José Amilton Santos Júnior

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.

Eficiência do uso da água para girassol cultivado em sistema hidropônico sob estresse salino

In order to identify alternatives for the use of saline water in agricultural production, the effects of the use of brackish water in the preparation of the nutrient solution for the cultivation of sunflower (cv. EMBRAPA 122-V2000) were studied in hydroponic system on consumption and efficiency of water use for the production of achenes and biomass. A completely randomized design was used, analyzed in a 5x2 factorial scheme with three replications. The factors studied were five levels of salinity of nutrient solution (1.7 - control; 4.3; 6.0; 9.0; and 11.5dS m-1) and two plant densities - one or two plants per vessel. It was concluded that the water consumption of sunflower is a variable sensitive to the salinity of the nutrient solution, especially after the fourth week of crop, and that the efficiency of water use in the production of achenes and biomass of sunflower is greater when the plant density increases from one to two plants per vessel, even under saline stress.

Water use efficiency of coriander produced in a low-cost hydroponic system

Eficiência do uso da água na produção do coentro em hidroponia de baixo custo R E S U M O O incremento da eficiência do uso da água na produção das culturas é uma necessidade evidente em regiões com acesso restrito a este recurso e, nesses casos, a adoção de formas de cultivo contextualizadas à realidade local é imprescindível. Neste contexto, avaliou-se as implicações da variação da quantidade de sementes por célula (0,5; 1,0; 1,5 e 2,0 g) e do espaçamento entre células (7,0; 10,0 e 15,0 cm) sobre variáveis relacionadas ao consumo e eficiência do uso da água na produção de molhos de coentro (cv. Tabocas) em um “módulo hidropônico de baixo custo”, alternativo para regiões semiáridas. Adotou-se um delineamento experimental inteiramente casualizado analisado em esquema fatorial 4 x 3, com três repetições cujos dados foram submetidos à análise de variância em nível de 0,05 de probabilidade. Verificou-se que a redução dos espaços entre células proporcionou melhor relação custo benefício em relação ao consumo de água, massa produzida e custo de sementes. Recomenda-se, portanto, a adoção de 7,0 cm de espaçamento entre células e a utilização de 1,0 g de sementes célula-1; esta configuração proporcionou eficiência de 81,59 g L-1 na produção de massa verde da parte aérea e molhos de 62,4 g de massa total.

Organic fertiliser and the use of mulch in cowpea production under semiarid conditions

The reduction on crop production observed in semiarid conditions is closely linked to soils degradation in their physical, microbiological and fertility aspects. Based on this premise, the effects of different types of organic fertilizers associated to the use of mulching in the production of cowpea grown in Paraiba state, Brazil, under semiarid conditions, was studied. The research was conducted under field conditions in the municipality of Casserengue, PB, from April to July 2010. The statistical design in randomized block design with five treatments and five replicates was used, totaling 25 experimental units. Treatments consisted on application of cattle manure or biofertilizer on presence or absence of mulch, plus a control treatment, without fertilization or mulching. It was found that cowpea plants grown under the interaction between manure and mulch had higher phytomass and grain production.