Pythium insidiosum is an aquatic oomycete microorganism that causes the fatal infectious disease, pythiosis, in humans and animals. The organism has been successfully isolated from the environment worldwide. Diagnosis and treatment of pythiosis is difficult and challenging. Genome sequences of P. insidiosum, isolated from humans, are available and accessible in public databases. To further faci...

Sequence analysis of the ribosomal DNA internal transcribed spacers (ITS) was used to establish phylogenetic relationships among 23 isolates of Pythium insidiosum, the etiological agent of pythiosis in mammals. The isolates were divided into three distinct clades that exhibited significant geographic isolation. Clade I consisted of isolates from North, Central, and South America, while clade II...

OBJECTIVES The purpose of this study was to compare the in vitro susceptibilities of 22 Brazilian isolates of Pythium insidiosum to antifungals using a standardized inoculum of zoospores and a proposed novel inoculum prepared from cultured mycelia (hyphae) of P. insidiosum. METHODS A zoospore suspension of P. insidiosum was obtained by the zoosporogenesis technique. The hyphal inoculum was pr...

Predators may have multiple effects on prey, including the mortality caused by consumption, but also non-consumptive effects when prey alter their life history traits in the presence of predators. This study aimed to describe the consumption ability and the non-consumptive effects of Notonecta sellata (Heteroptera: Notonectidae) on immature stages of Culex pipiens (Diptera: Culicidae). Results ...

Ray-Kuang Lee, Yinchieh Lai, and Yuri S. Kivshar Nonlinear Physics Centre and ARC Centre of Excellence for Quantum-Atom Optics, Research School of Physical Sciences and Engineering, The Australian National University, Canberra, ACT 0200, Australia Department of Photonics and Institute of Electro-Optical Engineering, National Chiao-Tung University, Hsinchu 300, Taiwan sReceived 27 December 2004;...

Damping-off of chilli caused by Pythium aphanidermatum is a major nursery disease in vegetables. In vitro experiments evaluated the effect of eight isolates of Trichoderma species (from chilli rhizosphere) were tested against P. aphanidermatum. All the Trichoderma species had varied antagonistic effects against the pathogen. Among them, TVC3 recorded maximum growth inhibition of P. aphanidermat...

Fungal and oomycete populations and their dynamics were investigated following the introduction of the biocontrol agent Pythium oligandrum into the rhizosphere of tomato plants grown in soilless culture. Three strains of P. oligandrum were selected on the basis of their ability to form oospores (resting structures) and to produce tryptamine (an auxin-like compound) and oligandrin (a glycoprotei...

Pythium aphanidermatum is one of the common causal pathogen of damping-off disease of beans (Phaseolus vulgaris L.) grown in Manipur. A total of 110 indigenous Trichoderma isolates obtained from North east India were screened for their biocontrol activity which can inhibit the mycelial growth of P. aphanidermatum, the causal organism of damping-off in beans. Out of the total isolates, 32% of th...

Twenty-eight isolates of Pythium insidiosum and P. destruens from Asia, Australia and the Americas were compared on the basis of restriction fragment-length polymorphisms of the amplified ribosomal intergenic spacer. Comparison of band profiles yielded three distinct clusters and an isolate that did not fall into any of the clusters. Cluster I consisted of 16 isolates, all from the Americas (Co...

Damping-off diseases incited by different species of Pythium are a persistent problem worldwide, often resulting in reduced yields and occasionally resulting in major crop damage. There have been increasing restrictions on the use of chemical fungicides, and the development of disease-suppressive biocontrol agents has become a major goal of horticulture crops. An experiment was conducted with t...