Interferência de plantas daninhas no estabelecimento do trevo branco como cultura forrageira

White clover tolerance to herbicides applied at different rates and phenological stages

“…According to Schuster et al (2013), sow thistle (Sonchus oleraceus), wild radish (Raphanus raphanistrum), ragweed (Ambrosia elatior), sticky nightshade (Solanum sisymbriifolium), bristly starbur (Acanthospermum hispidum) and arrowleaf sida (Sida rhombifolia) are the most important weed species on white clover fields in southern Brazil. Therefore, 2.4-D stands as a good alternative due to its control efficacy over these weeds.…”

“…Moreover, it is important to emphasize that this growth reduction and lower dry matter accumulation may over time be recovered once weeds are controlled. On the other hand, if weed control is not performed, losses can reach as high as 96%, practically making it impossible for grower to cultivate this species (Schuster et al, 2013).…”

“…In many cases, weeds are a major problem *Corresponding author. E-mail: pauloadami@utfpr.edu.br Author(s) agree that this article remain permanently open access under the terms of the Creative Commons Attribution License 4.0 International License limiting white clover establishment (Rolston and Archie, 1999;Schuster et al, 2013).…”

“…Despite the fact that herbicide tolerance is the basis for the success of chemical weed control, the results available on white clover tolerance to herbicides are controversial given that some authors have reported that yield and persistence of the legume were markedly reduced (Griffin et al, 1984;Evers et al, 1993), whereas others have shown that although some herbicides can have initial phytotoxic effects, seedlings usually recover without severe damage (Machado et al, 2013) Selective post emergence herbicides are needed as emerging clover seedlings development is slow and not competitive with faster growing weeds (Schuster et al, 2013). Moreover, on crop livestock farms, corn may be cultivated using clover as living mulch or over its dead biomass, however, herbicide tolerance needs to be known for improved clover management.…”

“…meristematic tissues (Evers et al, 1993). Schuster et al (2013) while evaluating weed interference in white clover, reported that the critical period of interference occurred between 20 th and 62 nd days after emergence. Rolston and Archie (1999) also reported that phenological stage affected cultivar sensitivity to the herbicide diflufenican.…”