Tipburn is a physiological disorder in lettuce caused an by inadequate supply of calcium, mainly in young leaves. In this trial different management systems were evaluated in order to provide calcium and to increase the stream of calcium and reduce tipburn. Five treatments were studied in block design with five replications: Water; Solution with 100 mg Ca.L-1; Solution with 200 mg Ca.L-1; Spray calcium (3 g.L-1) and Complete (complete nutrient solution). The three first treatments were applied at night to promote the root pressure and translocation of calcium to young leaves; during the day all treatments received a complete nutrient solution. More developed plants were more susceptible to tipburn. Solution with 200 mg Ca.L-1 treatment increased the concentration of calcium in young leaves, but the low incidence of tipburn during the trial made the assessment of the treatments efficiency difficult. Even the treatments without all the essential nutrients during the night, didn't show nutritional deficiency and produced plants with suitable weight according to commercial standards.
Lactuca sativa L.; nutrient solution; root pressure; tipburn
