Skip to main content
ARS Home » Midwest Area » Columbia, Missouri » Cropping Systems and Water Quality Research » Research » Publications at this Location » Publication #349946

Research Project: Long-term Management of Water Resources in the Central Mississippi River Basin

Location: Cropping Systems and Water Quality Research

Title: Evaluating the potential utility of switchgrass (Panicum virgatum) for phytoremediation of herbicides

item HATCH, K - University Of Missouri
item Lerch, Robert
item GOYNE, K - University Of Missouri
item WILLETT, C - University Of Arkansas
item KREMER, R - University Of Missouri
item ROBERTS, C - University Of Missouri

Submitted to: International Soil and Water Conservation Conference
Publication Type: Abstract Only
Publication Acceptance Date: 3/31/2018
Publication Date: N/A
Citation: N/A

Interpretive Summary:

Technical Abstract: Herbicide contamination of soil and water can pose a variety of human health risks. However, the use of vegetative filter strips (VFS) can significantly decrease the amount of herbicides entering surface waters through runoff. Strategic implementation of specific grass species within VFS may further enhance degradation of herbicides preventing water contamination. Eastern gamagrass (Tripsacum dactyloides), has been shown to produce benzoxazinone (Bx) compounds that enhance degradation of the herbicide atrazine. Additionally, the more versatile switchgrass (Panicum virgatum) can also enhance atrazine degradation in soil, but the atrazine degrading phytochemical(s) is unknown. The objectives of this research are to: (1) identify switchgrass varieties capable of producing phytochemicals that degrade atrazine; (2) identify the phytochemicals responsible for enhanced atrazine degradation; and (3) evaluate the efficacy of these switchgrass varieties under field conditions. Root extracts from eight varieties of switchgrass were reacted with atrazine dissolved in 25% methanol for 16 hours. Atrazine remaining in the reaction vessels was quantified using High Performance Liquid Chromatography (HPLC) with a diode array detector (DAD). Least squares ANOVA was used to compare atrazine concentrations in samples containing root extract+atrazine and control samples (atrazine, only). Three switchgrass varieties degraded between 79% and 85% of atrazine compared to control values. Field experiments will compare atrazine degradation in replicated plots of three varieties of switchgrass; one variety of eastern gamagrass; and bare soil control plots. Final results of this work will identify the phytochemicals in switchgrass responsible for atrazine degradation as well as specific plants for use in VFS where atrazine is commonly applied.