Silicon accumulation in cauliflower grown in a protected environment with different water availability conditions

Abstract The objective of this work was to determine the accumulation of silicon in the plant components of cauliflower (Brassica oleracea var. botrytis) grown with different levels of water replacement and rates of Si. The experimental design was a randomized complete block with three water replacement conditions (40, 70, and 100% evapotranspiration), four Si rates (0, 50, 100, and 150 kg ha-1), and four replicates. Daily evapotranspiration was determined with constant water table lysimeters, with water replacement by a drip system. As a source of Si, silicon oxide was applied three times in the crop cycle - at the initial, intermediate, and final development stages of the plant. At the end of the cycle, samples of plant tissue (root, stem, leaves, and inflorescence) and soil were collected to determine Si by spectrometry. The Si content in the soil was not influenced by water replacement, only by silicate fertilization. The silicon applied to the soil increased the content of the element in the plant components, especially in the roots. Water replacement influences the accumulation of Si in cauliflower plant tissues, with lower amounts of the element under water deficit conditions.