Submitted to: Proceedings of Southern Weed Science Society
Publication Type: Abstract Only
Publication Acceptance Date: 12/1/2003
Publication Date: 2/26/2004
Citation: Boyette, C.D., Hoagland, R.E. Biocontrol of Kudzu (Pueraria lobata) is synergized by glyphosate interaction. Proceedings of Southern Weed Science Society. Abstract No. 69.
Technical Abstract: Emulsified formulations of the bioherbicidal fungus Myrothecium verrucaria (Alb. & Schwein.) Ditmar:Fr. were tested alone, in combination with, prior to, and following treatment with glyphosate for control of kudzu IPueraria lobata (Willd.) Ohwii] under field conditions in naturally-infested sites near Lexington, MS in the summers of 2000 and 2001. Maximum mortality (92% and 96%, respectively) occurred 4 DAT when the fungal treatments were tank mixed or applied following glyphosate (Touchdown) treatment at recommended application rates (5 lb ai/gal). However, similar levels of control (89% and 93%, respectively) were achieved when herbicide rates were reduced to 0.1 x field rates (0.5 lb ai/gal) when used in conjunction with the bioherbicide at inoculum rates of 1 x 10**7 spores/ml. Even at 0.1x inoculum rates (1 x 10**6 spores/ml) weeds were controlled 83% and 86%. Treated weeds exhibited disease symptomatology within 12 hours following treatment. Disease symptomatology was characterized by necrotic flecking on leaves that coalesced into large lesions. Symptoms progressed from infected cotyledons and leaves to produced stem lesions within 48 h. The fungus sporulated profusely on infected tissue and was readily reisolated. These results suggest that it may be possible to use combinations of glyphosate to improve the bioherbicidal control potential and reduce herbicide and inoculum requirements of M. verrucaria for controlling kudzu.