02166naa a2200229 a 450000100080000000500110000800800410001910000140006024500810007426000090015530000210016449000080018552015410019365000110173465000160174565000090176165300110177065300190178165300120180065300090181277301150182114512642004-10-26       1989    bl uuuu     u00u1 u    #d1 aALVES, A.  aWeed management and control in soybeans (Glycine max [L.] Merril) in Brazil.  c1989  ap.2369-2388. t.5  vt.5  aSoybean crop production is one of the most important activities in the Brazilian agriculture. The planted area was 10,559,723 ha and was expected grain production of 20,004,781 tons in 1987-1988. The major producer states are Rio Grande do Sul (32.54%), Parana (20.07%), Mato Grosso do Sul (11.13%), Mato Grosso (12.62%). Management and controlling of the weeds are achieved by various methods as cultivation, cultural practices and chemicals to control weeds. "No till" is a crop production system that is used in the south region of the country, totaling an area of 631,500 ha. The most common annual and perennial weeds to this crop, biological caracteristics and the period of weed competition are indicated. The most thoublesome annual weeds are: spurge (Euphorbiaheterophylla L.), starbur bristtly (Achanthospermum hispidum DC.), starbur paraguay (Acanthospermum australe (Loefl O. Kuntze), sicklepod (Cassia spp.), beggarweed (Desmodium spp.) and nightshade, sticky (Solanum spp.). From the total planted area, 53% is treated with chemicals. Trifluralin is the most used product applied at PPI to control annual grasses and some broadleaf weeds (89,7%), followed by sethoxydim, metolachlor and fluazifop-butyl  (10.3%). Broadleaf weeds that control herbicides are less used (27.8%), standing out in this case imazaquin, metribuzin, alachlor and cyanazine for pre-emergence application, and bentazon, fomesafen, lactofen and chlorimuron-ethyl at post-emergence application. The most common herbicides and mixtures used in this ...  aBrazil  aGlycine Max  aSoja  aBrasil  aPlanta daninha  aSoybean  aWeed  tIn: CONFERENCIA MUNDIAL DE INVESTIGACION EN SOJA, 4., 1989, Buenos Aires. Actas... Buenos Aires: AASOJA, 1989.