Redvine (Brunnichia ovata) and trumpetcreeper (Campsis radicans) controlled under field conditions by a synergistic interaction of the bioherbicide, Myrothecium verrucaria, with glyphosate.
In field experiments conducted near Stoneville, MS, USA, in 2000 and 2001, the bioherbicidal fungus, Myrothecium verrucaria (Alb. & Schwein.) Ditmar: Fr., was tested alone and in combination with a glyphosate (N-[phosphonomethyl]glycine) product for controlling natural infestations of the invasive vines, redvine (Brunnichia ovata [Walt.] Shinners) and trumpetcreeper (Campsis radicans [L.] Seem. ex Bureau). After 12 days, redvine and trumpetcreeper were controlled by 88% and 90%, respectively, through a synergistic interaction between the fungus and the herbicide, glyphosate. The disease symptomatology was characterized by rapid necrosis of the leaf and stem tissues, with mortality occurring within 72 h. Neither glyphosate alone, nor M. verrucaria alone, controlled these weeds at commercially acceptable levels (≥80%). No visual disease or herbicide damage occurred to the soybean in the treated test plots 12 days after planting. These results suggest that some formulations of glyphosate, mixed with M. verrucaria, can effectively control redvine and trumpetcreeper.