Abstract Detail

Incorporating microbes into plant community ecology

Wilson, Gail W. T. [1], Hickman, Karen R. [1], Williamson, Melinda M, [1].

Invasive species alter arbuscular mycorrhizal densities: implications for restoration.

Soil organisms play important roles in regulating ecosystem-level processes and the association of arbuscular mycorrhizal (AM) fungi with a plant species can be a central force shaping plant species' ecology. These plant-fungal associations have been reported to both constrain and facilitate the ability of an invasive species to successfully expand its range. Understanding how mycorrhizal associations are affected by plant invasions may be a critical aspect of the conservation and restoration of native ecosystems. We assessed AM intra- and extra-radical hyphal densities of two expanding plant species of the Central Great Plains, Bothriochloa spp. (Old World Bluestems) and Juniperus virginiana (Eastern redcedar). Restoration following eradication of these species was also examined. Old World Bluestems are a group of warm-season perennial grasses of Eurasian origin that are a great threat to native prairies of the southern and central Great Plains. These species are functionally similar to native warm-season grasses of these grasslands, and both Bothriochloa and native warm-season grasses are obligate mycotrophs. Eastern redcedar are native to the tallgrass prairie, but are rapidly encroaching into native grasslands in response to global land use change. Examination of soil microbial communities beneath both Old World Bluestem and Eastern redcedar indicated AM inter- and intra-radical colonization increased substantially, compared to adjacent native prairie. We examined plant-soil feedbacks of Old World Bluestem by assessing biomass production and AM colonization of native warm-season grasses planted into soil collected beneath Old World Bluestem. Our results indicated the major driver in plant growth suppression following invasion by Old World Bluestem was the alteration in soil microbial communities. Plant growth was tightly correlated with AM root colonization demonstrating mycorrhizae play an important role in the invasion of these systems by Old World Bluestem and indicating the native AM fungal community may be a fundamental consideration for the successful restoration of native plant communities into invaded sites.

Broader Impacts:

1 - Oklahoma State University, Natural Resource Ecology & Mngt, Stillwater, Ok, 74078, USA

Keywords:
invasive plant
tallgrass prairie
Old World Bluestems
Eastern Redcedar
Arbuscular mycorrhiza.

Presentation Type: Symposium or Colloquium Presentation
Session: SY01
Location: Westminster Room/Chase Park Plaza
Date: Monday, July 11th, 2011
Time: 11:15 AM
Number: SY01007
Abstract ID:577