Study of 2,4-DB efficacy for broad leaf weed control in new seeded and established Alfalfa (Medicago sativa L.)

In this study the efficacy of Butress (2,4-DB 42.3%EC) in weed control of Alfalfa was compared with common herbicides in alfalfa. This experiment was conducted in Karaj, Hamedan, and Yazd durng 1386-1387 in a randomized complete block design with 3 replications and 11 treatments in new seeded and established alfalfa. Treatments were included Bentazone (Bazagran) (SL 48%) 2, 3, and 4 lit/ha, 2,4-DB (Butyracee) (EC 42.3%) 2.5, 2.8, 3.1, and 3.5 lit/ha, Imazethapyr (Pursuit) (SL 1%) 0.4, 0.7, and 1 lit/ha and without herbicide control treatment.The herbicides effect on alfalfa biomass and the biomass and density of weeds was studied. The effect of new seeded Alfalfa in Yazd showed that Butress 3.5 L/ha was the treartment in increase in Alfalfa biomass. Butress 3.5 and 2.8 L/ha controled the density and biomass of Malva and Lactuca to 100 and 88 percent. The effect of established Alfalfa in Yazd showed that Butress 3.5 and 2.8 and Persuit 0.4 L/ha caused increase in Alfalfa biomass. All of Butress doses controled the density and biomass of Malva and Lactuca to 100 and field bindweed to 84 percent. In Hamedan, all herbicides treatments had no phytotoxocity on Alfalfa. Only Basagran caused chlorosis in Alfalfa that recovered that after 1 to 2 weeks. Butress not only was suitable in control of weeds, but also was successful in field bindweed control. In Karaj, Butress was the best herbicide in increasing of Alfalfa biomass and weed control, especially ib the first harvesting. In other harvesting, ite effect was similar to apaersuit. Overall. Butress was the best herbicide in the control of field bindweed and it seems to be a efficient herbicide.