Uniformidade de aplicação de água na irrigação de mudas de espécies florestais nativas produzidas em tubetes

Abstract

Irrigation systems poorly dimensioned allied to inadequate management could affect the satisfactory use of irrigation in nurseries, causing waste of water and energy and, consequently, less species development. Thus, the objectives of this study were to evaluate the uniformity of a microsprinkle irrigation system, already installed in a nursery of forest species, as well as evaluating the uniformity of a capillarity irrigation system of forest seedlings grown in plastic tubes. The microsplinkle irrigation uniformity evaluation was performed in a native forest nursery at Itutinga city, MG, using the emitters models MA-20, Rondo e Inverted Rotor Spray. To determine the irrigation uniformity, were calculated the coefficients CUC (Christiansen Uniformity Coefficient) and DUC (Distribution Uniformity Coefficient) of each emitter, with three replications. The capillary irrigation uniformity evaluation was evaluated in a greenhouse located in the Federal University of Lavras (UFLA), in three species cultivated in 300 cm³ recipient tubes (Araucaria angustifolia (Bertol.) O. Kuntze, Syagrus romanzoffiana e Joannesia princeps) and three species cultivated in 110 cm³ tubes (Guazuma ulmifolia Lam., Anadenanthera macrocarpa (Benth.) Brenan and Aspidosperma polyneuron), through the calculation of CUC and DUC for each species, also with three replications. To the microsprinkle systems, the largest values of CUC and DUC were obtained for the MA-20 emitter. In capillarity irrigation, the largest CUC and DUC were obtained at irrigation of the Guazuma ulmifolia Lam. plants. In general, the irrigation uniformity in the species cultivated in 110 cm³ tubes was higher than in tubes of 300 cm³.