Moist Chamber Cultures Research Articles

The Occurrence of Myxomycete Communities in Taxodium distichum Forests: Influence of Substrates and Seasons

Myxomycete communities in Taxodium distichum forests and the influence of substrates and seasons on myxomycete diversity were studied. In total, 80 substrates (40 living barks and 40 litters) were collected from the sample site in winter, spring, summer and autumn of 2023, followed by moist chamber cultures. A total of 733 records representing 34 myxomycete species in 21 genera were obtained. Arcyria cinerea and six other species were abundant (A). Six species were common (C), six species were occasional (O), and fifteen species were rare (R). Species diversity (H’ = 2.04 ± 0.20) of corticolous communities was significantly higher than that (H’ = 1.49 ± 0.31) of litter-inhabiting communities (p < 0.05). Nonmetric Multidimensional Scaling (NMDS) analyses showed significant differences between these two communities (p < 0.01). Species diversity was slightly higher in summer and autumn compared to winter and spring. NMDS analyses indicated no significant differences among seasonal communities. Redundancy Analysis showed that the corticolous species were closely related to wind speed (p < 0.05), while litter-inhabiting species were mainly determined by temperature (p < 0.05). The study revealed that substrates and seasons influenced myxomycete communities in T. distichum forests, with the communities being particularly affected by the substrates in which they live.

Community structure and assembly of myxomycetes in northern Chinese forests under geographic barriers

ABSTRACT The study of myxomycete biogeography has a long-standing history and has consistently drawn scholarly interest. Nevertheless, studies focusing specifically on the spatial and temporal distribution patterns of myxomycete diversity are relatively limited, with even fewer investigating the mechanisms driving the generation and maintenance of myxomycete diversity. Therefore, this study selected two geographically distant sampling sites within northern Chinese forests to investigate myxomycete species composition, community structure, environmental drivers, and assembly patterns under geographic barriers. We established plots in the Altai Mountains (ALE) and the Greater Khingan Mountains (GKM), gathered bark and litter, and conducted 80-day moist chamber cultures of myxomycetes. Additionally, myxomycete specimens were collected in the field simultaneously to supplement the data set. This study collected 541 myxomycete specimens belonging to 73 species from 28 genera, spanning 12 families and eight orders. The ALE and the GKM had 20 identical species, accounting for 27% of the total species. Myxomycetes from both regions exhibited abundant occurrence 18 days after cultivation, with the quantity on bark substrates notably higher than on litter. Arcyria pomiformis and Comatricha elegans were the most common species in moist chamber cultures. Mantel test outcomes revealed that environmental factors had no significant impact on myxomycete community similarity between the two areas, aligning with findings from the neutral community model analysis, indicating a predominant influence of stochastic processes on myxomycete community structure in moist chamber cultures. This study represents the first application of a quantitative framework to analyze myxomycete community assembly cultivated in moist chambers.

Myxobiota of the İskenderun Gulf (Mediterranean Sea/Türkiye) and its Environment

This study aims to determine the myxobiota of the İskenderun Gulf and its environment. This study was carried out on samples collected from 9 different stations in the İskenderun Gulf district in 2019-2022. Myxomycetes samples were collected from leaves, tree bark, and decayed and non-rotting plant materials. This aim is to detect both the myxobiota of this region and the halophytic myxomycetes species. The collected samples have developed myxomycete sporophores by using the moist chamber technique. In addition, myxomycetes which were developed in their natural environment were collected. As a result of the field and laboratory studies, 161 samples from different localities were collected and processed and 111 myxomycete samples were obtained from these samples. 41 species belonging to 6 ordo, 12 families, and 20 genera have been defined. 3 species were obtained only from the natural environment, 30 species were obtained only from moist chamber culture, and 8 species were obtained from both moist chamber culture and natural area. Arcyria cinerea, Didymium difforme, D. squamulosum, and Physarum pusillum were determined as abundant. While the number of species is rare in the seaside regions, it was observed that the further away from the sea, the number of species increased, especially in forest areas. A. cinerea, D. difforme, and D. dubium are the most common species on the beach and near the seaside. While cosmopolitan species were observed in abundance, Physarida members were found to be common in this results area. This study has contributed to the myxobiota of Türkiye.

Myxomycetes of Subantarctic Macquarie Island

An expedition to subantarctic Macquarie Island was carried out during the period of late January to early May of 1995 with the objective of documenting myxomycete biodiversity. Collecting on the island yielded 412 field collections, with another 14 collections were obtained with the use of the moist chamber culture technique. A total of twenty-six species representing 13 genera was recorded. This is the largest set of data yet available on the myxomycetes associated with any high-latitude area of the Southern Hemisphere. Prior to the expedition, only a single species was known from Macquarie Island. The purpose of this paper is to describe this expedition from the viewpoint of the author.

