The 'Group' letters/numbers that you see throughout this web site refer to the classification of herbicides by their site of action. To see a full list of herbicides and HRAC herbicide classifications click here.
QUIK STATS (last updated Jan 20, 2015 )
NOTES ABOUT THIS BIOTYPE
DETERMINACIÓN DE RESISTENCIA A GLIFOSATO EN UN BIOTIPO DE Digitaria insularis DEL SUR DE LA PROVINCIA DE SANTA FE (ARGENTINA)
Martín Marzetti1, Matías Bertolotto2, Pablo Lopez Anido3, Mauro Passarini4, Alejandro Iturbe5 1AAPRESID, Dorrego 1639, Rosario. firstname.lastname@example.org 2AAPRESID, Dorrego 1639, Rosario. email@example.com 3AAPRESID, Dorrego 1639, Rosario. firstname.lastname@example.org 4INDEAR, Ocampo 210 bis, Rosario. email@example.com 5INDEAR, Ocampo 210 bis, Rosario. firstname.lastname@example.org
SUMMARY Resistant weeds are a growing problem in productive systems around the world. In 2014 a Digitaria insularis biotype suspected of glyphosate resistance was identified in La Ribera (south of Santa Fe Province, Argentina). Level of glyphosate resistance was evaluated through a dose-response experiment of the suspected biotype and a susceptible D. Insularis biotype. The level of glyphosate resistance of the suspected biotype was higher than the ones registered in other countries in populations of this species.
Laboratory trials to determine Eleusine indica resistance in Tucumán (Argentina)
Experiments were conducted at the University of Tucumán (Lat. 26° 50’ S; Long 65º 16' O) Argentina in 2012 to compare a known susceptible Eleusine indica biotype with a new biotype to confirm resistance. Seven different rates (0; 1/16 X; 1/8 X; ¼ X; ½ X; X; 2X), being X 750 g a.e. glyphosate/ha. Four replicates (pots with 10 plants each) were used.
Glyphosate applications were made with CO2 backpack sprayer. Spray solutions were delivered through 8003 flat-fan nozzles at 187 L ha-1 and a pressure of 270 kPa.
Biomass at 21 days after application was determined
The relationships between glyphosate rate and biomass. For the susceptible and the resistance biotypes fitted to a log-logistic model (Seefeldt et al., 1995). The glyphosate rate causing the 50% reduction in biomass for the susceptible biotype was 375 g a.e./ha and for the resistant biotype 750 a.e./ha
Results indicate that Resistance Index is 1.98.
CONTRIBUTING WEED SCIENTISTS