Chemical Weed Control with Sulfometuron in Apple Orchard

Two year field studies were conducted to determine efficiency of sulfometuron for weed control in apple orchard.Pre-emergence application of sulfometuron at 0.015 kg/hm2 provided good weed control one month after treatment.The term of effective control lasted for 70 days when sulfometuron was applied at 0.025,0.045 and 0.09 kg/hm2,control efficiency was 85.5%～100%.But above treatment had poor control to pernual weed,only 12.0%～68.0%.Post-emergence application of sulfometuron at 0.060 and 0.090 kg/hm2 gave significant suppress of weeds 40 days after treatment and the suppressing level of plant height and weight were 75%～85% and 78.2%～90.0%,respectively.Sulfometuron plusing diuron(1.20 kg/hm2),armzine(1.20 kg/hm2)or glyphosate(0.30 kg/hm2)improved the level of weed control compared with sulfometuron post-emergence used alone.All treatments had no bad effect on the growth of apple tree compared with the check.