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. Members of this genus are defined by the formation of ectoplasmic networks in which the unicellular somatic cells move or 'glide'. Infections of cool-season turfgrasses occur most commonly when they are irrigated with suboptimal irrigation water with elevated salinity. Disease has been observed in 11 states in the United States and in the United Kingdom. A phylogenetic study indicates that isolates from turfgrass in the United States fall firmly within a clade containing other Labyrinthula spp. and that they came from a common lineage. Its rapid emergence as a turfgrass pathogen may coincide with increased use of relatively high-salinity water or reclaimed water for irrigation. L. terrestris is a potential problem in susceptible turfgrass varieties wherever soil salinity is allowed to accumulate as a result of poor soil structure or suboptimal quality irrigation water is used for irrigation.

A quantitative real‐time polymerase chain reaction assay for the seagrass pathogen Labyrinthula zosterae

“…form extracellular networks for communication, nutrient transport and locomotion (Preston & King 2005). They are commonly associated with seagrasses and macroalgae, and more recently with terrestrial plants (Olsen 2007; Douhan et al. 2009).…”

The US National Mall Microbiome: A Census of Rhizosphere Bacteria Inhabiting Landscape Turf

“…Reclaimed water use in turf irrigation systems may lead to the influx of human pathogenic microorganisms, such as the presence of fecal bacteria documented from golf courses in Hawaii (Murakami and Ray, 2008). The rapid emergence of the novel phytopathogen Labyrinthula terrestris , the causal agent of turf rapid blight disease, is thought to have occurred due to increased use of reclaimed water in golf course irrigation systems (Olsen, 2007). Living plant material used for turf renovation and establishment, including commercial sources of grass seed and sod, provides an abundant source of latent microbial pathogens, nematodes, endophytes, and other microscopic organisms (Schardl et al, 2004; Crouch et al, 2009; Entwistle et.…”

Not in your usual Top 10: protists that infect plants and algae

“…Rapid blight disease (RBD) in turfgrasses is caused by the terrestrial species L. terrestris in high-salinity environments, such as salt lakes and golf course turf (Douhan et al, 2009;Kerrigan et al, 2012). This pathogen may have become important in specialized turfgrass because of increased salinity in irrigation or the use of reclaimed water, causing increased turf salinification (Olsen, 2007;Stowell et al, 2005). Both L. zosterae and L. terrestris vary greatly in virulence to their hosts (Chitrampalam et al, 2015;Douhan et al, 2009;Martin et al, 2016).…”

“…). These pathogens are therefore found on the edges of progressing infections rather than within the host lesions (Muehlstein, ; Olsen, ; Sullivan et al ., ). They can be isolated from infected leaf tissues as they emerge from tissues plated onto serum seawater agar solutions (Fig.…”