02022naa a2200325 a 450000100080000000500110000800800410001910000170006024500800007726000090015730000200016649000080018652011560019465000110135065000210136165000220138265000130140465000140141765300140143165300110144565300150145665300140147165300190148565300180150465300180152265300220154065300140156265300090157677301110158514523822004-10-28       1985    bl uuuu     u00u1 u    #d1 aFLECK, N. G.  aEvaluation of pre-emergence herbicides and their combinations in sunflower.  c1985  a p.497-502. t.2  vt.2  aDuring the 1983/84 growing season it was conducted a field experiment in Guaiba, RS, Brazil, in order to evaluate the efficiency of pre-emergence herbicides and their combinations for weed control in sunflower. The herbicide treatments evaluated were 2-chloro-2', 6-diethyl-N-(methoxymethyl) acetanilide (alachlor; 3600 g/ha), 3-amino-2,5-dichlorobenzoic acid (chloramben; 2250 g/ha), 3-(3,4-dichlorophenyl)-1-methoxy-1-methylurea (linuron; 750 g/ha), 2-chloro-N-(2-ethyl-6-methylphenyl)-N-(2methoxy-1-methylethyl)-acetamide (metolachlor; 2160 g/ha), and 2,4-bis(isopropylamino)-6-(methylthio)-s-triazine (prometryn; 1920 g/ha) and also the combinations of alachlor or metolachlor with chloramben, linuron or  prometryn, when the rates were reduced by 1/3 of thoseapplied individually. The most efficient herbicide treatment, equivalent to the weed-free check, was the combination of metolachlor + prometryn; however, it did not differ from alachlor + prometryn, alachlor + chloramben, and alachlor alone. Linuron, prometryn, and chloramben were the treatments that presented the lowest herbicide efficiency due to their defficient grass weed control.  aBrazil  achemical control  aControle Químico  aGirassol  aHerbicida  aAvaliacao  aBrasil  aEvaluation  aHerbicide  aPlanta daninha  aPre-emergence  aPre-emergente  aRio Grande do Sul  aSunflower  aWeed  tIn: CONFERENCIA INTERNACIONAL DE GIRASOL, 11., 1985. Mar del Plata. Actas. Mar del Plata:ASAGIR/ISA, 1985.