Physiological responses of coffee plants at initial vegetative growth submitted to mepiquat chloride and water avaiability

Abstract

The aim of this work was to investigate growth alteration induced by foliar application of mepiquat chloride of coffee plants cv. Catuaí Vermelho 144 IAC under different water regimes. The trial was carried out in the experimental area of the State University of Southwest Bahia, Vitória da Conquista campus, from January 2014 to April 2014. Two assays characterized by availability and water restriction, were defined by ranging from two and 15 days consecutive periods after which the field capacity was reestablished. The experimental design was a randomized block, represented by five concentrations of mepiquat chloride (0; 50; 100; 150; 200 mg a. e. L-1) applied by foliar sprinkling, with five replicates. Foliar sprinkling of mepiquat chloride provides morphological and physiological changes in coffee plants, reduced vegetative growth and increased the percentage of root dry matter. These alterations are dependent on the applied dose and the water regime. Under a longer period of water restriction doses up to 200 mg a. e. L-1 of mepiquat chloride applied in coffee canopy raises the water potential modulus, but has little relevance to the initial vegetative growth of Arabica coffee plants cv. Catuaí Vermelho.