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Moringa oleifera is one of the most important plants in the world due to its multiple uses as well tolerance to abiotic stress. However, it may presents low quality seedlings in protected environment under thermal and luminous stresses. The current study aimed to evaluate environmental microclimate changes; photomorphogenesis and water use of M. oleifera cuttings under light spectral and phytohormones variations, as well as to identify the most important variables to explain those effects. A completely randomized experimental design was used in a 4 x 4 factorial design with four replications. Four luminosity conditions, white (a transparent plastic layer), blue (two layers of blue cellophane paper), red (two layers of red cellophane paper), and extreme red lights (one layer of red cellophane and one of alternating blue cellophane) and four phytohormones concentrations (0, 25, 50, and 100%) were applied. M. oleifera semi-woody cuttings were collected from 7 am to 9 am from the M. oleifera mother plants, grown on a rural property located in the city of Lagoa Seca, Paraíba, Brazil, with the following characteristics: 15 cm in length, 4 to 5 mm in diameter, and 2 or 3 buds. Throughout the experimental period, environments were monitored to determine illuminance, average air temperature, relative humidity, soil average temperature, and evapotranspirated water consumption by cuttings. The numbers of shoots were recorded weekly. The number of surviving roots and shoots were measured 60 days after M. oleifera cuttings planting. Illuminance was reduced in environments under blue, red, and extreme red lights, respectively. The air temperature was reduced under blue light, while red and extreme red lights induced the increase on air temperature and relative humidity, soil temperature, and therefore, water consumption of cuttings. Protected environments when irradiated with blue light and application of phytohormones at concentrations of 25 and 50% enabled the shootings and survival of cuttings, although no root formation was observed after 60 days from planting. All variables were considered important to explain the effects.

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Hydroponics has been gaining increasing interest because of its contribution to reducing environmental impacts through minimal use of water and fertilizers. The objective of this work was to evaluate the production of arugula cultivars in the harsh region of Paraíba , under hydroponic system and under different plant densities and nutrient solution concentration. The research was carried out in Campus II of the UEPB (Lagoa Seca-PB) and followed a randomized block design in the 2 x 2 x 2 factorial scheme, two cultivars of cultivated arugula (Cultivated, Broad Leaf), two plant densities (10 and 15 plants per phenolic foam) and two concentrations of the nutrient solution (100 and 120%) with four replicates. The hydroponic system used was the NFT. For the nutrient solution, a commercial fertilizer produced for leafy olives (Compound + Calcium + Iron) was used. The seedlings were produced in phenolic foam (2 x 2 x 2 cm). The cultivation beds had 8 channels (4.5 m each), where each one represented one block. The spacing used was 0.25m x 0.25m between plants and between rows, respectively. The data of the variables were submitted to analysis of variance by the F test at 5% probability and the Tukey test to compare the means. At 41 days after sowing, the growth parameters were analyzed, where it was verified that the two arugula cultivars can be cultivated satisfactorily, in a hydroponic system, under the conditions of the harsh region of Paraíba without increasing the recommended dose of the nutrient solution and plant population.

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This work aims to study the effect of castor oil plant cake doses (0.0; 1,100; 2,200 and 3,300 Kg ha

Hydroponics has drawn huge interests by Brazilians in semi-arid regions due to the lack of water and fertilizer use. The objective of this study was to evaluate the growth and yield of lettuce cultivars in the hydroponic system in two planting seasons and different irrigation regimes. The research was carried out in Campus II / UEPB and followed a 2 x 6 x 3 factorial scheme in randomized blocks, represented by two planting seasons (the summer and the winter), six lettuce cultivars (Elba, Great Lakes, Mimosa Rose, Simpson, American, Cristina), three irrigation regimes (15 min, 30 min, 45 min) and five replications. The hydroponic system used was the NFT. For nutrition, Hidrogood Fert® solution (Compound + Calcium + Iron) was applied. At the 40th day after sowing, green and dry leaf biomass, green stem biomass, leaf area, leaf area index and productivity were analyzed. After that, the variance analysis was performed by the F-test for 5% of probability and the Scott-Knott test for comparison of the averages. The high temperatures caused very small growth in the stem of the Simpson cultivars, independent of the irrigation regime used. Besides the highlight of the American cultivars, the other cultivars presented satisfactory performance in the climatic conditions of Lagoa Seca / PB.

Soil quality is a factor which is directly related to the sustainability of agricultural production and can be compromised through the use of inadequate management practices. In this work, soil edaphic respiration and changes in microbial biomass promoted by cover crops in an integrated crop-livestock system (ICLS) were evaluated using soil quality indicators by the respirometry method. The design used was completely randomized in a 3x6 factorial scheme and multivariate principal components analysis (PCA) was performed according to MANOVA. The edaphic respiration was determined based on the respirometry technique. From the results, it was found that edaphic soil respiration was significant in the nine evaluation periods, demonstrating the importance of grass cover on this edaphic respiration arising from the biological activity of microorganisms, which is directly related to the amount of organic carbon in the soil. It was concluded that the use of cover crops contributed to producing organic matter in the soil and consequently greater microbial respiratory activity.