Agricultural use of wastewater is an alternative to increase water availability, especially in semiarid regions. However, it may cause undesirable chemical changes in the soil. The aim of this study was to evaluate the influence of wastewater irrigation and castor bean (Ricinus communis L.) cultivation on the chemical attributes of a Fluvic Neosol. The experimental design was in a randomized block, in split-plot scheme, where the main plots were represented by the treatments of irrigation water and castor bean cultivation, and the subplots were the soil layers, with three replications. The treatments were T1 -wastewater irrigation + castor bean cultivation ; T2 -mixture of supply water and wastewater (1:1 ratio) + castor bean cultivation; T3 -supply water irrigation + castor bean cultivation ; and T4 -wastewater application, without castor bean cultivation. The depths of soil layers were 0-10, 10-20, 20-30, 30-40, and 40-50 cm. At the end of study, the content of phosphorus, calcium, potassium, and organic matter increased mainly in the upper layers, and sodium increased in the deeper layers in the wastewater treatments, in comparison to the supply water irrigation. In T4, the disposal of wastewater increased the concentration of magnesium. The pH values, iron and zinc concentration did not statistically differ in the treatments.

Plants respond to environmental adversities, becoming an indicator for assessing the environment quality. In this aspect, chlorophyll contents as well, carotenoids are used as a reliable indicator to associate environmental quality and pollution, mainly regarding the toxicity of heavy metals in higher plants. So, we aimed to evaluate the content of chlorophyll a, b, and total chlorophylls and carotenoids in plants vetiver [Vetiveria zizanioides (L.) Nash], maize (Zea mays L.) cv. AG 1051, sunflower (Helianthus annuus L.) cv. BRS 122/V-2000, and castor beans (Ricinus communis L. ) cv . Northeastern BRS grown in contaminated soil with lead, with and without correction of soil pH, so they were used as indicators of metal stress by the soil. From the biochemical point of view, the correction of soil pH values caused chlorophyll a, b and total statistically higher for vetiver species and castor beans in the analyzed periods, except for the analysis performed 60 days after transplanting where only the species vetiver benefited from the correction of soil pH on the content of chlorophyll b and total. On the other hand plants without correction of soil pH showed a decrease of all chlorophyll levels. In addition, the largest increase in the synthesis of carotenoids, indicated that under stress the plants have developed alternative routes of dissipation of energy in order to avoid problems of photo-inhibition and photo-oxidation.

ABSTRACT:High growth rate is one of the criteria used for the selection of species to be used in metal phytoextraction programs. This study was carried out to characterize the growth characteristics of sunflower (Helianthus annuus L.), castor bean (Ricinus communis L.), corn (Zea mays L), and vetiver [Vetiveria zizanioides (L.) Nash] grown on a soil contaminated with lead (Pb), with and without pH correction, to improve agronomic practices regarding phytoremediation programs. The experiment was designed as a randomized block with four replications; treatments were arranged in a split-plot arrangement, with the main plot representing the species (sunflower, castor bean, corn, and vetiver), with or without pH correction and soil fertilization, and the split-plot representing harvest periods (60, 90, and 120 days after planting). After variance analysis and mean comparison analysis of the data by the Tukey test (p≤0.05), a significant effect was observed from soil pH correction for vetiver in all of the growth variables evaluated, except for the leaf area index at 120 days after planting (DAP). Castor bean and sunflower plants in soil with high acidity conditions, without pH correction (pH˂4.0), were affected by soil Pb levels. Corn plants benefited from soil pH correction and had improved results for the plant height, diameter, and leaf area variables at 60 and 90 DAP, as well as leaf area index at 60 DAP. There was no increase in these variables between the harvest periods evaluated. Regarding phytoextraction potential, corn and vetiver had the highest Pb translocation to the plant shoots at 90 DAP and were therefore considered the most suitable species for phytoremediation of the area under study. Overall, liming was essential for improving species biomass production for all the species studied in soils with high Pb availability in solution.

RESUMOO pinhão-manso (Jatropha curcas L.) é uma planta produtora de óleo atualmente considerada uma alternativa para produção de biodiesel. Objetivou-se com esta pesquisa avaliar os efeitos da aplicação de diferentes níveis de reposição da evapotranspiração, através da irrigação com água salina, e efeitos da adubação orgânica e mineral, sobre as concentrações de elementos nas folhas das plantas de pinhão manso, sob condições de campo. O experimento foi desenvolvido na Fazenda Barra, no município de Santa Luzia, no semiárido paraibano. O delineamento experimental utilizado foi em blocos casualizados, em um esquema de parcelas subdivididas, com quatro repetições. Foram estudados dois níveis de reposição de água (25 e 125% da evapotranspiração de referência) nas parcelas e três tipos de adubação (orgânica, mineral e fertilidade natural do solo, isto é, sem aplicação de adubo) nas subparcelas. As concentrações de fósforo, potássio e boro não foram influenciadas significativamente pelas lâminas de água ou pelas adubações aplicadas. As menores concentrações foliares de nitrogênio foram obtidas nas plantas que não receberam nenhuma adubação e foram irrigadas com menor lâmina de água. Nas plantas que receberam adubação orgânica ou mineral, as maiores concentrações foliares de sódio foram obtidas nas plantas que receberam a menor lâmina de irrigação. Palavras-chave: Jatropha curcas L., salinidade, evapotranspiração. EFFECT OF FERTILIZATION TYPES AND WATER SALINA BLADES IN PHYSIC NUT LEAVES UNDER FIELD CONDITIONSABSTRACT The physic nut (Jatropha curcas L.) is an oil producer plant currently considered an alternative for biodiesel production. The objective of this research was to evaluate the effects of different levels of replacement of evapotranspiration by irrigation with saline water, and effects of organic and mineral fertilizer on the concentrations of elements in the leaves of Jatropha curcas under field conditions. The experiment was carried out at Barra, in Santa Luzia, in the semiarid region of Paraíba. The experimental design was randomized blocks in a split plot with four replications. We studied two levels of water replacement (25 and 125% of reference evapotranspiration) in the plots and three types of fertilization (organic, mineral and

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