Abstract Detail

Mycological Section

Ledall, Brittany  [1], Beckstead, Julie [2], Van Volkom, Kaitlin  [1].

Restoration Opportunity: Understanding the effects of naturally occurring pathogens on native and nonnative grasses under water stress conditions.

Despite the broad success of the invasive species Bromus tectorum (cheatgrass), in the American West, the phenomenon known as die-off has been observed in the field and has affected large areas of cheatgrass. Die-off is described as stand failure, which results when seedlings fail to emerge or are killed post emergence, prior to seed production. Primary suspects for these die-offs are naturally occurring fungal pathogens such as Fusarium sp. and Cochliobolus pallescens. This phenomenon may present a unique opportunity for restoration with native grasses, but the pathogens’ effects on native grasses is unknown. Our primary goal was to expose cheatgrass seeds and the native grass seeds, Elymus elymoides (squirretail), to the two pathogens to study the effects on seedling emergence, height and biomass. The results show that native grasses inoculated with the pathogens had higher biomass and height in comparison to cheatgrass inoculated with the pathogens.  However, emergence of both species was not impacted by the pathogens.  In addition, water stress is an important element for the effectiveness of pathogens, due to drought conditions in the field. In a second experiment, water stress was introduced to the seeds, along with the two pathogens. This experiment showed that 34% cheatgrass seeds did not emerge when exposed to water stress in comparison 3% non-emergence without water stress. This data raises questions of pathogen and seedling dynamics, under water stress. The results of these experiments expand our knowledge of die-off-causing pathogens and their effects on invasive and native grasses for restoration opportunities.

1 - Gonzaga University , Biology Department , 502 E. Boone Ave , Spokane , WA, 99258, USA
2 - Gonzaga University, Department Of Biology, 502 E. Boone Avenue, Spokane, WA, 99258, USA

Keywords:
Restoration Ecology
Bromus tectorum
cheatgrass
die-offs
plant pathogen interactions
seedling establishment.

Presentation Type: Poster:Posters for Sections
Session: P
Location: Eyrie/Boise Centre
Date: Monday, July 28th, 2014
Time: 5:30 PM
Number: PMY003
Abstract ID:279
Candidate for Awards:None