This study analyzed the macro and micronutrient content of maize leaves (Zea mays L.) grown in soil containing tannery sludge vermicomposting and irrigated with wastewater. The arrangement of the treatments consisted of a factorial 2x6 (two types of irrigation and six kinds of fertilizer) in a completely randomized design, with five repetitions, totaling sixty experimental units. The following experimental units, irrigated with supply water (A) and household wastewater (R), were established: (T1) Control Soil, with no chemical fertilization and no vermicomposting; (T2) Soil + NPK; (T3) Soil + primary sludge vermicompost; (T4) Soil + P + primary sludge vermicompost; (T5) Soil + P + liming sludge vermicompost; and (T6) Soil + liming sludge vermicompost. For the leaf-tissue analysis, the opposite whole leaf below the first (upper) ear was collected from each plant, excluding the midrib at the onset of the female inflorescence. The results showed that both wastewater and the tannery sludge vermicomposts can be a good source of nutrients for maize plants, since the macro and micronutrients in the leaves of plants were satisfactory and no signs or symptoms of toxicity were observed. While leaf analysis alone is insufficient to assess the nutritional status of plants, this study innovatively suggests the potential beneficial use of a combination of wastewater and tannery sludge vermicompost in the cultivation of corn, motivating new research.
Keywords:
agro-industrial wastes; macronutrients; micronutrients; wastewater reuse.
