CaSiO3 improves water potential and gas exchange but not contribute to the production parameters of maize plants exposed to different irrigation depths

Abstract

The aim of this study was to evaluate effects of different proportions of calcium silicate(CaSiO3) on leaf water potentials, gas exchange and production parameters in Zea mays plants exposed to different irrigation depths.The experiment was organized asfactorial scheme in a completely randomized design with five calcium silicate levels (0, 25, 50, 75, and 100% of CaSiO3 indicating the liming of the soil) and five irrigation depths (30, 70, 100, 130, and 160% of necessary to water reposition in this soil). The parameters evaluated in soil were chemical properties before and after the application of calcium silicate and matrix potential, while in plant the water potentials, transpiration rate, stomatal conductance, net photosynthetic rate, grain production, and matter of 100 seeds were measured. The results showed that application of 100% of calcium silicate promoted the values of predawn and midday water potentials.The beneficial effects were also observed in stomatal conductance, net photosynthetic rate and photosynthetic water use efficiency, when applied at the irrigation depths of 70, 100, 130 and 160% of necessary to water reposition in the soil. Despite that calcium silicate significantly promoted the gas exchange, the increment was not transferred to grain production and matter of 100 seeds. This study proved that irrigation depth of 100% is adequate for this crop.