Fenologia e fenometria do girassol em condições de déficit hídrico

Abstract

The water deficit is a factor that affects the growth and development of agricultural crops worldwide. It is directly responsible for the negative effects on crop yields as a whole. As a result, this work aimed to analyze the phenomena and phenology of a sunflower cultivar in different water deficits. For this, an experiment was arranged in a potting design in a greenhouse - of the Universidade Federal da Fronteira Sul, in the municipality of Cerro Largo - RS. The treatments consisted of 6 levels with 4 replications, being the supply of 120%, 100%, 80%, 60%, 40% and 20% of daily evapotranspiration through irrigation. The volume of water was determined by calculating the evapotranspiration using the Penman-Monteith method, applying a correction factor of 0.7, as a function of being calculated with the external environment data, from the automatic meteorological station installed at 400 Meters of the greenhouse. The data obtained in the experiment were submitted to analysis of variance and regression and a positive response was verified to the water supply. However, in most of the analyzed parameters, the sunflower crop suffered a 20% deficit in the water supply without losses in the analyzed variables.