The presented field experiment was conducted at the Universidade Estadual de Ponta Grossa, Paraná State, Brazil, on Dark Red Latossoil, to evaluate the efficiency and selectivity of herbicides on post emergence weed control in potato crops. The experiment was laid out in a randomized block design with six treatments and four replications: propaquizafop (100, 125 and 150 g a.i/ha); fluazifop-p-butil (188 g a.i/ha), weed free and weedy. Planting was conducted on October 26, using the cultivar Elvira. Potato plants were spaced 0.70 x 0.35 m. The predominant weeds were: Brachiaria plantaginea (capim-papuã), Digitaria horizontalis (capim milhã) and Eleusine indica (capim pé-de-galinha). Evaluations were made 15, 30 and 45 days after treatment applications. Post emergent herbicie application after hilling provided suitable weed control, from emergence to harvest. The herbicide propaquizafop was efficient in control of capim-papuã and capim pé-de-galinha at 100, 125 and 150 g a.i/ha and capim-milhã using doses of 100 and 150 g a.i/ha. Production losses caused by weed competition were 57.4%. Potato plants did not show any visual symptoms of damage attributed to herbicide treatments.
Solanum tuberosum L.; chemical control
