Selectivity of the herbicide linuron sprayed in pre-emergence and post-early in carrot

Abstract

Herbicide application is a method for weed control in carrot crops. However, the choice of the chemical treatment (herbicide, association of products, dose, and time of application) should consider its selectivity to the crop. It is desired to analyze the selectivity of linuron for carrot plants, when sprayed on pre-emergence and post-early cultivated plants. Two experiments were carried out in the field in an area of the commercial production of carrots, one with the Verano cultivar and the other with BRS Planalto. Both experiments included an experimental design with randomized blocks in a factorial 2 x 4 + 1 with six and four replications for the experiments with Verano and BRS Planalto, respectively. The herbicide linuron (675 and 990 g a.i. ha-1) was sprayed at four times, counting from the carrot sowing day: in the pre-emergence of the crop at 0, 3, and 6 days after sowing (DAS) and in the post-early emergence at 9 DAS, when the plants had 1 or 2 cotyledons. An untreated control was maintained as an additional treatment. Linuron was selective for the carrot plant cultivars Verano and BRS Planalto, in both doses tested, when sprayed in the pre-emergence, up to six days after sowing, and in the post-early (plants with 1 or 2 cotyledon leaves) at nine days after sowing.