Mineral Fertilizer Microdosing Alone or Combined with Urea on Maize and According to the Soil Chemical Elements Variation (Thies, Senegal)

Mineral fertilizer microdosing is a technique developed not only to compensate for the low availability of mineral fertilizers but also to optimize their removal by the crop. A microdose experiment on a maize crop (rainfed) was conducted at The Center for Application of Agricultural Techniques (CATA) of the National School of Agriculture of Thies (ENSA). The aim of this experiment was to evaluate the effect of 15-15-15 (NPK) mineral fertilzer microdosing on maize production and on the variation of soil chemical elements. The experimental set-up was a Split plot with three replicates. An absolute control, one extension dose and six microdoses derived from the combination of three doses of 15-15-15 (NPK) mineral fertilizer (2 g, 3 g and 4 g per pot) and two doses of urea (U) (0 g and 2 g per pot) were tested on Sooror and Gwana maize varieties. The parameters studied were growth, yields, yield components and soil nutrients content. The results obtained show that the microdose had significant or very highly significant effects depending on the treatments on maize production. Fertilizer doses combining NPK and urea (NPKU) by microdose increased maize production compared to the control and extension dose. At the NPK3U dose, the microdose increased grain yield by 132% to 36% compared to the control and extension dose, respectively. Compared to the control, soil pH decreased at all doses. All treatments resulted in a decrease in soil nitrogen content, except for the NPK4U rate. Soil phosphorus and potassium levels showed positive rates of change compared to the control. The NPK2U treatment, which had comparable grain yield to the NPK3U treatment and an acceptability index of 1.8, is most recommended.