Effect of Selected Entomopathogenic Fungal Species on Embryonic Development of Ascaris suum (Nematoda)

The aim of the study was to evaluate the potential of using five selected species of entomopathogenic fungi (Beauveria bassiana, B. brongniartii, Conidiobolus coronatus, Isaria fumosorosea, and Metarhizium robertsii) in the bioregulation of the dispersive stages of the parasitic nematode-Ascaris suum. Experimental cultures of each of the selected entomopathogenic fungi, as well as a control culture without fungi, were incubated with A. suum eggs at 26 °C for 28 days. Development of the A. suum eggs was observed using a light microscope on the 7th, 14th, 21st, and 28th days of incubation. The API-ZYM® test was used to determine, semiquantitatively, the activity of 19 hydrolytic enzymes from the entomopathogenic fungi. The cytotoxicity of the fungi was determined using tetrazole salt MTT. It was found that none of the five tested strains of entomopathogenic fungi showed an ovicidal effect, and none of them colonized the A. suum egg shells. However, ovistatic activity was observed mainly until the 14th day of incubation by I. fumosorosea, M. robertsii, and B. bassiana. In the MTT test, M. robertsii showed moderate cytotoxicity, while the other species showed low cytotoxicity. Among the strains tested, I. fumosorosea showed the highest spectrum of hydrolase production (13 out of 19 enzymes gave a positive reaction from 3 to 5; 20-40 nM or more). The absence of morphological changes in the A. suum egg shells suggests that the antagonistic effect of the studied entomopathogenic fungi may be due to their cytotoxicity, associated with the production of secondary metabolites-toxins (M. robertsii) and enzymatic activity (I. fumosorosea).

The Application of Spray-Dried and Reconstituted Flaxseed Oil Cake Extract as Encapsulating Material and Carrier for Probiotic Lacticaseibacillus rhamnosus GG

Agro-industrial by-products are promising source of biopolymers, including proteins and polysaccharides. This study was designed to evaluate the flaxseed oil cake extract (FOCE) as natural encapsulating material and carrier for probiotic Lacticaseibacillus rhamnous GG (LGG). The powders were obtained using three spray drying inlet temperatures (110 °C, 140 °C, 170 °C), and reconstituted. The influence of temperature on water activity, morphology, chemical composition, flowability and cohesiveness of the powders was estimated. For all variants, the survival of bacteria during spray drying, and simulated passage through the gastrointestinal tract was evaluated. The preservation of LGG probiotic features such as cholesterol reduction, hydrophobicity and adhesion to mucin were examined. Results revealed that all physicochemical and functional characteristics of the powders were affected by the inlet temperature. This study demonstrated that FOCE is an appropriate matrix for spray drying (due to flaxseed proteins and polysaccharides) providing high survivability of bacteria (89.41-96.32%), that passed meaningfully through the simulated gastrointestinal tract (4.39-5.97 log reduction), largely maintaining their probiotic properties, being a promising environmentally-friendly carrier for probiotic LGG.

Updated Distribution of Endangered Psathyrella ammophila in Poland – New Localities on Wolin Island

<em>Psathyrella ammophila </em>is a psammophilous fungus most frequently inhabiting seashore beaches, sand dunes and sandy inland areas. Although it is a widely spread species, in some countries it is rare or threatened, including Poland, where it is classified as “endangered” (E). In Poland, <em>P. ammophila </em>has been found in 26 localities, including 14 new reports after 1970. We present two new Polish localities from white sand dunes at the western shore of the Baltic Sea (Wolin Island). Moreover, ecological information and macroscopic and microscopic features of the basidiocarp based on collected samples are presented. The problem of the disappearance of dunes as a primary habitat of <em>P. ammophila </em>is also discussed.

