CRB: The Effects of Barley Yellow Dwarf Virus on Introduced and Native Grass Species in California and Implications for Restoration

Michigan State University, East Lansing MI

Investigators

Abstract

Malmstrom Abstract CRB: The effects of barley yellow dwarf virus on introduced and native grass species in California and implications for restoration Over the last two centuries, introduced plant species have become notable components of many American grasslands, sometimes altering grassland properties and reducing forage quality. The California grasslands are one system in which species composition has been profoundly transformed, in this case from a system dominated by native perennial grasses to one dominated by exotic annuals and now threatened by noxious weeds such as the yellow star thistle. Current efforts to improve the quality of California grasslands include a focus on restoring populations of native perennial grasses. However, restoring native grass populations has not always been straightforward. Evidence suggests that a common cereal virus, barley yellow dwarf virus (BYDV), is a widespread ecological agent in these grasslands and may play a notable role in influencing the population dynamics of the native and annual species. This work investigates interactions between native and introduced grasses and BYDV, and examines the hypothesis that BYDV places a stronger limitation on the persistence of native perennial populations than on those of the introduced annuals. The work will provide valuable insight into the role of plant viruses in natural communities, an area in which current understanding is poor. The information gained about BYDV in particular will be relevant to the many grasslands around the world in which BYDV is common. For California, this work will be the first investigation of a widespread ecological agent that has hitherto been overlooked in analysis of grassland and rangeland dynamics. For grassland and range managers, this work will help assess the trajectories of native grass populations under BYDV pressure and will help evaluate the feasibilit