Revista Brasileira De Herbicidas 2013; 12(3): 210-219

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Potencialization of mesotrione efficiency in tank mixture with inhibiting of Photosystem II by distinct absorption pathways of crabgrass

DOI: 10.7824/rbh.v12i3.257

With the objective of evaluating the potencialization efficiency of mesotrione in tank mixture with inhibitors Photosystem II in Digitaria horizontalis control, four experiments were conducted in plastic greenhouses belonging to Superior School of Agronomy of Paraguaçu Paulista County, São Paulo State, being used a Latosoil with sandy texture. The experimental design of four experiments was entirely randomized, with 10 treatments and 5 replications, in factorial scheme 3×3+1, being considered the contrast between mesotrione (96 g ha-1) and inhibitors of the Photosystem II herbicide (ametryn, 1500 g ha-1; metribuzin, 1440 g ha-1; diuron + hexazinone, 936+264 g ha-1 and atrazine, 2000 g ha-1) products, isolated and in tank mixture for three absorption conditions and a check. The absorption conditions were constituted by the isolation and/or partial exhibition of target seedling of D. horizontalis (3 to 6 leaves) in relation to deposition of pulverizations for the modalities: a) seedlings protected with plastic tubes in discovered soil (root absorption pathway); (b) unprotected seedlings in soil covered with aluminum sheet (leaf absorption pathway); (c) seedlings and soil submitted to deposition of the herbicides (absorption roots + leaves pathways) and (d) check. The largest synergism levels obtained for D. horizontalis control were registered to root absorption and leaf + root of the tank mixture with mesotrione + atrazine, as well as for leaf absorption and leaf + root of mesotrione + diuron + hexazinone from the 3 to the 7 DAA (days after application) and of mesotrione + ametryn starting from 7 DAA, both characterized by reduction of control initial time in reaching great levels (≥ 90%). Antagonistic effects were not verified for the tank mixtures.