Fuligo Septica Research Articles

Behavior of the Inner Wall Layer of the Germinating Fuligo septica Spore: Evidence of Peroxidase Activity

Behavior of the Inner Wall Layer of the Germinating Fuligo septica Spore: Evidence of Peroxidase Activity

Spore germination and swarm cell morphogenesis in the acellular slime mold Fuligo septica

This report describes conditions under which spores of the acellular slime mold Fuligo septica underwent a very rapid, synchronous and complete (100%) germination followed by morphogenesis of motile, flagellated swarm cells from the released protoplasts. This developmental sequence was initiated immediately upon wetting the spores with a surfactant and was completed within 40–50 min in the absence of any exogenous nutrient other than sodium phosphate buffer. Oxygen was required for germination. The rate and percentage of germination diminished with increasing spore concentration suggesting the existence of an autoinhibitor. The morphological sequence of events in the differentiation process was examined by scanning electron microscopy.

Patterns of occurrence of myxomycetes in a spruce forest in South Sweden

A 4‐yr field study was carried out on selected species of myxomycetes. Reticularia jurana, Symphytocarpus flaecidus, Amaurochaete atra, and A. tubulina occur predominantly in May–June. Ceratiomyxa fruticulosa, Stemonitis axifera, S. fusca, S. hyperopta, and Fuligo septica in June–August, and Colloderma oculatum, Trichia botrytis, T. decipiens, and Fuligo muscorum in September–October. Lycogala epidendrum may occur from May to October. Whereas several species seem to be restricted to late autumn, those appearing in spring and early summer are occasionally found also later in the season. Many species with large plasmodia are rare under arid conditions. Complex factors probably influence spore germination, and it is often impossible to explain a sudden abundance of a species merely from temperature and precipitation. Several species show clear substrate preferences. Plasmodia may develop in cavities in wood and then move out to the surface to fructify. Insects are probably important for the dispersal of several species. Invertebrates, among them snails, are predators on plasmodia as well as on fructifications.

Spore Germination in the MyxomyceteFuligo Septica: Evidence for the Existence of a Soluble Autocatalytic Factor

Fuligo septica spores in mass suspensions germinate with logarithmic kinetics, indicating that spore germination is a complex, controlled phenomenon and not random. Spores germinate at higher rates...

Taxonomic Significance of Intraspecific Isozyme Patterns of the Slime Mold Fuligo septica Produced by Disc Electrophoresis

Taxonomic Significance of Intraspecific Isozyme Patterns of the Slime Mold Fuligo septica Produced by Disc Electrophoresis

TAXONOMIC SIGNIFICANCE OF INTRASPECIFIC ISOZYME PATTERNS OF THE SLIME MOLD FULIGO SEPTICA PRODUCED BY DISC ELECTROPHORESIS

Plasmodial extracts of 45 isolates of Fuligo septica (L.) Wiggers selected from diverse geographical areas were subjected to acrylamide disc electrophoresis. Profiles for ten enzymes and general protein were determined. Profile variability among isolates occurred. Indices of similarity calculated for each isolate indicated that the variations of the yellow and white plasmodial isolates fell within different ranges. Determination of the total range of variation for the species must wait on the analysis of more white isolates. The extreme sensitivity of disc electrophoresis in detecting color forms suggests it can be useful as a tool in myxomycete taxonomy.

THE FATTY ACID COMPOSITION OF PLASMODIUM AND SPORANGIUM OF TRUE SLIME MOLDS

The fatty acid composition of plasmodia of slime molds, Fuligo septica, Perichaena colticalis, and Badhamia sp., is very similar. The most abundant are oleic and linoleic acids. The composition of fatty acids in sporangia and plasmodia of Fuligo septica was found to be different in that the former contains far less 16:0 and more 20:1(11) than the latter. Furthermore, the former contains an unidentified acid which is lacking in the latter.

Effect of Aeration on the Germination of Fuligo septica Spores

Effect of Aeration on the Germination of Fuligo septica Spores

Effect of Aeration on the Germination of Fuligo Septica Spores

(1971). Effect of Aeration on the Germination of Fuligo Septica Spores. Mycologia: Vol. 63, No. 3, pp. 669-671.

PRELIMINARY INVESTIGATION OF THE DOUBLE‐DIFFUSION TECHNIQUE AS A TOOL IN DETERMINING RELATIONSHIPS AMONG SOME MYXOMYCETES, ORDER PHYSARALES

Double‐diffusion technique was used to investigate myxomycete relationships within the order Physarales. Extracts of plasmodia of 22 slime mold isolates were reacted with five antisera produced to Plasmodia of Didymium nigripes, Physarella oblonga, Physarum polycephalum, Physarum gyrosum and Fuligo septica. Two isolates of Fuligo septica tested alike. Four isolates of Physarum pusillum did not test alike, and no valid conclusion of the relationship of this species was possible. These isolates showed strong serological affinity: (1) Physarum gyrosum, Physarella oblonga, two isolates of Fuligo septica, and possibly two isolates of Physarum pusillum, and Physarum tenerum; (2) Physarum polycephalum and Physarum flavicomum; (3) Fuligo septica and many of the species tested; (4) Didymium nigripes and at least one isolate of Didymium iridis. In most cases serologial relationships among species tested did not coincide with current taxonomy based on morphology of fructification.

