| genetic exchange and recombination in populations of the root-infecting fungus armillaria gallica. | genetic individuals, or genets, of armillaria and other root-infecting basidiomycetes are usually found in discrete patches that often include the root systems of several adjacent trees. each diploid individual is thought to arise in an unique mating event and then grow vegetatively in an expanding territory over a long period of time. our objective in this study was to describe the population from which such genetic individuals are drawn. in a sample including 274 collections representing 121 g ... | 1996 | 8794559 |
| mtdna recombination in a natural population. | variation in mtdna has been used extensively to draw inferences in phylogenetics and population biology. in the majority of eukaryotes investigated, transmission of mtdna is uniparental and clonal, with genotypic diversity arising from mutation alone. in other eukaryotes, the transmission of mtdna is biparental or primarily uniparental with the possibility of "leakage" from the minority parent. in these cases, heteroplasmy carries the potential for recombination between mtdnas of different desce ... | 1998 | 9448331 |
| a genetic mosaic in the fruiting stage of armillaria gallica. | the basidiome stage of armillaria gallica can be a genetic mosaic. ten cells isolated from a single basidiome in 1986 produced nine different genotypes when analyzed for variation at six nuclear loci. four additional basidiomes collected in 1986 produced mosaic patterns when analyzed for variation at a single nuclear (pcr-rflp) locus. one basidiome collected in 1993 was not a genetic mosaic because 15 cells isolated from it produced only one genotype when analyzed for six nuclear loci. two hundr ... | 2000 | 10919376 |
| phenotypic plasticity and evolutionary potential in somatic cells of armillaria gallica. | somatic cells of armillaria gallica fruit bodies have been shown to possess different genotypes for molecular-marker and mating-type loci. here we report experiments on six quantitative traits and demonstrate that somatic cells of fruit bodies possess almost as much genetic variation for growth rate and phenotypic plasticity as do spores, the products of meiosis. genetically distinct somatic cells therefore have the potential to grow at different rates relative to one another during primordial f ... | 2003 | 12825512 |
| nonspecific elicitation of defense reaction in suspension tobacco cells by elicitors from armillaria. | ergosterol and chitin oligomers were detected in water extracts from armillaria gallica, a. cepistipes, a. tabescens, a. ostoyae and a. mellea containing as active components elicitors able to trigger early events of defense reaction in suspension tobacco cells. more virulent strains of a. ostoyae and a. mellea had the same ability of elicitation as weak pathogens a. gallica, a. cepistipes, a. tabescens. the elicitation of the defense reaction early events by chitin oligomers was markedly enhanc ... | 2005 | 16110917 |
| haploid vegetative mycelia of armillaria gallica show among-cell-line variation for growth and phenotypic plasticity. | vegetative mycelial cells of armillaria are expected to have diploid nuclei. cells from a single mycelium therefore would not be expected to differ from one another for ecologically relevant quantitative traits. we isolated two sets of basidiome cell lines (from spores and stipe cells) and one set of vegetative cell lines (from an attached rhizomorph) from a single contiguous armillaria gallica mycelium. we isolated a second set of vegetative cell lines from the soil 20 cm from the above basidio ... | 2005 | 16457347 |
| network formation by rhizomorphs of armillaria lutea in natural soil: their description and ecological significance. | armillaria lutea rhizomorphs in soil were mapped over areas of 25 m2 at a pinus nigra (site i) and a picea abies (site ii) plantation. rhizomorph density was 4.3 and 6.1 m m(-2) soil surface with 84% and 48% of the total rhizomorph length in the mapped area interconnected in a network at site i and site ii, respectively. at site i there were only two network attachments to pinus stumps, but at site ii many more to picea roots and stumps. anastomoses of rhizomorphs resulted in cyclic paths, parts ... | 2007 | 17645531 |
| dynamics of bioluminescence by armillaria gallica, a. mellea and a. tabescens. | although fungal bioluminescence is well documented, the ecological significance is poorly understood. we examined bioluminescence by three sympatric species of armillaria wood decay fungi, differing in parasitic ability. luminescence by mycelia of four genets of a. gallica, a. mellea and a. tabescens was examined in response to environmental illumination or mechanical disturbance. luminescence dynamics were assessed in a time series of measurements every 2 min for 72 h for mycelia growing on mal ... | 2007 | 17883025 |
| biomechanics of invasive growth by armillaria rhizomorphs. | rhizomorphs of wood-decay basidiomycetes are root-like structures produced by the coordinated growth of thousands of hyphae. very little is known about their development nor the way that they penetrate soils and rotting wood. in this study, we applied techniques used in previous studies on hyphae to explore the mechanics of the invasive growth process in armillaria gallica. growth rate measurements were made in media with different gel strengths. the osmolyte composition of rhizomorph sap was de ... | 2009 | 19427390 |
| cloning and characterization of an armillaria gallica cdna encoding protoilludene synthase, which catalyzes the first committed step in the synthesis of antimicrobial melleolides. | melleolides and related fungal sesquiterpenoid aryl esters are antimicrobial and cytotoxic natural products derived from cultures of the homobasidiomycetes genus armillaria. the initial step in the biosynthesis of all melleolides involves cyclization of the universal sesquiterpene precursor farnesyl diphosphate to produce protoilludene, a reaction catalyzed by protoilludene synthase. we achieved the partial purification of protoilludene synthase from a mycelial culture of armillaria gallica and ... | 2010 | 21148562 |
| evaluation of partial tef1, rpb2, and nlsu sequences for identification of isolates representing armillaria calvescens and armillaria gallica from northeastern north america. | armillaria calvescens and armillaria gallica are two of the most closely-related species of armillaria in north america and have been difficult to distinguish from one another using morphological and molecular techniques. in an attempt to better distinguish these two species, partial sequences of the elongation factor-1 alpha (tef1), rna polymerase ii (rpb2), and nuclear large subunit (nlsu) genes were generated for 32 total isolates; 12 isolates each for a. calvescens and a. gallica, along with ... | 2011 | 21802054 |
| genotypic diversity of armillaria gallica from mixed oak forests in massachusetts. | the population structure of armillaria gallica, an important pathogen of quercus spp., was investigated from mixed oak forests in central massachusetts, encompassing a sampling area over 500 km(2). from 16 plots at four sites, a total of 153 isolates (34 to 40 isolates per site) were analyzed using amplified fragment length polymorphisms (aflps). analyses of 204 polymorphic loci detected 38 aflp genotypes from a sample area of 4.51 hectares (ha). genets ranged in distribution from five to 33 gen ... | 2011 | 21914822 |