Gesso agrícola: efeitos no crescimento radicular e no rendimento de grãos da soja

Abstract

The response to gypsum, as the root environment conditioner in depth has been observed for most annual crops. Such responses are attributed to better distribution of roots deep in crops in the soil by reducing chemical impediments caused by exchangeable aluminum and calcium deficiency in these layers, which provides the plants to take advantage of higher volume of water when dry spells occur. Thus, the aim of this study was to evaluate the effects of gypsum rates on root growth in yield of soybeans. The experiment was conducted at the Agronomic Institute of Paraná (IAPAR) in Santa Tereza do Oeste - PR. The soil was classified as Typic Harplortox (EMBRAPA, 2013) which comes without the managed under no-till 18 years. The experiment was conducted in randomized blocks in a factorial design with plaster 5 doses as treatments (0, 3, 6, 9 and 12 t ha-1) and six repetitions. For this statistical analysis we used the System for Analysis of Variance (SISVAR®) and ASSISTAT Version 7.7 beta (2016) regression analysis. The physical attributes soil density, total porosity, microporosity, macroporosity and saturated hydraulic conductivity soil did not differ significantly with the application of gypsum rates, but in the 0.1 - 0.2 m layer, by the concentration of pressure imposed by the machines and agricultural implements, it underwent deformation, providing differences of these attributes in this layer. There wasn't significant difference in grain yield and root growth of soybean.