TY - JOUR
T1 - Pool of resistance mechanisms to glyphosate in digitaria insularis
AU - De Carvalho, Leonardo Bianco
AU - Alves, Pedro Luis Da Costa Aguiar
AU - González-Torralva, Fidel
AU - Cruz-Hipolito, Hugo Enrique
AU - Rojano-Delgado, Antonia María
AU - De Prado, Rafael
AU - Gil-Humanes, Javier
AU - Barro, Francisco
AU - Luque De Castro, María Dolores
PY - 2012/1/18
Y1 - 2012/1/18
N2 - Digitaria insularis biotypes resistant to glyphosate have been detected in Brazil. Studies were carried out in controlled conditions to determine the role of absorption, translocation, metabolism, and gene mutation as mechanisms of glyphosate resistance in D. insularis. The susceptible biotype absorbed at least 12% more 14C-glyphosate up to 48 h after treatment (HAT) than resistant biotypes. High differential 14C-glyphosate translocation was observed at 12 HAT, so that >70% of the absorbed herbicide remained in the treated leaf in resistant biotypes, whereas 42% remained in the susceptible biotype at 96 HAT. Glyphosate was degraded to aminomethylphosphonic acid (AMPA), glyoxylate, and sarcosine by >90% in resistant biotypes, whereas a small amount of herbicide (up to 11%) was degraded by the susceptible biotype up to 168 HAT. Two amino acid changes were found at positions 182 and 310 in EPSPS, consisting of a proline to threonine and a tyrosine to cysteine substitution, respectively, in resistant biotypes. Therefore, absorption, translocation, metabolism, and gene mutation play an important role in the D. insularis glyphosate resistance.
AB - Digitaria insularis biotypes resistant to glyphosate have been detected in Brazil. Studies were carried out in controlled conditions to determine the role of absorption, translocation, metabolism, and gene mutation as mechanisms of glyphosate resistance in D. insularis. The susceptible biotype absorbed at least 12% more 14C-glyphosate up to 48 h after treatment (HAT) than resistant biotypes. High differential 14C-glyphosate translocation was observed at 12 HAT, so that >70% of the absorbed herbicide remained in the treated leaf in resistant biotypes, whereas 42% remained in the susceptible biotype at 96 HAT. Glyphosate was degraded to aminomethylphosphonic acid (AMPA), glyoxylate, and sarcosine by >90% in resistant biotypes, whereas a small amount of herbicide (up to 11%) was degraded by the susceptible biotype up to 168 HAT. Two amino acid changes were found at positions 182 and 310 in EPSPS, consisting of a proline to threonine and a tyrosine to cysteine substitution, respectively, in resistant biotypes. Therefore, absorption, translocation, metabolism, and gene mutation play an important role in the D. insularis glyphosate resistance.
KW - EPSPS
KW - N-phosphonomethylglycine
KW - mechanisms of resistance
KW - sourgrass
KW - weed resistance
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U2 - 10.1021/jf204089d
DO - 10.1021/jf204089d
M3 - Article
C2 - 22175446
AN - SCOPUS:84856008559
SN - 0021-8561
VL - 60
SP - 615
EP - 622
JO - Journal of agricultural and food chemistry
JF - Journal of agricultural and food chemistry
IS - 2
ER -