Estratégias de aplicação de efluente de água cinza no cultivo do girassol ornamental

Abstract

Due to the scarcity of good quality surface water, water reuse becomes an imperative practice to improve water supply and expand agricultural farming areas. Several research with the use of domestic sewage effluents have been developed, seeking to ensure economic and socio-environmental sustainability. Thus, the purpose of this study was to evaluate the potential of agricultural use of grey water in ornamental sunflower cultivars. The experiment was conducted in a leaky substrate with coconut fiber using the randomized block delineating with subdivided plots (5 x 2) and 4 repetitions, totaling 120 experimental units. In the experimental parcels were tested five mixtures of the wastewater treated grey Water (ACT) and Water Supply Public (AA) (100% AA; 25% ACT + 75% AA; 50% ACT + 50% AA; 75% ACT + 25% AA and 100% ACT) and in the subplots the two ornamental sunflower cultivars (Beautiful autumn assortment and red sun). The variables analyzed were plant height; Shoot diameter; Number of sheets; Foliage area; Fresh phytomass of the aerial part; Dry phytomass of the aerial part; External diameter of the chapter; Number of petals in the chapter; beginning of flowering; Post-harvest duration; Foliar content of macronutrients and micronutrients, as well as the physico-chemical and biological characteristics of water. The data obtained through laboratory procedures were subjected to analysis of variance and regression. The analysis of the variance indicated significant effect of the factors treatments and days after germination on the growth variables. The results pertaining to phytomass and flower production indicated that only the cool Phytomass variables (leaves, stem and chapter), Phytomass Dry (leaves, stem) and external and internal diameter suffered significant effects of the application strategies Used in the irrigation of the two ornamental sunflower cultivars. No significant effect has been observed of the application strategies under the concentrations of macronutrients and micronutrients. The application strategy of (100% effluent) presented higher averages for the growth variables diameter of the stem, number of leaves and area at the end of the experiment. The cultivating Red Sun presented better commercial quality when fertirrigadas with the due application strategies