Abstract:
Investigations were carried out at the State Agrarian University of Moldova to optimize the nitrogen content in the fertilization solution used in the production of tomato seedlings injected in cellular trays. Fertilization solutions with different rates of nitrogen were studied: 50; 100; 200; 300 and 400 mg/l. Initial average had the following content of nutrient elements: N- 50, P2O5 - 70, K2O - 120, Mg - 50, Fe - 14, Cu -6, Mn- 1,8; Zn -0,5; B-0,5; Mo -0,3 mg/1. The investigation showed that the increased nitrogen level in the fertilization solution can effect growth and development of tomato plants at the nursery stage. High nitrogen level in the solution showed an increase of plant height and leaf area and a reduction of dry matter content in shoots. The seedlings grown on high rates of nitrogen fertilization (300,400 mg/L) were succulent, had a weak resistance to dry weather and sun radiation, which led to a low rate of plant survival after transplanting in the open field. While high concentration of nitrogen in the fertilization solution on tomato seedlings negatively affected open field survival rates and early tomato yields, and no significant effect on total harvested yield were observed.