Growth and production of basil in NFT hydroponic system under salinity/Crescimento e producao de manjericao em sistema hidroponico NFT sob salinidade

The scarcity of good quality water in the Brazilian semiarid region has justified the growth of scientific researches on the use of brackish water. In the present study the effects of brackish water on growth and production of basil plants were evaluated in hydroponic system during October-November 2012. The treatments consisted of four levels of salinity (1.45, 3.80; 6.08 and 8.48 dS [m.sup.-1]) obtained by adding NaCl to the local fresh water, a control prepared with the fresh water (EC=0.29 dS [m.sup.-1]) and a reverse osmosis reject (EC=8.39 dS [m.sup.-1]) of a municipality in the semiarid region. Thirty six plots were randomized into six blocks. Data were analysed by analysis of variance and regression. There was a linear reduction in the production of fresh and dry matter of shoots (FMS and DMS) with increase in salinity, corresponding to respectively, 7.86 and 6.76% with per unit increase in electrical conductivity (dS [m.sup.-1]); there was no difference between NaCl and isosmotic water of desalination reject in reference to the production of FMS. The plant height and growth rate did not indicate the influence of salinity on basil. The brackish waters produced no damage symptoms in plants.