Influence of salinity, temperature, and nutrient availability on the respiration of saprolegniaceous fungi (Oomycetes)

Abstract

Three isolates representing two species of the Saprolegniaceae were investigated using standard manometric techniques to determine what effect culture temperature and nutrient availability had on respiration following treatment with artificial seawater. All three isolates manifested decreased respiration following treatment in most temperatures and salinities whether or not exogenous nutrient were present, but no treatment prevented test fungi from resuming vigorous growth and infesting sterile bait after the 18.5 h treatment period. In light of previous published reports the present result suggest that saprolegniaceous fungi may become dormant in estuarine salinity regimes, but probably remain viable for prolonged periods. Ecological implications of this phenomenon are discussed.

Structurally preserved fungi from Antarctica: diversity and interactions in late Palaeozoic and Mesozoic polar forest ecosystems

“…One group of fungus-like organisms that appears to have been quite abundant in several peat-forming palaeoenvironments of Antarctica is the Peronosporomycetes (Oomycota). In modern ecosystems, Peronosporomycetes function as saprotrophs and facultative or obligate parasites of plants, animals and other fungi (Padgett et al 1988, Dick 1992, 2001). The fossil record of Peronosporomycetes from Antarctica consists entirely of dispersed microfossils assigned to the fossil genus Combresomyces (Schwendemann et al 2009, Slater et al 2013, Harper et al .…”

Evidence for enhanced salinity tolerance of a suspected fungal pathogen of Atlantic menhaden, Brevoortia tyrannus Latrobe

“…Procedures for this experiment were similar to those described by Padgett et al (1988) except as modified below. Log-phase mycelia of test fungi were prepared for respirometry by incubating zoospores in 50 ml of YpSs/3 broth in 22°C shake flasks.…”

“…The possibility that water moulds might be more salt tolerant than previously suspected is implicit in recent reports by Padgett (1978aPadgett ( ,b,1980Padgett ( ,1984 and Padgett, Kendrick, Hearth & Webster (1988). Such reports raise the possibility that selected water mould isolates might be salt tolerant ecotypes.…”