Dinámica de raíces finas en Eucalyptus Urophylla St. Blake con aplicación de yeso agrícola en minas gerais, Brasil.

Abstract

The study and understanding of the dynamics of the root system in plants are essential to improve silvicultural practices of forest plantations in the world, therefore, this paper seeks to establish the exploratory soil dynamics (biomass and length) of the fine roots in a population of Eucalyptus urophylla ST. Blake. (Clone I 144) with five years of age, tolerant to water deficit and with application of agricultural gypsum in Bocaiúva-MG, Brazil. The experimental design was random blocks and were evaluated two treatments: A (control without gypsum) and B (with application of agricultural gypsum), each treatment contains three blocks from which were selected three trees with the CAP closer to the average CAP of the block. The samples collection was performed using a mechanized borehole up to 4 meters deep, obtaining samples every 25 cm for the first two depths and then every 50 cm to 400 cm for a total of 9 depths (4 meters). The roots were separated from the soil by washing it thought three sieves (2, 1, and 0.5 mm in diameter) then, they were placed in glass trays for further separation by length (x ≤ 1 cm) and (x ≥ 1cm ) and by diameter (≤ 2 mm), once the roots were separated, a digital image was obtained using a scanner EPSON Perfection V700. To estimate the length and diameter was used the software WinRHIZOTM Arabidopsis, finally the roots were dried and weighed to obtain biomass. The results obtained for biomass density of fine roots show that for the A treatment the value found was 2370.34 kg ha-1 of which 44.36% (151.59 kg ha-1) corresponds to the soil between 0-25 cm and for B treatment the total value was 2,168.22 kg ha-1 of which 41.24% (894.38 kg ha-1) corresponds also to the first depth; however after applying the statistical analysis ANOVA using SAS University Edition, non significant differences between the two treatments studied (A-B) were found.