How to translate text using browser tools
1 April 2011 Anatomical Response of St. Augustinegrass to Aminocyclopyrachlor Treatment
Michael L Flessner, Roland R Dute, J. Scott McElroy
Author Affiliations +

Aminocyclopyrachlor (AMCP) is a synthetic auxin herbicide that controls primarily broadleaf (eudicotyledonous) weeds. Previous research indicates that St. Augustinegrass is unacceptably injured by AMCP. In light of the fact that synthetic auxin herbicides usually are safe when applied to monocotyledons, the mechanism for this injury is not fully understood. Anatomical response of St. Augustinegrass to AMCP was investigated using light microscopy. Apical meristem node tissue responded with callus tissue proliferation, abnormal location and development of the apical meristem, necrosis of the developing vascular tissue, vascular parenchyma proliferation, and xylem gum blockages. Node tissues away from the apical meristem responded with xylem gum blockages and the stimulation of lateral meristems and adventitious root formation. Root tip response to AMCP treatment was characterized by a loss of organization. Root tip apical meristem and vascular tissue maturation was disorganized. Additionally, lateral root generation occurred abnormally close to the root tip. These responses impair affected tissue functionality. Mature tissue was unaffected by AMCP treatment. All of these responses are characteristic of synthetic auxin herbicide treatment to other susceptible species. This research indicates that AMCP treatment results in St. Augustinegrass injury and subsequent death through deleterious growth stimulation and concomitant vascular inhibition.

Nomenclature: Aminocyclopyrachlor, DPX-KJM44, DPX-MAT28; St. Augustinegrass, Stenotaphrum secundatum (Walter) Kuntz ‘Palmetto’®, STPSE

Weed Science Society of America
Michael L Flessner, Roland R Dute, and J. Scott McElroy "Anatomical Response of St. Augustinegrass to Aminocyclopyrachlor Treatment," Weed Science 59(2), 263-269, (1 April 2011).
Received: 5 August 2010; Accepted: 1 December 2010; Published: 1 April 2011
Synthetic auxin herbicide
Get copyright permission
Back to Top