Abstract Detail

Ecological Section

Ahrens, Collin [1], Ecker, Geoffrey [2], Auer, Carol [1].

Research on plant community assemblage for Agrostis supports ecological risk assessment for genetically engineered Agrostis stolonifera.

Agrostis stolonifera is a perennial, ruderal species that is part of a hybridizing complex referred to as bentgrasses. Potential commercialization of genetically-engineered herbicide-resistant (HR) A. stolonifera for golf course management purposes warrants attention because of the possibility of gene flow between cultivated and feral populations. The escape of HR A. stolonifera could lead to risks that are difficult to predict such as more destructive management practices, increased propagule pressure, and loss of community diversity. This project aims to use plant community assemblage data to elucidate potential ecological risk by increasing our understanding of Agrostis habitats, co-occurrence, and plant communities. Targeted transects were conducted in seven different habitat types within the Southern New England Coastal Hills and Plains ecoregion. Where possible, the 7 different habitat types were clustered in 20 locations throughout the ecoregion. During site visits, plants were identified and recorded along a 50 meter transect. The data was used to calculate Shannon’s diversity index within and among habitat types. Nonmetric multidimensional scaling ordination was also performed using Brays-Curtis dissimilarity to visualize differences of Agrostis occurence between communities. There were 74 sites that had Agrostis; a total of 8 different Agrostis species were recorded. The data showed that Agrostis are associated with communities that have higher plant diversity. In this ecoregion, Agrostis co-occur with invasive plants (82%) at a higher rate than communities with invasive plants but no Agrostis (73%). Four non-native Agrostis species were found to have high co-occurrence values, suggesting that there is a high potential for gene flow. Thus, if HR A. stolonifera is approved for commercial use and it escapes, then the use of glyphosate in intermediate, management habitats could select for the genetically engineered plant and its progeny. Herbicide selection could impart long lasting effects upon plant community assemblage and trophic cascades. Supported by grants from the USDA Biotechnology Risk Assessment Program and the Storrs Agricultural Experimental Station.

Broader Impacts:

1 - University of Connecticut, Plant Science, Box U-4163, Storrs, Connecticut, 06269, United States
2 -

Keywords:
ecological risk assessment
Agrostis
plant community
ordination
herbicide resistant
bentgrass
co-occurrence.

Presentation Type: Poster:Posters for Sections
Session: P
Location: Hall A/Convention Center
Date: Monday, August 2nd, 2010
Time: 5:30 PM
Number: PEC005
Abstract ID:113