Abstract: Present-day debate worldwide, including certain nationwide approacges lead towards highly-diversified trends for the implementing of agriculture systems that involve to a higher or lesser extent the employment of feritilizers for their success. At the same time, however, they are called to provide food amounts that are both quantitative and qualitative appropriate, while increasing soil fertility and providing environmental protection. Bearing in mind the scientific basis, as well as the complex food chain effect, all agriculture systems cand be improved and cannot ultimately achieve all objectives set by human society, consumers and soil fertility requirements.In this context, the present paper aims at promoting organic fertilizing resources (stable and poultry manure) and reducing mineral fertilizers, on the grounds of the fact that organic feritlizers are easier to obtain, at lower costs, while soil fertility is manintained on a sustainable and ecologic term, compared to mineral fertilizing resources. In order to attain the previously-set objectives, field experiements were conducted at SDE Cojocna of the University of Agricultural Sciences and Veterinary Medicine, in 2011. They were set on a cambic chernozem, for maize crop, involving different fertilizing resources, mineral-from NP complex fertilizers, organic- from semifermented stable and poultry manure. The present paper reveals certain experimental results obtained through the application of differentiated mineral fertilizers (from complex NP fertilizers), organo-mineral ones (semifermented stable and poultry manure and complez NP fertilizers) and organic ones from semifermented stable manure (20t/ha) and poultry manure (12t/ha). The differentiated application of fertilizers highlights the importance of such combinations as the organo-mineral ones with stable manure, as well as poultry manure, where the grain production increases significantly compared to the (unfertilized) control. With regard to exclusively mineral fertilizing variants, production increases for increased NP doses are insignificant compared to the organo-mineral variant with a minimum NP dosis (N 50 P 50 ), in the case of stable manure, as well as poultry manure. The experience of European countries and Romania alike, at least during the last 50 years, including intensive conventional agricultural practices or one-sided technological activities, have led to the spread of disturbing processes and phenomena for the environment towards de degradation of the soil's paramount quality- its fertility. The factors of physical, chemical, biologic and technologic degradation of soils have extended and increased, while areas subjected to erosion and compacon have expanded, as well as areas degraded by polluation and the destruction of fertility. The nutrient cycle is thus blocked, while more areas show the potential of desertification. The impact of these modifications is increasingly higher in the past period due to global climate change, as in such conditions, the factors involved in the degradation of fertility become more active and more unpredictable. As such, long-term and sustainable fertility of soils has become paramount in supporting ecological balance amd incresing the safety of plant and animal production. Therefore, such research as the hereby one are beneficial for agricultural practice to increase the quality and quantity of production and provide food safety and security. The paper was supported by the project – POST-DOCTORAL SCHOOL IN THE FIELD OF AGRICULTURE AND VETERINARY MEDICINE Contract n.: POSDRU/89/1.5/S/62371

productions, nutrients, stable manure, poultry manure, maize grains

Presentation: oral