Seletividade de tembotrione aplicado em diferentes estádios fenológicos da cultura do milho safrinha

This work was developed with the objective of evaluating tembotrione selectivity to off-season maize crop, when applied on different phenological stages. The experiment was carried out on field condition, in an area at IFSULDEMINAS, Machado Campus, between March and September 2015. The corn hybrid RB9006 (Riber (R)) was sawn mechanically with density of 80.000 plants per hectare, at the depth of 0,05 m, in no-tillage system. Experimental design of randomized blocks was adopted, with five treatments and five replicates. Plots consisted of six rows of corn crop, with five meters of length. Respecting phenological stages, tembotrione herbicide was applied at 100.8 g ha(-1), with vegetal oil at 0.5 % v/v. Applications were achieved on the corn crop at V2, V4, V7 and V10 stages, besides hand weeded check plots without application. All the plots were hand weeded permanently during all the trial. Mean yield of the area was 7,010 kg ha(-1), and it was considered perfectly satisfactory for off-season crop condition. Visual injuries were not observed on the corn crop, in any of the phenological stages. Significance of the treatments was not observed for any variable (grains per row, rows per ear, cob diameter, mass of 1,000 grains and productivity). Therefore, tembotrione was considered perfectly selective to the off-season corn at the recommended rate.