The plants population is very important in optimizing of the maize vegetation factors regime, the researches were carried out in the Agricultural Research and Development Station Oradea during 2006-2009. Turda super is one of the most known cultivar from the area, was use five graduation of the plants population (of 25000 plants/ha, 40000 plants/ha, 55000 plants/ha, 70000 plants/ha and of 85000 plants/ha) and studied their influence on yield in unirrigated and irrigated conditions, on water consumption, water use efficiency and irrigation water use efficiency. In the irrigated variant, for maintaining the soil water reserve on watering depth (0-75 cm) between easily available water content (2240 m3/ha) and  field capacity (2782 m3/ha ) the soil samples were prelevated ten to ten days; the sprinkler irrigation was used. The experiment had four repetisions placed by block methods. Total consumption of the crop increased together with the plants population increase based on the use of the soil water reserve but the water consumptin of the every plants decreased together with plants tickness increase. The biggest yields were obtained in the variant with 55000 plants/ha in the unirrigates conditions but in the drought years the best plant population was 40000 plants/ha. In six years the best plant population for irrigated conditions was 70000 plants/ha. These plants population determined the bigest average yields for every meter of water used and the bigest yields gains for every meter of irrigation water used. The researches sustain the known need of the meteorological prognosis because in the droughty years a plants populations with 25-30% smaller than optimum value is recomanded. The researches were carried out in the project: PN-II-ID-PCE-2008; 1103/2009 ”Study of the relationships in the soil-water-plant-atmosphere system on the land affected succesivelly by excess and deficit of moisture from North Western Romania regarding the improve of the yield quantity and quality”.

maize; plants population; water use efficiency; irrigation

Presentation: oral