Genetic diversity of Labyrinthula terrestris, a newly emergent plant pathogen, and the discovery of new Labyrinthulid organisms.

Labyrinthuloid organisms are thought almost exclusively to be only associated with marine environments. However in 1995, a disease of turfgrass suddenly appeared that was eventually determined to be caused by a new Labyrinthula species (Labyrinthula terrestris). The disease is primarily thought to be caused by the use of elevated salinity irrigation water, making it a unique example of an emergent plant disease potentially induced by human activity.

Genetic analysis of a novel Xylella fastidiosa subspecies found in the southwestern United States.

Xylella fastidiosa, the causal agent of several scorch diseases, is associated with leaf scorch symptoms in Chitalpa tashkentensis, a common ornamental landscape plant used throughout the southwestern United States. For a number of years, many chitalpa trees in southern New Mexico and Arizona exhibited leaf scorch symptoms, and the results from a regional survey show that chitalpa trees from New Mexico, Arizona, and California are frequently infected with X. fastidiosa.

Labyrinthula terrestris: a new pathogen of cool-season turfgrasses.

ABSTRACT A new disease of turfgrass known as rapid blight is caused by Labyrinthula terrestris, a newly described member of the Labyrinthulids. This unusual group of microorganisms previously has been found in marine systems, and L. terrestris is the only member of the genus Labyrinthula known to be a pathogen of terrestrial plants.