"Águas residuárias provenientes de indústrias e seus efeitos no crescimento e desenvolvimento da mamoeira BRS nordestina".

Abstract

This research aimed to evaluate the effects of levels and types of treated wastewaters from industries on the growth and development of the castor oil plant, variety BRS Nordestina. The experiment was conducted in greenhouse of the National Center of Research of Cotton, CNPA EMBRAPA, located in the city of Campina Grande, PB. The experimental design was in entirely randomized blocks in mixed factorial scheme [(4 x 3) + 3] with three repetitions, having the following factors: three types of wastewaters and one of provisioning (Al = IPELSA - Industry of Cellulose and Paper of Paraiba S.A; A2 = COTEMINAS-S.A; A3 = ILCASA-Industry of Dairy products of Campina Grande S.A (LEBOM) and A4 = water of provisioning), three levels of available water in the soil (Nl = 100, N2 = 80 and N3 = 70% of the maximum capacity of available water in the soil) and three controls being used water of provisioning with inorganic fertilizers in basal dose manuring, with NPK (AF4), also in the presence of the levels of available water in the soil. The sources of nutrients were, respectively, sulfate of ammonium (20% N), triple superphosphate (43% P2O5) and potassium chloride (60% K20). To evaluate the growth biweekly measures of the height, diameter of the stem and total foliar area of the plant were accomplished, for the period of 135 days. The four different types of water promoted differences statistically significant in the variables height, diameter of the stem and total foliar area of the plant. The castor oil plant, variety BRS Nordestina, responded well to irrigation with treated wastewater, especially from the industry COTEMINAS, the richest and balanced in minerals nutrients among the tested ones (IPELSA and LEBOM), even considering the treatment with water of provisioning fertilized with NPK, with decrease of 16% regarding the absolute control and of 9.7% regarding the control with inorganic manuring. With the use of only water of provisioning, the castor oil plants did not begin the blooming, and they were rickety and undernourished, with symptoms of deficiencies of several nutrients, especially nitrogen and sulfur. The wastewater from COTEMINAS promoted the largest growth and development of the plants besides the production of fruits. It was verified decrease of 66% in the height of the plants, of 98% in the stem diameter and of 97% in the foliar area for the absolute control (water of provisioning without manuring NPK) when combined with the three levels of available water in the soil, comparing to the wastewater from COTEMINAS.