An inexpensive moist chamber culture technique for finding microbiota on live tree bark.

Traditional moist chamber cultures (MCs) prepared in aseptic laboratory environments using sterile Petri dishes are commonly used to quantify the microbiota of rough-bark tree species and woody vines. MCs are typically expensive and may be difficult to make, so a less expensive option made from easily available supplies was developed. These cost-friendly MCs were compared with standard laboratory methods to demonstrate their efficacy. Modified MCs were made using inexpensive, store-bought supplies; compared to a standard laboratory setting, the modified MCs are shown to be less expensive with a faster setup time and larger size that facilitates a variety of tree and woody vine species. MC use resulted in the discovery of new species of fungi and myxomycetes with associated locality records. We provide detailed instructions for creating modified MCs, as well as a list of myxomycete species and their associated bark characteristics, pH values, and water-holding capacity. This new, low-cost MC technique makes the study of microbiota more inclusive and accessible for those in research laboratories, classrooms, and homes, including both amateurs and professionals. MCs are easy to prepare, versatile, and applicable for many areas of botany and the biological sciences, potentially allowing exploration into unexplored areas in urban ecosystems.

Didymium arenosum, a myxomycete new to science from the confluence of deserts in northwestern China.

A new myxomycete species, Didymium arenosum, was described based on morphological evidence and phylogenetic analyses. The species was discovered in the arid region at the confluence of the Badain Jaran desert and Tengger desert on the leaves of Betula platyphylla and was cultivated in a moist chamber culture. Morphologically, the species is distinguished by the greenish-yellow calcium carbonate crystals on the surface and the spores covered with small warts, some of which are connected into a short line. A phylogenetic analysis of D. arenosum strongly supports its classification as a separate clade. The spore to spore agar culture of D. arenosum requires 23 days, and this study provides a detailed description of its life cycle.

Diversity of Myxomycetes from Peru Part III: The high Andes and the altiplano

The results obtained from a survey for Myxomycetes in the Peruvian Andes (between 3,000 and 5,000 m a.s.l.) are reported. This survey is based on 3,352 identifiable collections of myxomycetes, resulting from sampling carried out during six field expeditions of the Myxotropic Project, from moist chamber culture and the revision of deposited specimens in the HSP herbarium. In total, 178 taxa representing 31 genera were recorded. Ten species are considered new records for South America or the Neotropics, and 53 additional new records for Peru are reported. Notes and SEM micrographs of relevant species are included. The best-represented order was Physarales with 55% (99 species), followed by Trichiales (43 species), Stemonitidales (21 species), Cribrariales (14 species), and the least represented was Echinosteliales (1 species). The most diverse genera were Physarum and Didymium, with 43 and 24 spp., respectively. The most abundant species were Didymium nigrisporum, with 336 collections and Didymium difforme, with 156 collections. These data, together with those obtained at other elevations in the country and in the Southern Andes, confirm the high diversity of myxomycetes of Peru, show the biological value of the Andes Cordillera and highlight the vital role that it plays in the distribution of these microorganisms. The study confirms the striking differences between the species assemblages in different vegetation belts of the tropical Andes, with only 18% of the species recovered in all three studied areas in Peru.

Results of myxomycete experiments could be affected by temperature in “standard” laboratory conditions

Moist chamber cultures are valuable for myxomycete research and can be used for the analysis of ecological patterns with implications in ecosystem conservation programs. However, to make comparisons between datasets valid, the method should be redesigned considering potential biases affecting the generation of results. In the present study, both the effect of the general climate of the laboratory and two microclimatic variables within the moist chamber were studied in relation with the obtained data. Of all the recorded variables, temperature was observed to affect the results, both at the level of the general laboratory climate and in relation with the microclimate of the moist chamber. Increments in laboratory and moist chamber temperature increased the probability, three or fourfold, associated with a higher number of records or species within a group of equivalent samples. Such probabilistic differences are significant enough to suggest that using the moist chamber technique in “standard” laboratory conditions is not enough for cross-dataset comparisons that increase the potential of myxomycete data for applications outside of the biological sciences.

Myxomycetes associated with the bark, cones and leaves of Australian cypress pines (Callitris spp.)

