Fusarium sp. (isolation FCAV#940) has potential for the biological control of the macrophytas Egeria najas and Egeria densa, plants that cause losses of several kinds in water bodies. This study evaluated the likelihood of associating the fungus to concentrations of herbicides to optimize weed control, by measuring the inhibitory effects of several concentrations of herbicides on Fusarium sp. mycelial growth, sporulation and spore germination. The herbicide concentrations analyzed were: ½, 1.0 and 2.0 the concentration recommended by the manufacturer. Since these aquatic weeds are submerged, a diluted concentration in 15cm water depth was considered. The herbicides and concentrations (a.i.) evaluated were: triclopyr at 6.0; 3.0 and 1.5 mg L-1; glyphosate at 6.87; 3.44 and 1.72 mg L-1 ; 2.4-D at 8.54; 4.27 and 2.14 mg L-1 ; diquat at 2.0; 1.0 and 0.5 mg L-1 ; fluridone at 200; 100 and 50 µg L-1 ; and a control (non-amended PDA). The results indicated that the herbicides at the tested concentrations did not inhibit Fusarium sp. mycelial growth, macroconidia production or germination.
mycelial growth; sporulation; germination; fungus; inhibition
