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Cruz das Almas, Brazil

Dias N.S.,DCAT UFERSA | de Lima F.A.,UFERSA | da Silva C.R.,Federal University of Uberlandia | Neto O.N.S.,UFERSA | Gheyi H.R.,UFRB
Revista Caatinga | Year: 2011

In order to evaluated the impact of the high salinity reject brine from reverse osmosis desalination on hydroponics lettuce cultivated in greenhouse an investigation was carried out in Mossoro, Northeast of Brazil (5°11'S, 37°20'O and 18m above sea). Two lettuce cultivars ('Verônica' and 'Babá de verão') were cultivated with a basic nutrient solution with 1.1 dS m -1 (control) during the crop cycle (1-28 days after transplanting - DAT) - T 0 and with basic nutrient solution containing 50% of the reject water from desalinization with 4.8 dS m -1 exposed during 1-7, 21-28, 7-14 e 1-28 DAT (T 1, T 2, T 3 and T 4, respectively). The addition of 50% of brine reject from desalination into the hydroponic nutrient solution allows grow only 'Veronica' lettuce with no reduction in fresh biomass. This lettuce cultivar shows to be more tolerant to salinity for all exposure time with reject brine in the nutrition solution, despite the fact that 'Babá de Verão' cultivar is more productive.

Neto C.P.C.T.,Emater | de Medeiros J.F.,UFERSA | Gheyi H.R.,UFRB | Dias N.S.,UFERSA | And 2 more authors.
Revista Brasileira de Engenharia Agricola e Ambiental | Year: 2012

A study was carried out aiming to investigate management strategies for use of brackish water in the accumulation of dry matter and nutrients in two cultivars of melon (C1 - Sancho and C2 - Medellin) irrigated with low (S1 = 0.61 dS m-1) and high (S2 = 4.78 dS m-1) salinity water in different phases of crop: S1S1S2S2 - T1, S2S1S2S2 - T2, S2S2S1S2 - T3. The 1st, 2nd, 3rd and 4th term correspond, respectively, to different phases - initial growth, flowering, fruit maturation and harvest. Alternate irrigation during the crop cycle, two days of consecutive application with S1 water followed by one day with S2 water (S1 2 days + S2 1day - T4) and irrigation with S2 water throughout the cycle - T5 was also tested. Furthermore, as control, management practice at the farm where the experiment was conducted consisting of irrigation with a mixture of 37% S1 water and 63% of S2 water -T0 was used. The experiment was conducted in a completely randomized design in a 6 × 2 split-plots with four replications. The total dry matter accumulation in shoots of cv. Sancho was greater than Medellín in all management strategies. The nutrients required most by the two cultivars were calcium, potassium and nitrogen.

de Medeiros D.C.,Federal University of Rio Grande do Norte | de Medeiros J.F.,UFERSA | Barbosa M.A.G.,UFRB | Queiroga R.C.F.,UFERSA | And 2 more authors.
Revista Brasileira de Engenharia Agricola e Ambiental | Year: 2012

The region of Mossoró, RN, Brazil, underwent increasing problems with soil salinity and melon crop yields, mainly in areas with intense evaporation, deficient drainage and inadequate fertilizer use. With this concern, dry mass accumulation in different muskmelon plant organs was evaluated in a trial combining different irrigation water salinity levels and crop growth stages. The experiment was conducted in completely randomized block design with split plot arrangement, having four replications. Five irrigation water salinity levels (0.54, 1.48, 2.02, 3.03 and 3.90 dS m-1) were kept in main plots while the sub plots were assigned to four plant growth stages, represented by sampling during the stages of initial growth, full flowering, full frutification and harvesting stage (15, 30, 45 and 60 days after transplanting, respectively). Growth parameters were all influenced by irrigation water salinity. Water salinity affects the specific leaf area and shoot dry mass varied according to plant growth stage. Variables most affected by irrigation water salinity were leaf area and fruit dry mass, with decrease of 28.9 and 24.6%, respectively. The higher dry mass accumulation of "Pele de Sapo" muskmelon occurred between 30 and 45 days after transplanting.

Santos Junior J.A.,Federal Rural University of Pernambuco | Gheyi H.R.,Nucleo de Engineering de Agua e Solo | Cavalcante A.R.,UFRB | Dias N.S.,UFERSA | Medeiros S.S.,Nucleo de Recursos Hidricos
Engenharia Agricola | Year: 2016

In view of the specific characteristics regarding infrastructure, soil, climate, hydrology and social conditions of the Brazilian semi-arid, it is of paramount importance the use of alternative cropping systems, which take into account such features, as well as considering local water quality. In this sense, our study aimed to evaluate saline stress effects on sunflower production and post-harvest which are grown in an alternative low-cost hydroponics. Experimental design consisted of completely randomized blocks in 4 × 3 factorial scheme, with three replications. Treatments assessed the effect four salinity levels in hydroponics nutrient solution (1.7 - control, 4.3, 6.0, and 9.0 dS m-1) on crop production of three sunflower cultivars ('Sol Noturno', 'Bonito de Outono', and 'Anão de Jardim'). Our results showed that even at a maximum salinity level in nutrient solution (9 dS m-1), number of petals postharvest life remained within commercial standards for both 'Sol Noturno' and 'Anão de Jardim' cultivars.

Coelho E.F.,Embrapa Mandioca e Fruticultura | Costa F.S.,Federal University of Campina Grande | da Silva A.C.P.,UFRB | Carvalho G.C.,Federal Rural University of Pernambuco
Revista Brasileira de Engenharia Agricola e Ambiental | Year: 2014

The objective of this study was to evaluate the effects of concentration of urea and potassium nitrate in the irrigation water on the concentration of nitrate in the soil solution and in saturation extract of soil at two depths of root system of Plaintans banana cv Terra Maranhão under fertigation. The experiment was carried out during the period of January to December, 2008 and followed a randomized block design with three replications in a 2 × 4 factorial scheme where treatments consisted of the use of two nitrogen sources (urea and potassium nitrate) under four concentrations (2.7; 4.0; 6.5 and 7.2 g L-1), applied by drip irrigation with three 4 L h-1 emitter per plant. Soil and soil solution samples were collected monthly in all treatments at depths of 0.30 and 0.60 m and nitrate concentration was determined in the soil solution and saturation extract. Results allowed to conclude that the increase of nitrogen fertilizer concentration in fertigation water caused an increase of nitrate ion concentration in the soil solution and in saturation extract for the two applied sources.

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