Context The diversity of myxomycetes associated with Australia’s most diverse native conifer genus, Callitris, has been incompletely studied.Aims In this study, we examine the diversity of myxomycetes associated with outer bark, fallen cones and dead litter (leaves/needles) of four Callitris species.Methods Substrate samples were collected from 13 localities in New South Wales, Queensland and the Northern Territory. Samples were used to prepare moist-chamber cultures, and species of associated myxomycetes were identified.Key results Twenty-three species in 15 genera were recorded. Percentage occurrence of myxomycetes varied depending on substrate, being 87% (cones), 83% (bark) and 63% (litter). Bark yielded the most species (17), followed by litter (10) and cones (6). Only two species (Arcyria cinerea and S. fusca) were recorded from all three substrates. Substrate pH is often an important factor for the occurrence of myxomycetes, but the mean values recorded for cones (5.7), litter (5.8), and bark (5.9) showed little difference. This suggests that other undetermined factors contributed to the differences in species occurrence. In addition to the records generated in the present study, we provide a list of previous records of myxomycetes found in association with Callitris.Conclusions This study has highlighted, for the first time, the diversity of myxomycetes associated with members of the genus Callitris and has shown the importance of cypress pines as a substrate for myxomycetes.Implications This study leads to a better understanding of the biogeography, distribution and ecology of myxomycetes and their associated organisms.

Myxomycetes associated with Australian vertebrate dung

ABSTRACT Little is known about species of myxomycetes associated with vertebrate dung in Australia. In the present study, dung samples of 15 species of mammals (eight marsupials, three native rodents and four domestic or feral eutherians) and a large flightless bird (the southern cassowary, Casuarius casuarius) were collected and processed in 84 moist chamber cultures. Fifty-two percent of these cultures yielded evidence (fruiting bodies and/or plasmodia) of myxomycetes. Eleven species belonging to seven genera were recorded. Licea tenera was the most common species in the study (recorded from 12 moist chamber cultures) and is also a new record for the continent. Perichaena depressa, Didymium difforme and Cribraria violacea were the only other species appearing in at least three cultures. Samples of dung collected from small mammals did not yield any myxomycetes.

Association between corticolous myxomycetes and tree vitality in Cryptomeria japonica.

The bark of live trees provides an important microhabitat for corticolous myxomycetes. However, the association between the presence of myxomycetes and health of host trees has not been studied in detail. In this study, we aimed to investigate the relationship between tree vitality and myxomycetes on the bark of Cryptomeria japonica trees in a montane forest in western Japan. The vitality of trees was categorized into four grades based on the visual assessment of tree shape and leaf density in the upper branches. Myxomycetes on the bark surface were examined using the moist chamber culture method. A decline in tree vitality increased bark pH and decreased electrical conductivity of the bark exudates. Seventeen myxomycete species were recorded in 74 C. japonica trees. The structure of myxomycete communities varied between healthy and unhealthy trees, and species diversity increased as the vitality declined. The relative abundance of Cribraria confusa decreased as the vitality declined, while that of Paradiacheopsis solitaria increased. The results showed that acidophilic myxomycetes grew on healthy C. japonica bark, but changes in bark pH associated with vitality decline led to the weakening of acidity and shifted the community structure; thus, corticolous myxomycete diversity was enhanced as tree vitality decline.

Новые данные о разнообразии миксомицетов Республики Татарстан (Россия)

A checklist is provided for species of myxomycetes found in the Republic of Tatarstan (Russia), including new records from the Volzhsko-Kamsky Reserve and the outskirts of the city of Kazan. The annotated list includes 85 species found by the authors, of which 77 were recorded in the field (484 specimens) and 17 — from moist chamber cultures (117 specimens). Sixty-seven species were found only in the field, and eight species were obtained only in moist chamber cultures. Sixty-one species of myxomycetes are recorded for the first time in the Republic of Tatarstan. Four rare species — Craterium dictyosporum, Echinostelium paucifilum, Oligonema intermedium, and Stemonaria fuscoides are new for Russia. Twenty-five species known from the literature are also included in the additional list. In total, 110 species of myxomycetes are known from the Republic of Tatarstan.

Observations of the impact of bushfire on a community of myxomycetes

In this study, we examined the impacts of a bushfire on a community of myxomycetes (also known as plasmodial slime moulds or myxogastrids) in northeastern New South Wales, Australia. Using the moist chamber culture technique, we prepared 40 moist chamber cultures from four different substrates. We collected the same four types of substrates on either side of a fire line approximately six months post-fire in order to assess what impact fire had on the myxomycete communities. Sixty percent of moist chamber cultures yielded evidence (plasmodia or fruiting bodies) of myxomycetes representing eleven species in eight genera. But only 40% of samples from the burned site were positive for myxomycetes, and only one species produced fruiting bodies. In contrast, 80% of samples from the unburned site were positive, and all eleven species were recorded. These data suggest that fire reduced the abundance and diversity of the myxomycete community at our site.

