Cultivares de trigo submetidos a déficit hídrico

Abstract

Brazil is looking for self-sufficiency in the production of wheat (Triticum aestivum L.). However, with the development of cultivars adapted to the edaphoclimatic conditions of the cerrado, management and irrigation techniques, make possible the cultivation of wheat in the Cerrado region of Brazil MatoGrossense, with significant production potential. In the face of this dynamics, the objective is to test the effects of soil water stress on the growth, development and production of cultivars of wheat cultivated in oxisol of the Cerrado of Mato Grosso. The experiment was conducted at the Federal University of Mato Grosso, Campus of Rondonópolis, in a greenhouse, with a randomized complete block design in a 3x5 factorial scheme, with three wheat cultivars (BRS 254, BRS 294 and BRS 264), and five availabilities (5, 15, 25, 35, 45 kPa) with four replicates, making a total of 60 experimental units. Irrigation management was carried out based on soil water stresses using tensiometers that were installed in the pots at 10cm depth, and the tensile readings were performed using a digital tensiometer. Irrigation was performed to maintain the stresses of each treatment, with the blade calculated according to the soil water retention characteristic curve obtained previously through an assay. Variables of the vegetative development, productive, and consumption and efficiency in water use of wheat cultivars were analyzed. The data were submitted to analysis of variance at 5% and 10% of probability and, if significant, submitted to the Tukey mean test and polynomial regression using the SISVAR software. The water restriction negatively influenced most of the morphological, productive parameters, efficiency and water use of the wheat cultivars, presenting a linear decreasing response as the soil water tensions increased. The cultivar BRS 254 showed greater sensitivity to the water deficit, showing a greater reduction in the studied variables as the water restrictions increased. The cultivar BRS 264 was shown to be less sensitive to water deficit, producing higher shoot dry mass, SPAD chlorophyll index, number of ears and grains, even with a lower cycle.