Revista Brasileira De Herbicidas 2018; 17(4): 1-9
Action of pre-emergence herbicides in the initial establishment of seedlings of Savana’s native species
The weed control difficulties has been considered one of the most obstacles to success of forest recovery projects at degraded areas. This experiment aimed to evaluate the different pre‑emergent herbicides effect on seed emergence, seedling survival and initial development of Brazilian native tree species Platypodium elegans, Guazuma ulmifolia, Anadenanthera colubrine and Jacaranda micrantha. The experiment was conducted under greenhouse conditions in a completely randomized design with five replications. The treatments were constituted by the pre-emergence application of the following herbicides and doses: isoxaflutole (75, 150 and 300 g a.i. ha-1), pendimenthalin (500, 1000 and 2000 g a.i. ha-1), trifluralin (600, 1200 and 2400 g a.i. ha-1) and untreated herbicide as a check control. The effect of the herbicides was evaluated for the number of seedlings emerged, number of leaves per seedlings, height of seedlings, diameter of stem and dry matter of root and leaves at 35 days after germination. With the results obtained it was possible to affirm that all herbicides and their respective rates were safe to P. elegans and G. ulmifolia trees. Isoxaflutol at 150 and 300 g a.i. ha-1 was not selective to G. ulmifolia specie. Only trifluralin at 600 and 1200 g a.i. ha-1 sowed selectivity to A. colubrina specie.
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