Combination effect of ACP 2100, imazaquin and triclopyr on common dandelion and three Kentucky bluegrass turf types

The compatibility of ACP 2100, a member of the imidazolinone family (chemistry not released), imazaquin (2- [4,5-dihydro-4-methyl-4-(1-methylethyl)-5-oxo-1H̱-imidazol2- yl]-3-quinolinecarboxylic acid) and triclopyr {[(3,5,6-trichloro-2-pyridinyl)oxy]acetic acid} was investigated for use in a turf management program, including growth regulation and broadleaf weed control. Field and greenhouse results indicated an antagonistic interaction between triclopyr and imazaquin for control of common dandelion (<i>Taraxacum officinale</i> Weber in Wigger). Addition of imazaquin at 276 g ha⁻¹ to triclopyr at 138 g ha⁻¹ resulted in less dandelion control than 138 plus 138 g ha⁻¹, respectively. Greenhouse and laboratory studies indicated a synergistic interaction between ACP 2100 and triclopyr, not apparent in the field. Addition of ACP 2100 to triclopyr at 34 and 69 g ha⁻¹ resulted in less than expected dandelion biomass, indicating increased dandelion control. ACP 2100 initially decreased triclopyr uptake, but resulted in greater uptake 48 hours after treatment. ACP 2100 also increased triclopyr translocation to the crown, root and middle rosette leaves. In the field and greenhouse, triclopyr did not influence growth regulation and decreased turf injury caused by ACP 2100. Studies showed that as the rate of ACP 2100 increased with the rate of triclopyr an antagonism occurred, resulting in decreased turf injury. The low rate of both ACP 2100 and imazaquin in combination resulted in equal turf growth regulation activity to the high rate of either chemical alone or in combination. One greenhouse study indicated that the interaction was synergistic for height suppression with ACP 2100 and imazaquin at rates of 12 plus 17 or 24 g ha⁻¹, respectively. However, field studies showed that ACP 2100/imazaquin combinations resulted in unacceptable injury to ‘l90’ and ‘Glade-Plush-Ram’ Kentucky bluegrass (<i>Poa pratensis</i> L.). The best turf quality, growth regulation and dandelion control was achieved with a combination of ACP 2100 at 96 and 144 g ha⁻¹ plus triclopyr at 276 g ha⁻¹. These results indicate that turf management costs may be reduced without sacrificing dandelion control by incorporating a chemical mowing program into a spring herbicide treatment.

Name thesis:degree_name

Ph. D.

Level thesis:degree_level

doctoral

Discipline thesis:degree_discipline

Weed Science

Department dc:contributor.department

Weed Science

Grantor dc:publisher

Virginia Polytechnic Institute and State University

Year dc:date.issued

1989

Author dc:creator

• Vollmer, Jennifer Sue Landwehr

Chair dc:contributor.committeechair

• Bingham, Samuel W.

Committee members dc:contributor.committeemember

• Hall, John R.
• Hagood, Edward S.
• Hatzios, Kriton K.
• Hess, John L.

Statement dc:rights

• In Copyright

Licence dc:rights.uri

• http://rightsstatements.org/vocab/InC/1.0/

Language dc:language.iso

en_US

Handle dc:identifier.uri

http://hdl.handle.net/10919/54802

OAI identifier oai:identifier

oai:vtechworks.lib.vt.edu:10919/54802