The influence of tin ions on growth and enzymatic activity of entomopathogenic fungi

In this in vitro study, the influence of tin ions at concentrations of 1–1,000 ppm on the development and enzymatic activity of four entomopathogenic fungi (<em>Beauveria bassiana</em>, <em>B. brongniartii</em>, <em>Isaria fumosorosea</em>, and <em>Metarhizium robertsii</em>), that are commonly used in biological plant protection, are examined. Each of the fungal species tested reacted differently to contact with the Sn²⁺ ions at the tested concentrations. Exposure to Sn²⁺ ions affected the rate of development, morphology, and enzymatic activity of fungi. Of the four fungal species studied, <em>M. robertsii</em> was the most resistant and showed complete growth inhibition at the highest Sn²⁺ concentration tested (1,000 ppm). For the other entomopathogenic fungi, the fungicidal effect of Sn²⁺ ions was noted at the concentration of 750 ppm. Exposure to Sn²⁺ ions (up to 500 ppm) resulted in enhanced biochemical activity; and all entomopathogens that were tested showed increased production of <em>N</em>-acetyl-β-glucosaminidase (NAG) as well as several proteases. Moreover, <em>B. brongniartii</em> and <em>M. roberstii</em> showed increased lipases synthesis. These changes may increase the pathogenicity of the fungi, thereby making them more effective in limiting the population of pest insects. The exposure of the entomopathogenic fungi to a medium containing Sn²⁺ ions, at concentrations that were appropriate for each species, induced hyperproduction of hydrolases, which might be involved in aiding the survival of entomopathogenic fungi in the presence of heavy metals. This study shows that the fungistatic effect of Sn²⁺ on entomopathogenic fungi did not restrict their pathogenicity, as evidenced by the stimulation of the production of enzymes that are involved in the infection of insects.

The Ovistatic Effect of Saprotrophic Soil Fungi on Ascaris suum Eggs

The aim of the study was to evaluate the potential use of selected species of soil fungi (Fusarium oxysporum, F. sulphureum, F. verticillioides, and Penicillium expansum) for the bioregulation of the dispersive stages of a parasitic nematode – the large roundworm of pig (Ascaris suum). Experimental cultures containing A. suum eggs with soil fungi and control cultures without fungi were incubated at 26°C for 28 days. Microscopic observations of the developmental stages of the A. suum eggs (zygote, 2-8 blastomeres, morula/blastula, gastrula, and larva) were performed at 7, 14, 21, and 28 days. The API-ZYM test was used to semi-quantitatively determine the activity of 19 hydrolytic fungal enzymes. The cytotoxicity of the fungi was determined with a tetrazole salt MTT assay. Microscopic observations of A. suum eggs incubated in the presence of fungi up to day 28 did not show any signs of destruction to egg shells and/or penetration of the fungi into the eggs. The ovistatic effect of all tested fungi (F. sulphureum, P. expansum, F. verticillioides, and F. oxysporum; p<0.05) was seen only on the 7th day of incubation, whereas on the 14th day, only F. verticillioides and F. oxysporum showed an inhibitory effect on the embryogenesis of A. suum, and by the 28th day, only P. expansum. The API-ZYM test showed differences in the hydrolytic activity of the tested strains, while the MTT assay showed the high cytotoxicity of F. sulphureum, the moderate cytotoxicity of F. verticillioides and P. expansum, and the low cytotoxicity of F. oxysporum. Among the fungal strains studied, F. sulphureum showed the highest ovistatic effect, which may be related to its enzymatic activity and cytotoxicity.

Microscopic fungi on Schoenoplectus lacustris in Płociczno and Płociowe lakes in Drawa National Park (northwest Poland)

