49 Acta herbologica, Vol. 24, No. 1, 2015. Control of Echinochloa crus-galli in Rice with Diferent POST Herbicide Treatments Zvonko Pacanoski Faculty for Agricultural Sciences and Food, Ss. Cyril and Methodius University, Skopje, R. Macedonia e-mail: zvonko_lav@yahoo.com; zvonkop@zf.ukim.edu.mk SUMMARY Te feld trials were conducted at two localities during 2013 and 2014 to evaluate diferent POST her- bicide programs for efective E. crus-galli control in rice production regions in the Republic of Mace- donia. Herbicide selectivity and infuence on grain yield were evaluated, as well. Herbicides were ap- plied in 3 POST herbicide programs: early-postemergence (EPOST), mid-postemergence (MPOST) and late-postemergence (LPOST). E. crus-galli control difered among POST herbicides, herbicide programs, and DAT. In Kočani locality E. crus-galli control across POST herbicide programs was 95 to 92% at EPOST and MPOST treatments at 14 DAT, and 99 to 98% at 28 DAT, respectively. Signif- cantly lower efcacy was provided in LPOST treatment (87% and 83%) at both estimation periods. E. crus-galli control across POST herbicide programs in Vinica locality was similar as in Kočani locality. 14 DAT efcacy was ranged between 97 and 93% at EPOST and MPOST treatments, and 28 DAT ef- cacy was ranged between 99 and 97% at same POST treatments, respectively. Signifcantly lower efca- cy was provided in LPOST treatment (82% and 81%, 14 and 28 DAT, respectively). In both localities all EPOST and MPOST applied herbicides resulted in rice yield which was not statistically diferent from rice yield in the weed-free control. Because each LPOST herbicide provided lower E. crus-galli control, and caused rice injury, there was signifcant yield reduction in all plots treated with LPOST herbicides. Key words: Echinochloa crus-galli, rice POST treatments, injury, yield UDK 632.954 Naučni rad – Scientifc paper