizers determined yield increase between 355 and 810*** kg ha-1 with natural soil fertility (NPK0), between 550** and 900*** kg ha-1 with NPK30, and between 500** and 795*** kg ha-1 with NPK60. The yield increase determined by the joint effect of the two types of fertilization was between 1475*** and 2220*** kg ha-1. The experimental results have high statistical confidence (p<.01; Fcrit<F for Alfa = .01). The study recorded a decrease in the potentiation effect of the foliar fertilizers and at the same time in their contribution to the winter wheat yield, when the doses of complex fertilizers applied on the soil were increased.