Efeito da adubação verde na estabilidade de agregados de um solo sob cultivo de hortaliças orgânicas na região de capim branco - mg

The use of green manure provides organic matter to the soil, which improves its physical conditions due to the fact that it is the main cementing agent that forms the soil aggregates.This study aimed to evaluate the stability of soil aggregates in areas of organic farming at different times of use of green manure, in Capim Branco/MG, in order to investigate if there is a soil improvement regarding its physical quality.Four treatments were studied: newly scuffed green manure (T1); cultivation of organic vegetables in which had been cultivated green manure a year ago in the area (T2); cultivation of organic vegetables in which had been cultivated green manure for three years in the area (T3); and cultivation of organic vegetables in which had never been grown green manure before (T4).The samples were collected at 0-10 and 10-20 cm in five replicates.The analysis of aggregate stability was performed, to determine the mean weight diameter (MWD) and the geometric mean diameter (GMD).This study also determined the flocculation ind ex (IF), through the evaluation of water dispersible clay (WDC) and soil particle size characterization.The statistical design was completely randomized.Data were subjected to analysis of variance, and means were compared using the Scott-Knott test at 5 % of probability.There were no significant differences (p<0,05) for aggregate diameter classes, nor MWD and GMD.The use of the green manure by producers in Capim Branco/MG, does not promote structural changes in the soil, since the use of this practice is not continuous throughout the crop cycle.