Light availability interferes with absorption and translocation of 14C-glyphosate in Urochloa brizantha cv. Marandu plants

Control of Urochloa brizantha cv. Marandu by Glyphosate and its Interaction with light availability

“…If the sugars are not being produced and transported, the transport in phloem is decreased and, consequently, the herbicide does not translocate in the plant, becoming concentrated in the leaves (ROMAN et al, 2007). Thus, the results found indicate that the difference in the level of injury up to 21 DAA between treatments may have been due to changes in absorption and translocation.Added to this, because the leaves of U. brizantha are densely hairy, it makes it difficult to absorb the herbicide by cuticle and also by the low octanol content-water partition coefficient (log Kow) (~ −4) of glyphosate compared to other herbicides (CASTRO et al, 2016;MOTA et al, 2020). Dry matter evaluations showed that in all luminosity conditions there was an effective reduction of U. plants, with a total absence of regrowth at the highest doses (1,440 and 2,160g ha -1 ) and a reduction of more than 80% from the dose 720 g ha -1 of glyphosate (Figure 2).…”