BEHAVIOR OF THE STRUCTURE OF THE VEGETABLE CARPET BY THE APPLICATION OF SOME MINERAL FERTILIZERS, UNDER THE CONDITIONS OF A.R.D.S. SECUIENI

At A.R.D.S. Secuieni (Agricultural Reseach and Development Station Secuieni) was followed the evolution of the structure of the vegetal carpet to some mixtures of perennial grasses and legumes, with mixed use, taking into account the mode and duration of use, but also the capacity of competition between the studied species. In the technology of cultivation of temporary meadows, the composition of the mixtures is the most important work because it largely depends on the yield and evolution of the composition of the plant carpet. During 2018-2020, research was carried out on three mixtures of perennial grasses and legumes, under the influence of doses of nitrogen fertilizers on phosphorus agrofund. The experience was placed on a phaeozium-type soil, according to the method of subdivided plots into a bifactorial experience, in four repetitions. In the experience, the A factor was represented by fertilization, with four graduations a1 - N0P0, a2 - N40P40, a3 - N80P40, a4 - N80 + 40P40, and B factor was represented by the mixture between grasses and perennial legumes, with three graduations b1 - 85% grasses + 15% legumes (control), b2 – 90% graminee + 10% legumes, b3 – 90% graminee + 10% legumes. In the structure of the vegetal carpet, the percentage of participation of legumes increased slightly, and the grasses had a decreasing tendency compared to the percentage of participation at the sowing norm. Various species from the group were present, and the participation percentage was between 0 - 3.1% at scythe I, with a tendency to increase from one scythe to another.