In the period 2009–2011, the micromycetes causing symptoms on the leaves of <em>Schoenoplectus lacustris</em> (SL) from Płociczno and Płociowe lakes in Drawa National Park (DNP) were investigated. A total of 39 taxa of microscopic fungi and chromistan fungi were found. The taxonomic structure of the mycobiota was dominated by anamorphs of Ascomycota. In each year of the study, the SL fungal species richness was higher in Płociowe Lake than in Płociczno Lake. In all the years of study in both lakes, the fungal community on SL was composed of the following six dominant species: <em>Alternaria alternata</em>, <em>Cladosporium herbarum</em>, <em>Fusarium incarnatum</em>, <em>F. sacchari</em>, <em>Gibberella avenacea</em>, and <em>Pleospora scirpicola</em>. The species occurring exclusively in Płociczno Lake were <em>Papulaspora immersa</em>, <em>Puccinia scirpi</em>, and <em>Trichothecium roseum</em>, and those found only in Płociowe Lake were <em>Acremoniella atra</em>, <em>Alternaria atra</em>, <em>Aspergillus niger</em>, <em>A. versicolor</em>, <em>Fusarium oxysporum</em>, <em>Gonatobotrys simplex</em>, <em>Massariosphaeria scirpina</em>, <em>Microascus brevicaulis</em>, <em>Penicillium chrysogenum</em>, and <em>Stagonospora aquatica</em>. Only one confirmation of the occurrence of <em>Puccinia scirpi</em> and the lack of other specialized obligate parasites indicate the good health of SL in DNP. The facultative parasites, inter alia, <em>Boeremia exigua</em>, <em>Chaetomium globosum</em>, <em>Fusarium culmorum</em>, <em>F. incarnatum</em>, <em>F. sacchari</em>, <em>Gibberella avenacea</em>, and <em>Stagonospora aquatica</em> that are present on plants as part of the natural process of apoptosis may influence the health of SL.

Microscopic fungi on Nymphaeaceae plants of the Lake Płociczno in Drawa National Park (NW Poland)

<p>The aim of this study was to determine the occurrence of micromycetes associated with disease symptoms on the leaves and flowers of three plant species, <em>Nymphaea alba</em> (NA), <em>Nymphaea candida</em> (NC), and <em>Nuphar lutea</em> (NL), forming nympheid phytocoenoses on Lake Płociczno in Drawa National Park during the years 2009 to 2012. From all collected plant specimens, an overall number of 38 distinct taxa of fungi and chromistan fungal analogues was isolated. The largest diversity of taxa was found on NL (37 taxa), the lowest was on NC (4 taxa), and NA contained 12 taxa.</p><p>Each year, anamorphic forms of Ascomycota were dominant in the taxonomic structure. For the first time in Poland, <em>Septoria nupharis</em> (NA, NL, NC) and <em>Colletotrichum nymphaeae</em> (NL, NC) were found on their spotted leaves. For both of the mentioned pathogens, <em>Nymphaea candida</em> is a new host plant in Poland. <em>Botrytis cinerea</em>, <em>Elongisporangium undulatum</em> (= <em>Pythium undulatum</em>), <em>Epicoccum nigrum</em>, <em>Fusarium incarnatum</em> (= <em>F. semitectum</em>), and <em>Gibberella avenacea</em> (= <em>Fusarium avenaceum</em>) were found each year in the studied phytocoenoses. The confirmation of NA and NL flower infections by <em>Botrytis cinerea</em>, which leads to gangrene, is an important aspect of the gray mold epidemiology. Until now, the occurrence of smut fungi on nympheids in Drawa National Park was not observed. The taxonomic structure and the predomination of asexual stages of fungi, as well as the similarity coefficients, suggest that the seasonal decomposition of nympheids run naturally and contribute to maintaining the stability of the lake ecosystem.</p>

Mycological and palynological studies of early medieval cultural layers from strongholds in Pszczew and Santok (western Poland)

<p>Cultural layers from early medieval strongholds in Pszczew and Santok have been examined for the presence of pollen grains and spores as well as residues of fungi. The presence of the following remains has been recorded: fossil hyphopodia of <em>Gaeumannomyces</em>, teliospores of <em>Puccinia</em>, spores of <em>Bipolaris</em>, <em>Thecaphora</em> and <em>Tilletia</em>, teliospores of the genus <em>Urocystis</em>, <em>Ustilago</em> and <em>Uromyces</em>, ascocarps (perithecium) of the Ascomycota or the pycnidium of Sphaeropsidales. A greater diversity and abundance of fungi spores sensu lato was recorded in Santok, as compared to Pszczew. Both early medieval sites recorded a significant proportion of cereal pollen, including <em>Secale cereale</em>. It remains an undisputed fact that the grains and other plants collected in both strongholds were strongly infected with fungi. The analysis of the cultural layers for the presence of fungi remains provides significant data on the presence of certain species of plants and their growth conditions in natural environments and in agriculture.</p>

