Sixteen streams in middle and eastern Tennessee were surveyed for the sudden oak-death pathogen Phytophthora ramorum 2010-2012. Surveys were conducted in the spring and fall using healthy Rhododendron leaves, and a total of 354 oomycete isolates were recovered. Sequence analysis of the ITS region provisionally identified 151 Phytophthora, 200 Pythium, two Halophytophthora and one Phytopythium. ...

A new species of Pythium collected from grapevine roots (Vitis vinifera) in South Africa and roots of common beet (Beta vulgaris) in Majorca, Spain, is described. The phylogenetic position of the new species was investigated by multigene sequence analyses of the internal transcribed spacers (ITS1 and ITS2) of the rDNA region, as well as three other nuclear and three mitochondrial coding genes. ...

A new species of Pythium isolated from wheat and apple roots in eastern Washington is described. Pythium abappressorium sp. nov. is characterized by abundant appressoria. Plerotic oospores and sporangia are formed from the appressoria and remnants of the appressoria remain attached to the base of sporangia at maturity. Smaller appressorial swellings, reminiscent of hyphal swellings, are also fo...

Pythium species were isolated from diseased samples of creeping bentgrass and annual bluegrass. Among fourteen isolates from decayed roots and crowns, seven were P. graminicola, five were P. torulosum and two were P. ultimum. These species were identified by comparison of cultural and morphological characteristics to literature and reference isolates. In a tissue culture plate assay for quantif...

Plants can influence the soil they grow in, and via these changes in the soil they can positively or negatively influence other plants that grow later in this soil, a phenomenon called plant-soil feedback. A fascinating possibility is then to apply positive plant-soil feedback effects in sustainable agriculture to promote plant growth and resistance to pathogens. We grew the cut flower chrysant...

The plant growth-promoting rhizobacterium Pseudomonas aeruginosa 7NSK2 produces three siderophores when iron is limited: the yellow-green fluorescent pyoverdin, the salicylate derivative pyochelin, and salicylic acid. This Pseudomonas strain was shown to be an efficient antagonist of Pythium-induced damping-off. The role of pyoverdin and pyochelin in the suppression of Pythium splendens was inv...

Stenotrophomonas maltophilia W81 can protect sugar beet against PYTHIUM:-mediated damping-off disease through the production of an extracellular protease. Here, the proteolytic enzyme of W81 was purified by anion-exchange chromatography and characterized as a serine protease. The purified enzyme was fungicidal against PYTHIUM: ultimum in vitro. Its synthesis was inducible by casein in W81, and ...

BACKGROUND Pythium insidiosum keratitis is a rare but sight-threatening disease with a high morbidity rate. It can be misdiagnosed as fungal keratitis in clinic settings. We report a case of severe Pythium insidiosum keratitis in a Chinese child, treated with combined approaches. CASE REPORT A 7-year-old boy from Hainan province in the south of China developed a suppurative corneal ulcer after ...

The genus Phytopythium (Peronosporales) has been described, but a complete circumscription has not yet been presented. In the present paper we provide molecular-based evidence that members of Pythium clade K as described by Lévesque & de Cock (2004) belong to Phytopythium. Maximum likelihood and Bayesian phylogenetic analysis of the nuclear ribosomal DNA (LSU and SSU) and mitochondrial DNA cyto...

DNA from 14 Pythium species, Verrucalvus flavofaciens and Zoophagus insidians was characterized by CsCl-bisbenzimide density gradients in order to investigate its taxonomic potential. A few incomplete analyses were made for other species. All clearly assignable Pythium species produced three DNA bands in the gradient. Pythium undulatum along with Verrucalvus and Zoophagus produced only two band...