Condições edafoclimáticas para o cultivo do linho em Latossolo caulinítico em Dourados, MS

Abstract

The soil water is indispensable for agricultural production, the knowledge of their interaction with the soil-plant-atmosphere system enables the establishment of a proper agricultural management to optimize their use by crops. The aim of this work was to evaluate the edaphoclimatic conditions for the cultivation of flax (Linun Usitatissimum) in kaolinitic Oxisol in Dourados, MS. The experiment was carried out in a Haplustox which was sown three genotypes of brow flaxseed: Caburé INTA, Aguará INTA-Argentina and UFSC-Brazil in April of 2017 and 2018. The experiment was conducted in randomized blocks with three replicates in a factorial scheme. Were collected preserved samples and amended soil layers identified by visual analysis of soil structure (0-0,16 m and 0,16 a 0,30 m) for determination of the physical and hydric attributes: particle size, mineralogy, soil bulk density (Ds), total porosity (PT), macroporosity (Ma), microporosity (Mi), air porosity (PA), field capacity (CC) and the permanent wilting point (PMP), water capacity available (CAD), as well as the hydric balance of culture in 2017 and 2018 by the sequential method of ThornthwaiteMather. The data were submitted to variance analysis (P<0.05) and tested by Tukey (p<0.05). It was possible to verify that the conservationist management system has improved the soil physical-hydric quality over time, mainly by the increase in MI (>0.47 cm3 cm-3) and PA (≥ 0.49 cm3 cm-3). In the two years evaluated the Haplustox under study provides a good amount of water availability (≥ 0.21 cm 3 cm -3 ; 81,9 mm/cm) being the precipitation the most limiting factor to crop production in the region. The best distribution of rainfall in 2018 contributed to the maintenance of soil water and better crop yield.