Generation of myxomycete data from three discrete experiments using moist chamber cultures in a Neotropical forest

The moist chamber technique is widely used in ecological research on myxomycetes.However,limited assessments on the usefulness of the technique have been carried out using empirical data.In the present study,three discrete experiments were carried out in a tropical forest in Costa Rica with the main objective of providing meaningful parameters for the design of future studies in similar environments.All three experiments showed that results could be maximized for representativeness by designing studies that purposedly target ecological components of the studied system.In a comparison of recorded data at three heights above the forest ground,a significantly higher number of records and species were observed in the higher vertical partitions,suggesting that collecting research material from the ground,in this ecological setting,reduces the probability of recording the highest species diversity.However,the ground level was associated with a high number of records and species within the genus Didymium,offering relevant information for studies targeting this genus.Similarly,based on effort,results from the present study suggest that a collecting effort designed to record system variability represents a superior cost-benefit situation for synecological studies than a more intense effort designed only for a limited spatial or temporal space,which in turn would reduce the ecological significance of the resultant data.

Myxomycete colonization on translocated and non-translocated dead leaves from temperate and tropical forests

Samples of dead leaves on the forest floor were collected from a locality in central Costa Rica and another locality in northwest Arkansas in the United States and then were placed in fine-mesh nylon bags,autoclaved and left out in the field for four months.Half of the bags prepared with sterile material from each country were placed out in the country where they were collected,and the other half were placed in the other country.A characterization of forest structure and ground leaf chemistry was carried out for both localities and both leaf types.When recollected,all samples were processed for myxomycetes with the use of the moist chamber culture technique.The cultures yielded a total of 156 records of myxomycetes representing 16 species,but only 13 records and six species were isolated from the samples left out in Costa Rica.One hundred percent of cultures placed out in Arkansas produced myxomycetes,whereas only 68%of those placed out in Costa Rica were positive for these organisms.Differences in species richness and number of records were observed across forests where the samples were placed out,and no differences were observed based on the origin of the leaves.Results suggested that myxomycete colonization in the studied areas is primarily affected by the dynamics of the forest type and secondarily by substrate attributes.Some myxomycete species recorded on leaves with poorer chemical values are also consistent with field data.In the present study,the more open character of the temperate forest in Arkansas without a film of water layer covering the leaves on the ground seemed to have played a role in the establishment of myxomycete propagules in the sterile material during the time of the investigation.