The objective of this work was to evaluate the effect of desalination wastewater on the post harvest quality and conservation of lettuce, cultivars Verônica and Quatro Estações, produced in hydroponic system with coconut fiber. The test was developed in an protected environment from the Department of Environmental Sciences of Universidade Federal Rural do Semi-Árido, located in Mossoró/RN, installed in an experimental design of randomized blocks, in factorial scheme 2 x 2 x 5, with three replicates, the treatments consisted of two lettuce cultivars (Verônica and Quatro Estações), two times of evaluation (at the time of harvest and after three days of conservation) and five levels of salinity of the nutrient solution with or without a further dilution of the tailing desalination of brackish water (1.1; 2.4; 3.6; 4.7 and 5.7 dS m-1). Quatro Estações cultivar showed lower weight loss during the conservation period and higher total value of chlorophyll and pH. The matter of vitamin C and soluble solids were influenced by the reuse of tailing from desalination in nutrient solution, presenting higher level in the highest salt content studied. The cultivated lettuce on coconut fiber irrigated with reuse of the tailing nutrient solution in desalination presented, in general, good appearance both at harvest and after three days of conservation.

In order to study the effect of nitrogen sources upon the yields and nutrition of corn for silage and on the chemical attributes of a Cambisol, at Northern of Minas Gerais, Brazil, under calcareous water. The cultivar used was Decalb 390®, with a spacing of 0,8 m x 0,2 m. The base fertilization consisted in 330 kg ha-1 of formulation 4-30-10 and 50 kg ha-1 of FTE-BR12. Two equal dosages of 40 kg ha-1 of K2O, in the KCl form, were applied 45 and 60 days after corn sowing (DAS), phenologic phases V7 and V10 . The experiment it was realized in a randomized blocks design with six repetitions, been the treatments constituted by: ammonium sulfate (topdressing manuring), urea (topdressing manuring), Crotalaria juncea (before de maize crop). The Nfertilizers were applied parceled into three equal dosages of 40 kg ha-1, 30 DAS, with 15 days between fertilizations. The corn yields increased above control treatment average in 33, 27 and 14 t ha-1 with ammonium sulfate and urea topdressing and with C. juncea pre cropped, respectively. The ammonium sulfate use allows better recovery rate of the N applied by the extractor and higher uptake of Fe, Mn, Zn and S by the corn plants.