Frederico Antonio Loureiro Soares

Desenvolvimento e produção de duas cultivares de mamoneira sob estresse salino

With the objective of studying the behavior of two cultivars BRS Paraguacu and BRS Energy of castor bean (Ricinus communis L.), irrigated with four levels of electrical conductivity of irrigation water (ECw: 0.7; 2.7; 4.7 and 6.7 dS m-1, at 25 °C), an experiment was conducted in a randomized design with 3 replications, in a factorial scheme of 4 x 2. The variables measured were: plant height, stem diameter, leaf area, number of leaves and water consumption by plant at 80 and 100 days after sowing (DAS), number of days for emission of first inflorence and height of first cluster at 100 DAS, days to harvest, number of fruits in the 1st cluster, weight of fruits, and 10 seeds at 150 DAS. The salinity of the irrigation water significantly affected the plant height, stem diameter, number of leaves, leaf area and water consumption starting from ECw 4.7 dS m-1 at 80 and 100 DAS of both cultivars. The cultivar BRS Energy showed early emission of the first inflorence and a greater height of cluster, while, the cultivar BRS Paraguacu showed lesser fruits and seeds and had a higher weight of 10 seed.

Germinação e crescimento inicial de genótipos de cajueiro anão-precoce em condições de salinidade

Foram avaliados, em casa-de-vegetacao, os efeitos de quatro niveis de condutividade eletrica da agua de irrigacao (CEa: 0,7; 1,4; 2,1 e 2,8 dS m-1, a 25 oC) contendo Na:Ca:Mg na proporcao equivalente 7:2:1, sobre a germinacao e o crescimento inicial, durante 50 dias, de cinco clones de cajueiro anao-precoce (Anacardium occidentale L.): CCP06, CCP09, CCP1001, EMBRAPA50 e EMBRAPA51. O experimento foi conduzido em blocos ao acaso e esquema fatorial 4 x 5, com 4 repeticoes. Avaliaram-se, tambem, as variaveis de germinacao (dias e percentagens de plântulas emergidas) e de crescimento (altura de planta, numero de folhas, area foliar e fitomassa de raizes, da parte aerea e total). A maioria das variaveis estudadas foi influenciada pela salinidade da agua de irrigacao e variou entre clones sem, entretanto, haver efeito interativo desses fatores. Em CEa de 1,48 dS m-1 foi obtida uma producao relativa de 90% da fitomassa total, podendo este valor ser considerado limite de tolerância a salinidade, para o crescimento inicial do cajueiro anao-precoce. Em geral, os clones EMBRAPA51 e CCP1001 foram os de menor e maior desenvolvimento, respectivamente, em todo o periodo de estudo.

Uso de água residuária de origem urbana no cultivo de gérberas: efeito nos componentes de produção

The objective of the present study was to evaluate the viability of four depths (equivalent to 75; 100; 125 and 150% of crop evapotranspiration) of wastewater from urban origin in production of gerbera (Gerbera jamesonni), commercial type Rambo and contrast the results obtained with those adopting conventional management (organic and chemical manuring and irrigation with urban supply water equivalent to 100% evapotranspiration). The experiment was conducted on a greenhouse of Universidade Federal de Campina Grande - PB - Brazil, during February to July 2006, during a complete cycle of production. The experimental design consisted of randomized blocks with three replications. The variables monitored were number of flowers buds and emission interval, number of flowers collected and interval of harvest, diameter of flowers and length of flower stems. For the monitored variables, only length of flower stem presented significant effect among the depths of irrigation with wastewater. The adoption of management with wastewater showed superiority for the variables evaluated in relation to conventional management except the length of flower stem. These results demonstrate that the use of wastewater constitutes an important source for supply of nutrients and water to gerbera crop increasing the potential of compatible productivity or better than the conventional production techniques.

Produção de girassol sob estresse salino e adubação nitrogenada

SUMMARY : SUNFLOWER PRODUCTION UNDER SALINE STRESS ANDNITROGEN FERTILIZATION The limited availability of low-salinity water in Brazilian semiarid region causesproducers to use water of moderate to high salinity for irrigation. In view of the increasingimportance of sunflower ( Helianthus annuus L.) in this region as a potential source of renewableenergy, this study was conducted to evaluate sunflower crops irrigated with different watersalinity levels (ECw) and fertilized with nitrogen. The experiment was conducted in a greenhouseof the Federal University of Campina Grande (UFCG), from July to October 2009, in arandomized block design, to test five ECw levels (0.5 - control, 1.6, 2.7, 3.8, and 4.9 dS m -1 )and four N rates (50, 75, 100 and 125 % of the rate recommended for pot experiments) in a5 x 4 factorial scheme, with three replications. The salinity of irrigation water and nitrogenfertilization affected the sunflower plants in independent ways. Water salinity affected the leafarea, biomass of aerial parts and roots, weight and total production of achenes and harvestindex linearly and negatively. Higher N rates on the other hand reduce the crop cycle andperiod from achene formation to physiologic maturity, and increased its mass.Index terms:

Produção do girassol sob diferentes lâminas com efluentes domésticos e adubação orgânica

The use of wastewater in agricultural production promotes the sustainability of the irrigated agriculture, saving non polluted surface waters maintaining the environmental quality and serving as a source of nutrients for plants. In this manner, an experiment was conducted under greenhouse conditions, at the UFCG, to study the production of the sunflower irrigated with domestic effluent and different levels of organic manure from July to October 2008. A randomized block design was used, with 5 levels of water necessity of the crop: 40, 60, 80, 100 and 120% determined by water balance study and 4 doses of organic manuring (control - 0, 0.7, 1.4 and 2.1% on weight bans) arranged in 5 x 4 factorial design, with 3 repetitions. The organic manure until the dose of 1.4% reduced the number of days for blooming of the sunflower (IF) and with 1.5% promoted maximum plant height. With the exception of IF the levels of water reposition favored the height of plant, dry weight of the aerial part, diameter of external and internal capitulum, fresh phytomass of the capitulum, number of achenes and dry weight of achenes per plant, the highest being observed with 120% replacement level. The wastewater is a potentially viable source of water supplement for sunflower, cv. Embrapa 122/V-2000.

