Revista Brasileira De Herbicidas 2005; 4(3): 35-46
ISOXAFLUTOLE PERSISTENCE IN A CLAY SOIL CULTIVATED WITH POTATO
DOI: 10.7824/rbh.v4i3.35
In order to study the isoxaflutole persistence in a clay soil cultivated with potato cv. Monalisa, a field experiment was carried out at Bayer CropScience Experimental Station, in Paulínia – SP. A complete split-plot randomized block design with four replication was used. In the main plots were studied the rates 0, 75, 150 and 300 g ai/ha in a pre-emergence application. On the day of treatment and at seven day intervals until 140 days after treatment, except at 119 days, soil cores were taken from each plot. The isoxaflutole residual activity was evaluated by bioassay using bean (Phaseolus vulgaris L. cv Eté) as a test-plant. The isoxaflutole persistence of each rate was analyzed by regression analysis, with time as the independent variable and rate herbicide remaining as the dependent variable. The lost of the isoxaflutole residual activity in a clay soil was very slow. For the 75 and 150 g/ha rates, the residual period were, respectively, 84 and 112 days; it was observed recharge activity at 70 and 98 days. For the 300 g/ha rate, residual period was greater than 140 days.
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