Controle de amarelinho (Tecoma stans) em pastagem com aplicações localizadas de herbicidas

Abstract

Controle de amarelinho (TecomaAbstract -The presence of yellow bells (Tecoma stans) in pastures can compromise the implantation and the development of forage, damaging animal production and hindering mechanized operations with trailing implements. The objective of this paper was to evaluate the yellow bells control after localized herbicides applications and the fitointoxication of pasture composed of Urochloa maxima (syn Panicum maximum). The treatments were triclopyr (4%) and triclopyr (3%) applied to the stump base (SB); picloram (2%) applied on stump after plants (SA); triclopyr + picloram (1% + 1%) and triclopyr + picloram (2% + 2%) SB; plus a check without herbicide application and a check where plants were mowed. All herbicides treatments resulted over 95% control 270 days after application and were more efficient than stump cut treatment, which showed capacity of regrowth. The herbicides promoted injures on pasture, however the symptoms were observed only in the area located around the T. stans plants.

Altura de roçada afeta o controle de capim-amargoso perenizado

“…Para o controle de plantas daninhas arbóreas em pastagens, a aplicação de herbicida sistêmicos no caule imediatamente após o corte da parte aérea proporciona a translocação dos herbicidas pelo floema (MENDES et al, 2016). Todavia, a aplicação nos restos culturais do capim-amargoso após a roçada não suprimiu o rebrote das plantas, provavelmente pela limitada absorção e translocação dos herbicidas pelos colmos e raízes.…”

“…Existem possibilidades de diferentes alturas de roçada influenciarem o controle de capim-amargoso quando associados ao controle químico. Em pastagens, é comum o corte das plantas seguido de aplicação de herbicidas diretamente no toco em espécies arbóreas (MENDES et al, 2016). Apesar de não avaliado em gramíneas, pode haver absorção e translocação dos herbicidas aplicados logo após a roçada, de modo a intoxicar as estruturas vegetativas abaixo do solo para evitar novos rebrotes.…”

Pasture weed biology and management in Brazil

“…Regarding the effectiveness of the chemical control of weeds in pastures, some studies mention the use of several herbicides in an attempt to control species, such as yellow elder (Passini & Kranz, 1997;Mendes et al, 2016), Brachiaria grass (W. Silva, Vilela, Pereira, Ferreira, & Ferreira, 2002; M. V. Santos et al, 2006), Acacia farnesiana (Willd. ), Mimosa pteridophyte (Mart.)…”

“…plant-1) evaluated was efficient to control the plants within 9 months after application. Mendes et al (2016) also studied yellow elder control (T. stans) in the pasture, with localized applications of the herbicides triclopyr (4%) and triclopyr (3%), applied at the base of the plants; picloram (2%), applied to the stump of the plants after cutting; and triclopyr + picloram (1% + 1%) and triclopyr + picloram (2% + 2%), applied at the base of the plants, and found that all herbicides provided control levels above 95% at 270 d after application, being more efficient than the treatment with shoot cutting because of the re-growth capacity of the plants. The researchers added that the herbicides damaged the pasture in the area immediately around the plants that received the application.…”

Glyphosate-Resistant Sourgrass Management Programs Associating Mowing and Herbicides

“…The hypothesis of improved control by herbicide application immediately after mowing is related to the eventual herbicide absorption and translocation through culms and remaining leaves. This type of practice is usual for weed control in pastures by cut-stump herbicide applications (Mendes et al, 2016). However, the most common weeds in pastures are dicotyledonous species, either herbaceous plants or woody shrubs.…”