Crescimento e rendimento do algodoeiro BRS-200 com aplicações de cloreto de mepiquat e lâminas de irrigação

Aiming to contribute to the elevation of technological level in cotton cultivation, this work was carried out in EMBRAPA Cotton Experimental Station in Barbalha, Ceara State, Brazil, in the period of August to November, 2003, with the objective of studying the growth and yield of BRS 200 Brown cotton submitted to four doses of mepiquat chloride (0, 50, 75 and 100 g i.a. ha-1) and five irrigation levels (125.30, 298.35, 353.89, 521.86 and 741.64 mm), in randomized block design, with 4 replications. The irrigation with 741.64 mm resulted in a 339% increase in cotton yield. There was no interactive effect between irrigation levels and mepiquat chloride factors, but the growth regulator, at 100 g i.a. ha-1, reduced the growth variables without affecting the yield or the first cotton boll opening.

Produção de aquênio do girassol irrigado com água salobra

The aim of this study was to determine yield components and achene production of sunflower (Helianthus annuus L.) variety Embrapa 122/V-2000 irrigated with water of different salinities in a greenhouse. The treatments consisted of six levels of salinity of irrigation water (ECw), N1 - 0.5, N2 - 1.0; N3 - 2.0; N4 - 3.0; N5 - 4.0 and N6 - 5.0 dS m-1 at 25 oC in a randomized design with five replications. The internal diameter of the chapter, number of seeds, weight of 100 seeds, the total mass of seeds, dry weight of shoot and root, ratio of dry weight of root and shoot, water consumption, electrical conductivity of drainage water and the saturation extract of soil. The total mass of seeds and number of seeds decreased 11.39 and 9.64%, respectively, with per unit increase in electrical conductivity of irrigation water, the root dry mass was more affected by salinity of irrigation water than dry mass of aerial parts, salinity levels of drainage water at the end of experiment were about 2.2 times of electrical conductivity of saturation extract.

Crescimento e consumo hídrico de pinhão manso sob estresse salino e doses de fósforo

Soil salinity reduces the absorption of water by plants, consequently their growth and production. Aiming to evaluate the growth of the physic nut as a function of irrigation with saline water during the third year of growth, an experiment was conducted in a protected environment, adopting a randomized block with a 5 x 2 factorial design consisting of five levels of electrical conductivity of the water used for irrigation - ECw (0.6; 1.2; 1.8; 2.4 and 3.0 dS m -1 ) and two levels of P 2 O 5 per year (135 and 200 g per plant) and four replications. Plants were cultivated in pots of 200 L and irrigated at intervals of three days. The increase of ECw, starting from the 30th day after pruning (DAP), caused significant reduction in the variables: stem diameter, leaf number and leaf area. The leaf area and number were most affected and therefore are the best indicators to express the effects of water salinity on the physic nut. The salinity of the irrigation water interferes negatively in dry-m atter accumulation in the leaves, and the mean water consumption of the physic nut is reduced by about 60% when irrigated with water with the highest ECw in relation to the lowest. Leaf area was the only growth variable influenced by phosphorus levels in the three evaluations, where leaf number was influenced at 30 DAP. This physic nut crop demonstrates sensitivity at water salinity levels above 1.6 dS m -1 .

Cultivo de girassol em sistema hidropônico sob diferentes níveis de salinidade

Hydroponic systems have constituted an alternative for combating the adverse natural factors of agricultural production in the semi-arid regions of Brazil, such as shallow rocky and infertile soils, and the scarcity of good quality water resources (high salt content). This work studied the yield of the sunflower (variety EMBRAPA 122/V-2000) destined for achene and fodder (phytomass) production, grown hydroponically, using coconut fiber as substrate and irrigated with brackish water of varying salinities. The experimental layout used was completely randomized into a 5 x 2 factorial design with three replications, five levels of water salinity and two planting density - with one or two plants per pot being studied. The irrigation water was composed of 50% standard nutrient solution and 50% municipal water supply, with added levels of NaCl, resulting in an eletrical conductivity (ECw) of 1.7; 4.3; 6.0; 9.0 and 11.5 dS m-1. The differential density of the sunflower plants positively affected the yield components of grain and biomass, showing greater viability when using two plants per pot.

Doses de boro e água residuária na produção do girassol

The availability of water of quality has become worldwide, a major constraint to expanding agricultural frontiers. Within this context, this study aimed to evaluate the effects of boron doses and irrigation with two types of water, wastewater and municipal supply water, on yield components of sunflower (Helianthus annuus L.) cv. EMBRAPA 122/V-2000. The study was conducted in a greenhouse at the Federal University of Campina Grande, in a randomized block design, analyzed in a 5 x 2 factorial with five B of boron (0; 1.0; 2.0; 3.0 and 4.0 mg L-1) combined with two types of irrigation water (R - wastewater and AB - municipal supply water) with three replications. Statistical analysis consisted of analysis of variance (F test) and means were compared by Tukey test to compare qualitative factors at 0.05 probability. It was found that the boron levels and types of water did not affect any varieble related to production of seeds, however, irrigation with wastewater variables positively influenced the fresh and dry leaves, stem and shoot all related to forage production.