Open AccessINFLUENCE OF VARIOUS HERBICIDES AND TWEEN 20 ON THE EFFECTIVENESS OF GLYPHOSATE
Author(s) -
P. A. O’Sullivan,
John T. O’Donovan
Publication year - 1980
Publication title -
canadian journal of plant science/canadian journal of plant science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.338
H-Index - 59
eISSN - 1918-1833
pISSN - 0008-4220
DOI - 10.4141/cjps80-137
Subject(s) - glyphosate , dicamba , bromoxynil , mcpa , avena , agronomy , hordeum vulgare , mecoprop , biology , glycine , weed control , chemistry , poaceae , biochemistry , amino acid
Glyphosate (N-phosphonomethyl glycine) at 0.21 kg/ha applied at the 4-leaf stage provided excellent control of wheat (Triticum aestivum L.), barley (Hordeum vulgare L.), oats (Avena sativa L.), and rape (Brassica campestris L.). Tank mixtures of 0.21 kg/ha glyphosate with bromoxynil/MCPA, bromoxynil, MCPA, 2,4-D, or dicamba resulted in an initial reduction (antagonism) of glyphosate activity on the grass species at 5 days after treatment. At 34 days after treatment, the early differences had disappeared and grass kill was virtually complete with all treatments containing glyphosate. The early reduction in annual grass control with these mixtures was overcome in most cases by addition of Tween 20. Dicamba at 0.11 kg/ha, applied sequentially at various times in relation to glyphosate at 0.21 kg/ha, provided significantly increased early control of annual grasses over that obtained with glyphosate alone. Glyphosate combinations with bromoxynil/MCPA, bromoxynil, MCPA, 2,4-D, or dicamba were as effective or more effective for rape control than the various broad-leaved herbicides applied alone. Rape showed a high degree of tolerance to dicamba.