title: Improved methods for axenic culture of Labyrinthula terrestris, causal agent of rapid blight of turfgrasses.
abstract: The genus  Labyrinthula  is a group of unicellular microorganisms with spindle-shaped cells that move in an ectoplasmic network. Most Labyrinthula species are saprotrophic and found in coastal marine or estuarine habitats; however, exceptions exist, such as  Labyrinthula terrestris , a terrestrial plant pathogen that causes rapid blight on cool-season turfgrasses. Labyrinthula spp. can be grown in culture, which facilitates studies on their biology and pathology. However, axenic culture of L. terrestris has always been challenging. We modified the most commonly used Labyrinthula growth medium, serum seawater agar (SSA), and designed 2 media for improved pure culture, modified SSA (MSSA) and grass extract SSA (GESSA). A comparative assessment of these 2 media and basic SSA was made to measure the growth responses of 18 L. terrestris isolates. Results indicate that the average colony area was greatest on GESSA followed by MSSA, while cultures lived longest on MSSA followed by GESSA. We also suggest an improved long-term culture technique to maintain viable L. terrestris isolates for at least 2 years.
authors.affiliation: School of Agricultural, Forest, and Environmental Sciences, 114 Long Hall, 230 Parkway Drive, Box 340310, Clemson University, Clemson, SC 29634-0310, USA.
authors.forename: Kirthi Kiran
authors.initials: KK
authors.lastname: Yadagiri
authors.forename: Julia
authors.initials: J
authors.lastname: Kerrigan
authors.forename: S Bruce
authors.initials: SB
authors.lastname: Martin
mesh_terms: D000362:Agar; D061245:Axenic Culture / Q000379:methods*; D003470:Culture Media / Q000737:chemistry; D006109:Poaceae / Q000382:microbiology; D058009:Stramenopiles / Q000254:growth & development*
chemical_list: D003470:Culture Media; D000362:Agar