FIBRILLAR DIFFERENTIATION IN MYXOMYCETE PLASMODIA

Myxomycete plasmodia of four different types (not including Physarum polycephalum) were studied in thin sections viewed in the electron microscope. In the cytoplasm of the protoplasmodia of Clastoderma debaryanum and the phaneroplasmodia of Fuligo septica fixed in situ, fibrillar differentiations of three rather distinct kinds were observed. One of these is filamentous and closely resembles the filaments (or "microtubules") of the mitotic apparatus of other species. The larger phaneroplasmodia of two species belonging to the Physarales and the plasmodium of Hemitrichia vesparium showed fewer and less well defined fibrils, and no fibrils were seen in the aphanoplasmodium of Stemonitis fusca. Good stabilization of such fibrils in larger plasmodia may require fixation methods more rigidly controlled than those which succeed with microscopic protoplasmodia. The function of the observed fibrils cannot yet be determined. Their presence in cytoplasm fixed in situ, however, lends support to those theories of protoplasmic movement which are dependent on integral cross-bonding of one or a few molecular species.

Spore liberation by water drops in some myxomycetes

Spore liberation by falling water drops has been demonstrated in four myxomycetes. In Lycogala epidendrum not only does the aethalium behave as a puff-ball bellows mechanism operated by falling drops, but the ostiole through which the spores escape is itself produced by drop bombardment. In Fuligo septica and Tubifera ferruginosa the aethalium is ruptured by impacting water drops and clouds of spores are released. In Leocarpus fragilis the water drop acts as a crushing agent rupturing the individual sporangia and exposing the spores.

Some observations on the cultivation, fruiting and germination of Fuligo septica.

SUMMARY: Conditions optimal for the laboratory culture of unpurified Fuligo septica plasmodium were examined. The organism was grown in the laboratory for over 2 years, during which time regular sporulation occurred. Investigation of factors which affected sporulation suggested that this was induced by material present in older cultures; light did not precipitate it. Spore germination occurred readily in the laboratory; some experiments on germination were made. F. septica plasmodium was purified by a migration technique combined with antibiotic treatment. Two-member cultures were established with two yeasts and a Penicillium sp. isolated from plasmodium, and with a baker's yeast. Several other organisms (including Gram-positive and Gram-negative bacteria and yeasts) were not satisfactory as associate organisms in two-member cultures. Satisfactory axenic culture was not obtained, slow growth for a few weeks only being obtained on an autoclaved suspension of baker's yeast.

Obtaining the Slime Mold Fuligo septica in Pure Culture*

The slime mold Fuligo septica has been grown bacteria‐free in a pure 1.5% agar and oats at a temperature of 25°C. The Plasmodium was also grown under water.

THE COLOR OF MYXOMYCETE PLASMODIA

THE COLOR OF MYXOMYCETE PLASMODIA

FACTORS INFLUENCING THE GERMINATION OF MYXOMYCETOUS SPORES

While studying the spore germination of certain Myxomycetes (5), the writer became impressed with the great variability in his results, not only in the case of different species but also among various gatherings of the same species. For example, spores of some specimens of Enteridiitm Rozeanum (Enteridium splendens) showed a high percentage of germination while those of others germinated poorly or not at all. This variability becomes even more apparent when the results of several investigators are compared. For example, although Jahn (6) obtained no germination with Fuligo septica, Stemonitisfusca, and Lycogala epidendrum, two other investigators, DeBary (i) and Constantineau (3), were successful in securing a high percentage of germination in these species. Constantineau had good results in the case of Cribraria and Dictydium, spores of which DeBary failed to germinate. DeBary obtained germination in Arcyria denudata and Hemitrichia vesparium while Constantineau was unsuccessful with these as well as with Didymium difforme, a species which Jahn and DeBary found to germinate very well. The writer in the past five years, working with fifty-six species and varieties collected in New England (4), has been able to compare his results with those of the authors mentioned above, and as might be expected, finds they agree in some cases and disagree in others. Differences in results possibly may be due partly to a lack of sufficient material from which to draw conclusions, for neither DeBary, Jahn, nor Constantineau state how many gatherings of a species were made nor whether their results were based on observations of more than a single gathering. Some species such as Tubifera ferruginosa, so far as is known, have never been successfully germinated in the laboratory, while spores from various collections of other species give a wide variation in the percentage of germination. The latter fact is shown in the following cases from the writer's observations. Spores of one gathering of Dictydiutm cancellatum showed a germination of one hundred percent while spores of another gathering of the same species showed but thirty to thirty-five percent under the same conditions. Numerous collections of Lycogala epidendritm Contribution no. 98 from the Cryptogamic Laboratories of Harvard University. 280

On the Occurrence of Biflagellate Swarm Cells in Certain Myxomycetes

While the swarm cells of Myxomycetes have almost invariably been described as uniflagellate, occasionally swarmers with two flagella have been reported, associated with normal swarm cells. These biflagellate forms are of two types, the first being characterized by having two flagella at the anterior end and the second by having one flagellum at each end. Swarm cells of the first type, as far as the writer has been able to ascertain, have been recorded only by DeBary * who observed them in a culture of the spores of Trichia varia. Swarm cells of the second type however, are of more frequent occurrence, Constantineau2 having found them in cultures of the spores of Dictydium cancellatum, Durand,3 of Enteridium Rozeanum, and DeBary,1 of Fuligo septica and Trichia varia, in which, as above indicated, they were associated with swarm cells of the first type. While studying spore-germination4 in many representative genera and species of Myxomycetes, the writer also has observed biflagellate swarm cells. Both types occurred in his cultures, which were made by sowing the myxomycetous spores in distilled water in Syracuse glasses. Swarm cells of the first type, that is with two flagella at the