TY - JOUR
T1 - Nozzle selection and adjuvant impact on the efficacy of glyphosate and PPO-inhibiting herbicide tank-mixtures
AU - Moraes, Jesaelen G.
AU - Butts, Thomas R.
AU - Anunciato, Vitor M.
AU - Luck, Joe D.
AU - Hoffmann, Wesley C.
AU - Antuniassi, Ulisses R.
AU - Kruger, Greg R.
N1 - Funding Information:
Funding: This project is based on research that was partially supported by the Nebraska Agricultural Experiment Station with funding from the Hatch Multistate Research capacity funding program from the USDA National Institute of Food and Agriculture.
Publisher Copyright:
© 2021 by the authors. Licensee MDPI, Basel, Switzerland.
PY - 2021/4
Y1 - 2021/4
N2 - PPO-inhibiting herbicides in combination with glyphosate for postemergence applications is a common approach to manage glyphosate-and ALS-inhibitor-resistant weeds. PPO-inhibitors can reduce glyphosate translocation when applied in tank-mixtures, but adjuvants may be used to overcome this effect. Additionally, optimal droplet size may be affected by tank-mixtures of different herbicides and it can be crucial to herbicide efficacy. Field and greenhouse studies were conducted to investigate the impact of nozzle selection and adjuvants on weed control and interactions when applying PPO-inhibitors (fomesafen or lactofen) alone or in tank-mixture with glyphosate to five weed species using six nozzle types. Ultra-coarse droplets were just as effective as medium droplets regardless of the spray solution, but have a lower likelihood of off-target movement. Tank-mixtures applied were consistently antagonistic to common lambsquarters, horseweed, and Palmer amaranth. Only fomesafen was antagonistic to kochia whereas synergistic interactions were observed when glyphosate plus lactofen were applied in combination with COC, DRA + COC, or NIS. Separate applications are advisable with herbicide-and weed-specific situations to avoid antagonism, which is necessary to achieve optimum weed control and maintain the effectiveness of PPO-inhibitors. Future research should continue to look at these important interactions across a wide range of weed species.
AB - PPO-inhibiting herbicides in combination with glyphosate for postemergence applications is a common approach to manage glyphosate-and ALS-inhibitor-resistant weeds. PPO-inhibitors can reduce glyphosate translocation when applied in tank-mixtures, but adjuvants may be used to overcome this effect. Additionally, optimal droplet size may be affected by tank-mixtures of different herbicides and it can be crucial to herbicide efficacy. Field and greenhouse studies were conducted to investigate the impact of nozzle selection and adjuvants on weed control and interactions when applying PPO-inhibitors (fomesafen or lactofen) alone or in tank-mixture with glyphosate to five weed species using six nozzle types. Ultra-coarse droplets were just as effective as medium droplets regardless of the spray solution, but have a lower likelihood of off-target movement. Tank-mixtures applied were consistently antagonistic to common lambsquarters, horseweed, and Palmer amaranth. Only fomesafen was antagonistic to kochia whereas synergistic interactions were observed when glyphosate plus lactofen were applied in combination with COC, DRA + COC, or NIS. Separate applications are advisable with herbicide-and weed-specific situations to avoid antagonism, which is necessary to achieve optimum weed control and maintain the effectiveness of PPO-inhibitors. Future research should continue to look at these important interactions across a wide range of weed species.
KW - Air inclusion nozzle
KW - Crop oil concentrate
KW - Drift reducing adjuvant
KW - Methylated seed oil
KW - Non-air inclusion nozzle
KW - Non-ionic surfactant
KW - Soybeans
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U2 - 10.3390/agronomy11040754
DO - 10.3390/agronomy11040754
M3 - Article
AN - SCOPUS:85108714409
SN - 2073-4395
VL - 11
JO - Agronomy
JF - Agronomy
IS - 4
M1 - 754
ER -