RESEARCH REGARDING THE INFLUENCE OF NITROGEN AND PHOSPHORUS FERTILIZERS ON WINTER WHEAT, IN THE PEDOCLIMATIC CONDITIONS IN CENTRAL OF MOLDAVIA

Winter wheat is one of the agricultural plants that reacts positively to the application of fertilizers in all soil and climatic conditions in our country. Factors that influence the effectiveness of fertilizers and create dosing difficulties, require the organization of a certain long-term experience for complex research of complex interactions plant x soil x fertilizer x climate and their effect on plant productivity, established in Secuieni in 1975.  This paper presents the results obtained in a long-term experience with chemical fertilizers (NP) in winter wheat crop, located in Agricultural Research and Development Station Secuieni Neamț (A.R.D.S. Secuieni, Neamț), during 2019-2021. The experience takes place in the experimental field of the unit, on a typical cambic faeoziom (chernozem) soil, with medium texture, and its an bifactorial type (N x P) and were placed according to the method of subdivided plots, in five repetitions: the factor A phosphorus, with the following graduations: P0, P40, P80, P120 and P160 and factor B nitrogen, with the following graduations: N0, N40, N80, N120 and N160. The winter wheat culture is part of a three-year crop rotation with beans – winter wheat - corn. Following in rotation after beans, no nitrogen fertilizers were applied at the establishment of the crop. The variety studied is the Glosa variety, created at N.A.R.D.I. Fundulea (National Institute for Agricultural Research and Development Fundulea). In the climatic conditions of the two experimental years (2019-2021) the yields obtained from the application of chemical fertilizers varied depending on the applied dose. In the first year of testing, the yield varied in very high limits, from 3232kg ha-1 in the non-fertilized version and up to 6525 kg ha-1 in the version fertilized with N120P80. In the second year, the minimum yield was obtained in the version in which no fertilizer was applied dose, of 6133 kg ha-1, and the variant in which the fertilizer doses of N120P120 were applied obtained the highest yield, of 9429 kg ha-1. On average, the factors studied greatly influenced winter wheat yield, which variet within large limits, between 4683 kg ha-1 (N0P0) and 7787 kg ha-1 (N120P120).