Salinity levels in growth and production of curly lettuce (Elba, Cristina and Veneranda) grown in hydroponic system

Abstract

The objective of this research was to evaluate the different salinity levels on growth and production of three cultivars (Elba, Cristina and Veneranda) of curly lettuce in a hydroponic system using the Nutrient film technique (NFT). The design was randomized blocks in a split plot scheme, in which treatments constituted of nutrition solutions: S1 = Furlani (1.9 dS m-1) and six solutions prepared from Furlani solution in order to present the electrical conductivities of (S2 = 2.4; S3 = 2.9; S4 = 3.4; S5 = 3.9; S6 = 4.4 and S7 = 4.9 dS m-1) with three repetitions. The electrical conductivities were obtained by addition of NaCl. The subplots corresponded to the cultivars Elba, Cristina and Veneranda. The following variables were evaluated: Number of leaves per plant (NLP); Total production (TP); Commercial production (CP); Stem diameter (SD); Fresh leaf mass (FLM), Dry leaf mass (DLM) and Dry stem mass (DSM). Nutritional solutions (S1 and S2) promoted the best results for all variables studied. The highest number of sheets (NS) were found in cultivars Elba and Veneranda when the solutions were used (S1 and S2). The highest yields for (TP) (PC) and (FLM) were found in the cultivar Veneranda with nutrient solutions (S1 and S2). The highest value for dry leaf mass (DLM) and dry stem mass (DSM) was found in the cultivar Veneranda