First records of Myxomycetes associated with members of the Cactaceae in Australia

Context Cacti are endemic to North and South America, but numerous species have been spread all over the world after Europeans visited the Americas. Their global spread has impacted various aspects of terrestrial ecosystems, including the distributions of succulenticolous myxomycetes. Aims In this study, we examine the association of myxomycetes (also known as plasmodial slime moulds or myxogastrids) with three introduced species of cacti in Australia. Methods Using the moist chamber culturing technique we prepared 33 cultures from dead portions of three species of cacti collected in New South Wales and Queensland. Key results Eighty-eight percent of moist chamber cultures yielded evidence of myxomycetes (either plasmodia or fruiting bodies). A total of 12 species representing six genera were recorded. Physarum compressum was the most abundant species (appearing in 20 of the 33 cultures), with species such as Perichaena depressa also relatively common. We also report the first records of Perichaena luteola in Australia. Conclusions This is the first study to investigate the assemblages of myxomycetes associated with members of the Cactaceae in Australia, and we highlight the occurrence of succulenticolous myxomycetes on the continent. Implications This study leads to a better understanding of the biogeography, distribution and ecology of succulenticolous myxomycetes. We also add a new species record for Australia.

Schroeteria decaisneana, S. poeltii, and Ciboria ploettneriana (Sclerotiniaceae, Helotiales, Ascomycota), three parasites on Veronica seeds: first report of teleomorphs in Schroeteria

Ciboria ploettneriana, Schroeteria decaisneana, and S. poeltii produce morphologically very similar apothecia emerging from fallen stromatized seeds of Veronica spp., the former two on V. hederifolia agg. in temperate central Europe and S. poeltii on V. cymbalaria in mediterranean southern Europe. They are described and illustrated in detail based on fresh collections or moist chamber cultures of infected seeds. A key is provided to differentiate the three species from their teleomorphs. For the first time, connections between two teleomorphs and two Schroeteria anamorphs are reported. Members of the anamorph-typified genus Schroeteria are known as host-specific plant parasites that infect seeds of different Veronica spp. In earlier times, they were classified in the Ustilaginales (Basidiomycota), but since more than 30 years, they are referred to as false smut fungi producing smut-like chlamydospores, based on light microscopic and ultrastructural studies which referred them to the Sclerotiniaceae (Helotiales). During the present study, rDNA sequences were obtained for the first time from chlamydospores of Schroeteria bornmuelleri (on V. rubrifolia), S. decaisneana (on V. hederifolia), S. delastrina (generic type, on V. arvensis), and S. poeltii (on V. cymbalaria) and from apothecia of C. ploettneriana, S. decaisneana, and S. poeltii. As a result, the anamorph-teleomorph connection could be established for S. decaisneana and S. poeltii by a 100% ITS similarity, whereas C. ploettneriana could not be connected to a smut-like anamorph. Ciboria ploettneriana in the here-redefined sense clustered in our combined phylogenetic analyses of ITS and LSU in relationship of Sclerotinia s.l., Botrytis, and Myriosclerotinia rather than Ciboria, but its placement was not supported. Its affiliation in Ciboria was retained until a better solution is found. Also Schroeteria poeltii clustered unresolved in this relationship but with a much higher molecular distance. The remaining three Schroeteria spp. formed a strongly supported monophyletic group, here referred to as “Schroeteria core clade”, which clustered with medium to high support as a sister clade of Monilinia jezoensis, a member of the Monilinia alpina group of section Disjunctoriae. We observed ITS distances of 5–6.3% among members of the Schroeteria core clade, but 13.8–14.7% between this clade and S. poeltii, which appears to be correlated with the deviating chlamydospore morphology of S. poeltii. Despite its apparent paraphyly, Schroeteria is accepted here in a wide sense as a genus distinct from Monilinia, particularly because of its very special anamorphs. A comparable heterogeneity in rDNA analyses was observed in Monilinia and other genera of Sclerotiniaceae. Such apparent heterogeneity should be met with skepticism, however, because the inclusion of protein-coding genes in phylogenetic analyses resulted in a monophyletic genus Monilinia. More sclerotiniaceous taxa should be analysed for protein-coding genes in the future, including Schroeteria. Four syntype specimens of Ciboria ploettneriana in B were reexamined in the present study, revealing a mixture of the two species growing on V. hederifolia agg. Based on its larger ascospores in comparison with S. decaisneana, a lectotype is proposed for C. ploettneriana.

