Haploid monokaryotic basidiocarp tissues in species of Armillaria

Abstract

Viable spores and ethanol-fixed basidiocarps of Armillaria species were collected at eight geographic localities within the northeastern United States. Crosses among haploid hyphae grown from isolated single spores revealed that three to five intersterility groups were represented in this sample. By using spores to establish expected quantities of DNA within haploid cells, fluorescence microspectrophotometric measurements of stipe hyphae fell within the haploid range in all eight geographic isolates. Haploid monokaryotic basidiocarp tissues are unexpected in Basidiomycetes and may indicate the existence of a new pattern for the distribution of genetic material among somatic cells.

A Genetic Mosaic in the Fruiting Stage of Armillaria gallica

“…However, we reported that A. gallica basidiomes collected in Bridgewater, Massachusetts, were monokaryotic and haploid, because no quantitative differences were found when the nuclear DNA content of haploid spores and three different basidiome cell types were compared (Peabody and Peabody, 1985). To determine whether this geographic isolate of A. gallica was atypical, eight additional isolates were sampled and basidiomes were all found to be monokaryotic and haploid (Peabody and Peabody, 1987).…”

Mosaic fungal individuals have the potential to evolve within a single generation

“…For comparison, cultured lines were compared to samples fixed in 95% ethanol within 2 h of collection from nature. These samples included 30 prophase I basidia nuclei, 30 spore nuclei, and 50 rhizomorph and soil mycelia (vegetative-stage) nuclei 8 , 17 , 18 (Supplementary Table S1 ). Because vegetative-stage nuclei and cultured rhizomorph nuclei were not normally distributed (Fig.…”

“…But since other studies show vegetative stages can possess recombinant, haploid nuclei, an alternative hypothesis has been advanced. This hypothesis proposes a life cycle in which a vegetative-stage haploidization produces HGM 6 , 7 , 17 , 18 . Our analyses confirm that vegetative-stage hyphae can be haploid (Fig.…”

“…The use of spores as haploid standards was supported by Baumgartner's independent analyses of banding patterns in 4 polymorphic microsatellite loci and 2 polymorphic nuclear loci of Raynham spore samples (personal communication www.nature.com/scientificreports/ Examination of mycelia for evidence of cytoplasmic bridges. Cultured spore cell lines, stipe hyphal filament lines, rhizomorph hyphal filament lines, and spore, stipe, and rhizomorph samples fixed in 95% ethanol within 2 h of collection from nature were stained with DAPI 17,18 . Samples were initially scanned for the presence of cytoplasmic bridges connecting adjacent hyphae using phase contrast microscopy and then examined for the presence of DAPI-stained nuclei near or in cytoplasmic bridges using epifluorescence.…”

Armillaria in the Northern Rockies : delineation of isolates into clones /

“…Existence of these haploids may not be so surprising in light of the recent reports of haploid tissues in Armillaria spp. basidio-carps (Peabody and Peabody 1986). Our tentative conclusion based on the challenge behavior of some isolates is that our random samples of vegetative structures most probably included some haploids.…”