EFEITO DA CALAGEM NA MINERALIZAÇÃO DE 14 C-GLIFOSA TO EM SOLOS Effect of liming on the mineralization of 14 C-glyphosate in soils

Liming is a widely used soil fertility management practice and essential in tropical soils. This practice, by influencing physical, chemical and biological features of soils, may alter the behavior of organic molecules in soils. In this context, the objective of the present study was to evaluate the effect of liming on the mineralization of glyphosate in Red Latosol (LE) and Quartzarenic Neosol (RQ) soils and also on the microbial activity. The experiments were conducted in completely randomized design blocks in a 2 x 2 factorial scheme, corresponding to two soils and two management conditions (with and without liming). The radiometric technique was used to evaluate the evolution of 14 CO 2 at intervals of 7 days, during 70 days. The study of microbial activity was conducted using the methodology of radiolabelled glucose ( 14 C-glucose), which was measured at intervals of fourteen days, during 70 days. Results show that the liming increased significantly the 14 C-glyphosate mineralization and the microbial activity.