Nitrogen Fertigation in Lettuce Culture

Lettuce (Lactuca sativa L.) is the most consumed vegetable in the world and in Brazil, representing as an important dietary source of vitamins, fiber and minerals to population. The aim of this study was to evaluate the yield of lettuce against nitrogen doses applied via fertigation, as well as the quality of the administered fertilizer solution. The test was carried out in an agricultural area located in the Doutor Camargo municipality, Northwestern of Paraná State, Brazil. The experiment was designed in a completely randomized design with seven treatments- T1 control - 0 kg ha-1 urea (0 kg N ha-1); T2 - 25 kg ha-1 urea (11.25 kg N ha-1); T3 - 50 kg ha-1 urea (22.5 kg N ha-1); T4 - 75 kg ha-1 urea (33.75 kg N ha-1); T5 - application of 100 kg ha-1 urea (45 kg N ha-1); T6 - 125 kg ha-1 urea (56.25 kg N ha-1); T7 - 150 kg ha-1 urea (67.5 kg N ha-1). Each treatment had six repetitions. Seeds from Dora (American lettuce) and Vera (curly lettuce) varieties were used for seedling production. Nutrients were applied to the crop by fertigation at 15 and 30 days after transplanting the seedlings to the seedbeds. Fresh shoot mass (weight), stem diameter, root length and productivity were assessed. Results showed that nitrogen fertilization via fertigation significantly influenced the growth and yield variables of plants from both Dora and Vera varieties.