Produção de pimentão submetido a estresse hídrico e silicato de potássio em cultivo protegido

Abstract

The present study evaluated the hypothesis that application of potassium silicate on leaf, sweet pepper plants Capsicum annuum L. (Solanaceae) is able to reduce the negative effects of water stress under greenhouse conditions. The yield (kg ha-1) and quality (leaf area index, length, diameter, shell thickness and weight of fresh fruits, dry fruits, and number of fruits / plant with and without anomalies) were quantified chili . Sweet pepper plants, hybrid Magali R cultivar, were submitted to four soil water tensions about -15, -25, -35 and -45 kPa and three levels of potassium silicate (K2SiO3) (0.0, 4, 3, 8.6 kg ha-1 of Si) via foliar application. The experimental design was randomized blocks with split plot in a 3x4 factorial design (doses of potassium silicate x soil water tension), totaling 12 treatments with four replications. The stipulated values of soil water tension were formed by sufficient levels ranging from enough water supply to the plant to water deficit, and also intermediate values. The management of irrigation was performed with the help of water retention curves for the soil and tensiometers. It was done weekly applications of potassium silicate with the help of a sprayer, a total of 21 applications. The applications of potassium silicate foliar did not increase uptake and accumulation of Si in the leaves and fruits of sweet pepper, however, there was an increased leaf area and decreased incidence of blossom end rot disease in fruit. The application of potassium silicate showed no increase in efficiency in the use of water by plant and did not interfere in the yield.