| disease progression by active mycelial growth and biocontrol of pythium ultimum var. ultimum studied using a rhizobox system. | abstract this study demonstrates that outward growth of mycelium from primary foci through bulk potting mix to roots of adjoining plants can be an important means of spread of damping-off and root rot caused by pythium ultimum. the use of a rhizobox system, which confines plant roots, enabled us to study the spread of actively growing mycelium between root systems placed at precise distances from each other. in steamed potting mix, hyphae of p. ultimum on average grew 9.6 cm from diseased root t ... | 2000 | 18944533 |
| phytophthora cinnamomi and other fine root pathogens in north temperate pine forests. | 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 forest. morphological and molecular data supported the identification of phytophthora cinnamomi from three ... | 2007 | 17937665 |
| [development of pythium ultimum var. ultimum trow on different cultural media depending on temperature]. | pythium ultimum var. ultimum 175 was isolated for the first time from root system of rape. influences of two kinds of temperature (10 and 25 degrees c) and 8 different cultural media on the strain growth and development was investigated. using the growth-rate criterion the author has determined linear velocity of growth, which varied from 0.43 to 0.68 mm/h at 10 degrees c and from 0.78 to 1.11 mm/h at 25 degrees c. as to the velocity of growth the culture p. ultimum var. ultimum 175 is comparabl ... | 2005 | 16396111 |
| isolation of pythium oligandrum from egyptian soil and its mycoparasitic effect on pythium ultimum var. ultimum the damping-off organism of wheat. | pythium oligandrum drechsler bearing spherical sporangia with complex subglobose elements was isolated for the first time in egypt from agricultural field soil cultivated with alfalfa (trifolium alexandrinum) in el-minia, egypt. this fungus was found to be an active bio-control agent against p. ultimum var. ultimum, the damping-off organism of wheat. in agar plates, p. oligandrum parasitized p. ultimum var. ultimum hyphae with the aid of thin haustorial branches or infection pegs, eventually lea ... | 1997 | 16284719 |
| chilling resistances of isolates of pythium ultimum var. ultimum from the arctic and temperate zones. | chilling resistances in moss pathogenic fungi, pythium ultimum var. ultimum, from longyearbyen, svalbard (78 degree n, 15 degree e), located in the arctic zone and in the same isolates from temperate zone, were determined. both strains had similar optimum growth temperatures. however, the strains from svalbard could grow and survive at 0 - 5 degrees c. in addition, chilling treatment induced irregular mycelial morphology in the arctic isolates. on the other hand, the isolates from japan did not ... | 2002 | 12148017 |
| genetic variation in homothallic and hyphal swelling isolates of pythium ultimum var. ultimum and p. utlimum var. sporangiferum. | genetic variation in a collection of 22 pythium ultimum isolates was analyzed using restriction fragment length polymorphisms (rflps), random amplified polymorphic dna (rapd), and sequence characterized amplified regions (scars) as genetic markers. qualitative evidence for the occurrence of sexual outcrossing in the field, asexual mechanisms affecting variation, and differences in aggressiveness between isolates was found. codominant scar and rflp markers detected multiple alleles in several iso ... | 1994 | 7873781 |
| mutagenesis of beta-1,3-glucanase genes in lysobacter enzymogenes strain c3 results in reduced biological control activity toward bipolaris leaf spot of tall fescue and pythium damping-off of sugar beet. | abstract lysobacter enzymogenes produces extracellular lytic enzymes capable of degrading the cell walls of fungi and oomycetes. many of these enzymes, including beta-1,3-glucanases, are thought to contribute to the biological control activity expressed by several strains of the species. l. enzymogenes strain c3 produces multiple extracellular beta-1,3-glucanases encoded by the glua, glub, and gluc genes. analysis of the genes indicates they are homologous to previously characterized genes in th ... | 2005 | 18943787 |