Corretivos de acidez do solo para a cultura do trigo sob déficit hídrico

Abstract

The silicon, although not a plant nutrient, plays an important role in mitigating the effects of water stress. In this sense, the aim of this work was to evaluate the use of silicate of magnesium in comparison to limestone under conditions of controlled water deficit for wheat (Triticum aestivum) cultivar Br 18 Terena. The experiment was conducted in a greenhouse from March to August 2017. The experimental design was a randomized block in a 2 x 4 factorial totaling 8 treatments and 4 replications, making a total of 32 experimental units, being: two correctives of acidity of the soil (limestone and magnesium silicate) and four irrigation levels, from flowering, to maintain soil moisture based on 20, 40, 60 and 80% field capacity (CC). The agronomic attributes (number of tillers, plant height and number of spikes) were quantified, the SPAD value in the flags sheets was determined, the nitrogen concentration in the leaves flags and aerial part was measured and the gas exchanges were measured. The averages of the agronomic variables were higher with the use of limestone. The best wheat development occurred on average with 60% of the CC. Nitrogen concentrations in leaf and total leaves were not influenced by correctives and water deficit. With regard to acidity correctives, the best results for agronomic variables were chosen for liming, as for the water deficit, the water replacement based on 60% of the CC expressed the best results for most variables.