Tomato agar and soybean agar were found to be comparable to or in some cases better than the popular V8 vegetable juice agar in supporting linear growth of Phytophthora cactorum, Phytophthora capsici, Phytophthora parasitica, Pythium aphanidermatum, and Pythium splendens; sporangium production of P. capsici, P. palmivora, and Pythium splendens; and oospore formation of P. cactorum, P. parasitic...

A number of fine root pathogens, including Phytophthora cinnamomi, Pythium ultimum var. ultimum, Pythium undulatum, Pythium violae, Fusarium sp., and two incompletely identified Verticillium species, were isolated from soils taken from under Scots pine trees at five sites in north Scotland, including semi-natural forests and plantations. At least two root pathogens were recovered from each fore...

Insect larvae that live in temporary ponds must cope with a rapidly diminishing resource. We tested the hypothesis that floodwater mosquitoes would react to diminishing water levels by accelerating larval development time and emerging as smaller adults. Since a reduction in habitat size leads to increased larval densities, we also included two larval densities. Newly-hatched floodwater mosquito...

Attraction, engorgement, mortality, and fecundity were observed on host-seeking Aedes vexans and Psorophora confinnis given the opportunity to feed on insecticide-treated steers in stable traps. Individual steers were treated with Ectrin ear tags, Ectrin spray, Terminator ear tags, Saber ear tags, or Ivomec injection or were left untreated. Aedes vexans and Ps. confinnis accounted for over 98% ...

ABSTRACT Traditional methods of quantifying Pythium spp. rely on the use of selective media and dilution plating. However, high variability is inherent in this type of enumeration and counts may not be representative of the pathogenic population of Pythium spp. Variable regions of the internal transcribed spacer of the rDNA were used to design species-specific primers for detection and quantifi...

Canopy disturbances such as windthrow events have obvious impacts on forest structure and composition aboveground, but changes in soil microbial communities and the consequences of these changes are less understood.We characterized the densities of a soil-borne pathogenic oomycete (Pythium) and a common saprotrophic zygomycete (Mortierella) in nine pairs of forest gaps created by windthrows and...

A new disease causing wilt and death of adult plants of Phaseolus vulgaris was discovered in plastic-house crops of southeast Spain in 2004. The causal agent was shown to be a Pythium species with a unique type of oogonium ornamentation different from any of the described species. Zoospores were not observed, but globose or subglobose hyphal swellings, intercalary or terminal, were frequently f...

The genus Pythium was erected by Pringsheim in 1858 and placed in the family Saprolegniaceae. By the end of 19th century taxonomic details of the genus had been clarified and many new species had been described. The relationship with other Oomycetes was established and the genus was included in a new family, Pythiaceae, by Schroter in 1897. The fungus Pythium belongs to the subdivision Mastigom...

*Globally, exotic invaders threaten biodiversity and ecosystem function. Studies often report that invading plants are less affected by enemies in their invaded vs home ranges, but few studies have investigated the underlying mechanisms. *Here, we investigated the variation in prevalence, species composition and virulence of soil-borne Pythium pathogens associated with the tree Prunus serotina ...