Abstract

TIRONI, S.P. et al. Action of herbicides on the activity of phosphate-solubilizing bacteria isolated from sugarcane rhizosphere. Planta daninha [online]. 2009, vol.27, n.4, pp. 747-754. ISSN 0100-8358.  http://dx.doi.org/10.1590/S0100-83582009000400013.

The objective of this work was to evaluate the effects of herbicides on the phosphate-solubilizing activity and growth of bacteria isolated from sugarcane rhizosphere. Two bacterial isolates, Sac 4 and Sac 13, classified as being of high and low capability of solubilizing inorganic phosphate, respectively, were used in the experiments. The growth and phosphate-solubilizing activities were evaluated in the presence of trifloxysulfuron-sodium, ametryn, and trifloxysulfuron-sodium + ametryn, at 0, ½, ¾, 1, and 2 times the reference dose (0.45, 60, 0.74 + 30 mg L^-1, respectively). For Sac 4, the herbicides ametryn and trifloxysulfuron-sodium + ametryn reduced growth, with the largest reduction being observed for trifloxysulfuron-sodium + ametryn, while for Sac 13, no effect of the herbicides was observed. The phosphate-solubilizing activity of both bacterial isolates was not affected by the herbicides tested; this indicates that the impact of these compounds on the soil microorganisms is selective to certain populations.

Keywords : trifloxysulfuron-sodium; ametryn; soil microorganisms.