Semi-hydroponic cultivation of fertigated curly lettuce with calcium nitrate-enriched saline solutions

ABSTRACT Lettuce is a leafy vegetable sensitive to salinity, and under saline stress conditions it presents nutritional imbalance, mainly in calcium absorption. Thus, the objective was evaluate effect of enriching nutrient solution with nitrate solutions prepared water lettuce crop. A completely randomized design used, five treatments four replicates. The were represented by [S1 - standard (SNP); S2 SNP + NaCl (3.5 dS m-1); S3 Ca (NO3)2 (50% = 6.86 mmol L-1); S4 Ca(NO3)2 (100% 9.15 S5 (150% 11.43 L-1)] from curly group, cv. Elba. After preparing solutions, had following electrical conductivities: 1.8 (S1); 4.8 (S2); 5.4 (S3); 6.0 (S4); 6.6 (S5) m-1. Variables growth, nutrition postharvest quality evaluated. With exception stem diameter, number total leaves, plant pH vitamin C content, other variables affected extra addition solutions. cv Elba grown coconut fiber tolerant salinity m-1 (S2). In where use 3.5 for preparation unavoidable, doses crop not recommended.