Portal de Periódicos da CAPES

Control of volunteer glyphosate-tolerant maize (Zea mays) in glyphosate-tolerant soybean (Glycine max)

2005; Elsevier BV; Volume: 25; Issue: 2 Linguagem: Inglês

10.1016/j.cropro.2005.03.017

1873-6904

Nader Soltani, Christy Shropshire, Peter H. Sikkema,

Soybean genetics and cultivation

Glyphosate-tolerant volunteer maize (Zea mays L.) has become a problem when glyphosate-tolerant soybean [Glycine max (L.) Merr.] follows glyphosate-tolerant maize in a crop rotation. A total of four field trials were conducted at Exeter, Ontario over a 2-year period (2003 and 2004) to evaluate the control of glyphosate-tolerant volunteer maize in glyphosate-tolerant soybean. Treatments consisted of postemergence (POST) glyphosate at 900 g ae/ha alone (control) and in tank-mix with clethodim (at 15, 22.5 and 30 g ai/ha), fenoxaprop-p-ethyl (at 27, 40.5 and 54 g ai/ha), fluazifop-p-butyl (at 37.5, 56.2 and 75 g ai/ha), quizalofop-p-ethyl (at 18, 27 and 36 g ai/ha), or sethoxydim (at 75, 112.5 and 150 g ai/ha). Glyphosate tank-mixed with clethodim, fenoxaprop-p-ethyl, fluazifop-p-butyl, quizalofop-p-ethyl, and sethoxydim did not injure the soybean and controlled volunteer maize. Glyphosate-tolerant volunteer maize density and dry weight were reduced with clethodim, fenoxaprop-p-ethyl, fluazifop-p-butyl, quizalofop-p-ethyl, and sethoxydim, but sethoxydim did not provide control of glyphosate-tolerant volunteer maize equivalent to the other herbicides evaluated. There was a decrease in control as the dose of clethodim, fenoxaprop-p-ethyl, fluazifop-p-butyl, and sethoxydim were reduced. There was no dose response with quizalofop-p-ethyl. Soybean yields closely reflected the level of glyphosate-tolerant volunteer maize control achieved. Based on these results, clethodim, fenoxaprop-p-ethyl, fluazifop-p-butyl, and quizalofop-p-ethyl at the recommended dose can be used to effectively control glyphosate-tolerant volunteer maize in glyphosate-tolerant soybean under Ontario growing conditions.