Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 9/16/2011
Publication Date: N/A
Citation: N/A Interpretive Summary: Abstract Only - Interpretative Summary not required.
Technical Abstract: Glyphosate is one of the most widely applied herbicides globally. While extensive research exists on the effects of glyphosate on non-target species exposed via drift and by-spray, little work has been done investigating the effects of root-zone glyphosate exposure that is associated with runoff from agricultural fields. The objective of this experiment was to determine the lethal and sublethal concentrations of glyphosate for two ruderal species commonly found in agricultural ditches, Panicum hemitomon and Polygonum hydropiperoides, when exposed to glyphosate in the root-zone. Glyphosate solution (100 mL) was introduced to the top of the potting substrate (sand) of individual plants in concentrations of 0, 10, 1000, 10000 mg L-1. All plants of P. hemitomon and P. hydropiperoides displayed 100% mortality within 7 days of exposure to 10000 mg L-1. All P.hemitomon plants survived (0% mortality) at lower concentration exposures, while P. hydropiperoides had higher rates of mortality for concentrations of 10 and 1000 mg L-1 (17% and 100%, respectively). The results of this experiment allow for further experimentation utilizing sublethal root-zone glyphosate concentrations to further understand the physiological and morphological effects of such exposures on ditch species and their functioning.