Uso e manejo da água, coeficientes de cultura e qualidade de hastes florais do gladíolo

Abstract

Knowledge of the water consumption of a crop throughout its cycle is essential for good irrigation management and to ensure maximum productivity. Thus, the objectives in this dissertation were: (i) Evaluate the effects of irrigation and cultural remains on the quality of the floral stems of the gladiolus; (ii) to determine the evapotranspiration (ETc) and the crop coefficients of the gladiolus in planting systems with and without soil mulching and ; (iii) fractionate the ETc in transpiration of the crop (Tc) and evaporation of the soil (Es), deriving the coefficient of basal culture (Kcb) and evaporation (Ke). Two field experiments were carried out with two gladiolus cultivars, two planting systems (with mulching and without mulching) and two water regimes (with irrigation and without irrigation). In both experiments, plant height, soil cover fraction by crop, leaf área, and leaf area index were evaluated. The water content in the soil was monitored for the purpose of irrigation management and simulation of the soil water balance. The soil water balance model - SIMDualKc was used to estimate the ETc of the crop, fractioning it in the Es and transpiration components of the Tc plant. The results showed that the soil cover with straw did not influence the quality of flower stems of the gladiolus. Irrigation contributes to increasing the quality of floral stems of the gladiolus, providing greater plant height, longer spike length, larger stem diameter and a greater number of florets per spike. Among cultivars, only the length of the spike showed significant differences. The SIMDualKc model was calibrated and validated for gladiolus. The mean initial and final Kcb values calibrated by the model were: 0.20, 0.50 and 0.50. ETc showed differences between cultivars in different treatments, ranging from 265 to 301 mm. Es represents an important fraction of the ETc throughout the gladiolus cycle, especially when the soil is not covered, being an important parameter to be considered in the management of gladiolus irrigation.