Rediscovery of Hemitrichia leiocarpa (Trichiales, Myxomycetes) in Brazil

Abstract Hemitrichia leiocarpa was collected in the state of Pernambuco, northeastern Brazil, in 1968, and five decades passed before its second collection in the country. The species was rediscovered in the Pedra Talhada Biological Reserve, municipality of Quebrangulo, state of Alagoas, 225 km from the first location. A description of specimens that sporulated in moist chamber culture prepared with ground litter and deposited in the Myxomycetes collection of the UFP Herbarium is provided. Detailed and updated information on the worldwide geographical distribution of the species is provided, as well as information on substrates and microhabitats based on bibliographic sources and herbarium catalogues. The species can be considered near threatened (NT) based on IUCN criteria and its inclusion in the Brazilian Red List of Threatened Species is recommended.

Spatiotemporal distribution and dynamic changes of myxomycetes in subtropical forests of China

The spatiotemporal distribution and dynamic changes of species composition of myxomycetes in humid subtropical forests of Houhe National Nature Reserve in southern China were studied by collecting samples of bark and ground litter within four seasons for isolation of myxomycetes in moist chamber cultures and by collecting fruiting bodies in the field from June to October. A total of 725 specimens of myxomycete fruiting bodies representing 77 species of 25 genera were registered, among them 302 records/51 species from field collections and 423 records obtained from 600 moist chamber cultures of ground litter and bark of living trees, which resulted in 35 and 39 species, respectively. Cornuvia serpula and Perichaena microspora were recorded for the first time in China. Both myxomycete species richness and diversity were significantly different in ground litter among sites and field collections among months. NMDS combined with Permanova indicated that the site had a greater impact on the myxomycete community of bark and litter than the season, while the month of field collections had a greater impact than the sampling sites. CCA and VPA analysis showed that the bark-inhabiting myxomycete species were mainly affected by spatial variables, while the litter-inhabiting and field collected species were more affected by climatic factors.

A New Myxomycetes record (Myxogastria) from Turkey: Didymium listeri Massee

Myxomycetes called Plasmodial slime moulds, or true slime molds are eukaryotic microorganisms. They live in a variety of ecosystems. Genus Didymium Schrad. (family Didymiaceae) is a myxomycete taxon containing calcareous peridia (order Physarida) and non-calcareous capillitium. Didymium listeri Massee were recorded in this study for the first time from Turkey. D. listeri sporocarp was found in the laboratory by moist chamber culture. In addition, the description, distribution, photograph and identification key of the taxon were presented.

Distribution and diversity of myxomycetes in Tiantangzhai National Forest Park, China.

Although myxomycetes are ubiquitous in terrestrial ecosystems, studies on their distribution and diversity in subtropical humid forests are still lacking. Field collections and moist chamber cultures were conducted from May to October within a two-year period in the Tiantangzhai National Forest Park of China. A total of 1,492 records representing 73 species belonging to 26 genera were obtained, of which 243 records/37 species were from field collections, and 1,249 records/52 species were from moist chamber cultures. Among the specimens obtained by culturing, 896 records/38 species and 353 records/37 species were obtained from living bark and ground litter, respectively. ANOVA showed that the sampling months had significant impacts on collection of myxomycetes from field and those that inhabit litter. An LEfSe analysis indicated that Arcyria was significantly abundant in August, while Stemonitis and Physarum were more abundant in July when collected from field. An RDA analysis showed that temperature was the main factor that affected the litter-inhabiting myxomycetes. The ANOVA indicated that forest type was the significant factor for bark-inhabiting myxomycetes. Diderma effusum was primarily obtained from mixed forests, while Clastoderma debaryanum and Colloderma oculatum were more common in coniferous forests. The RDA analysis indicated that the vegetation, pH, water retention, and elevation were the primary factors that affected the bark-inhabiting myxomycetes.

<strong>Five new Myxomycetes (Myxogastria) records from Turkey</strong>

Myxomycetes samples were obtained from Adana and Hatay provinces of Turkey. As a result of field and laboratory studies five myxomycetes species are reported as new records. Three of the new records (Arcyria cerradensis, Craterium aureonucleatum and Diderma spumarioides) were found as natural sporophore in the area. The other two species (Cribraria spinispora and Perichaena quadrata) were grown in the laboratory by moist chamber culture method. Short descriptions, habitats, localities, collection dates, fungarium numbers and images of the taxa are given. This work has contributed to Myxobiota of Turkey.