Effect of Penicillium frequentans and Stachybotrys chartarum on respiratory metabolism of developing eggs of Ascaris suum (Nematoda)

Effect of saprotrophic soil fungi <i>Penicillium frequentans</i> and <i>Stachybotrys chartarum</i> on respiratory metabolism of <i>Ascaris suum</i>, during its embryogenesis was determined using histoenzymatic methods. Based on histochemical assessment of the enzyme actvity (glycolysis-lactate dehydrogenase-LDH; tricarboxylic acid cycle-succinate dehydrogenase-SDH) changes in the energy metabolism of developing eggs of <i>A. suvm</i> were detected. Of the fungi species tested - <i>P. frequentans</i> caused the most extensive disorders in the processes of cellular oxidation, which were manifested in a decline of SDH activity during gastrulation. Incubation of eggs of Ascaris with mycelia of both fungi: <i>S. chartarum</i> and <i>P. frequentans</i> - in lesser extend affected respiratory metabolism in embryogenesis of this nematode.

Effect of some saprotrophic soil fungi on the embryonic development of Ascaris suum (Nematoda)

Effect of <i>Penicillium frequentans</i> and <i>Stachybotrys chartorum</i> fungi on the embryonic development of <i>Ascaris suum</i> were studied in the present paper. In eggs that were incubated with fungi, significant delay of initiation of zygote division, as well as retardation of the development of individual stages of embryogenesis, was given a closer insight. Additionally, the following phenomena were observed: vacuolisation of zygote and disturbances in the distribution of yolk, non-synchronous and unequal divisions of blastomere, deformations of the blastula, gastrula, and larval stages. The above changes were more distinct in eggs that were incubated with <i>P. frequentans</i>. In the cultures with <i>P. frequentans</i>, a significantly lower number of larvac, as well as their earlier mortality were observed.

Influence of excretions of chosen Penicillium species on the population of Globodera rostochiensis

It was stated that the contact of <i>Penicillium frequentans</i> and <i>P. verrucosum</i> var. <i>cyclopium</i> with <i>Globodera rostochiensis</i> in the medium stimulated reduction in the number of cysts of nematodes. Among 16 <i>P. verrucosum</i> var. <i>cyclopium</i> metabolites the strongest destruction of eggs and larvae in <i>G. rostochiensis</i> cysts was observed in the case the R_r = 0.31 and R_r = 0.75 substances. The above metabolites caused that irregular lipid-like granules formed in the intestine tracts of the <i>G. rostochiensis</i> larvae. Most probably, the pathological presence of lipides in the intestine resulted from the distemper of synthesis of lipolythic enzymes in the nematodes under the effect of the <i>P. verrucosum</i> var. <i>cyclopium</i> extracts.

Comparison of the effect of the chosen species of saprotrophic fungi on the development of Toxocara canis and Ascaris suum eggs

The study aim was to compare the antagonistic interaction between saprotrophic soil fungi and embryonic development of geohelminths Toxocara canis and Ascaris suum. The experimental cultures were fertilized eggs of T.canis and A. suum incubated together with mycelium of strains: Fusarium culmorum, Metarhizium anisopliae,Paecilomyces fumosoroseus, Trichoderma viride and Trichothecium roseum. In the control cultures the eggs of both nematode species were incubated without fungi. The experiment was conducted at temp. 26°C for 60 days. Compared with the control, all of the tested species of fungi significantly extended the embryonic development of both T. canis and A. suum. Most inhibitory effect on the rate of embryonic development of T. canis and A. suum had three fungal species: P. fumosoreus, M. anisopliae and T. viride. Compared with the control, on the 60th day of incubation in the presence of each of the tested fungal species, a larger percentage (p<0.05) of morphological abnormalities was stated in developing embryos of T. canis (49–69%) than in A. suum (15.1–67.7%). Among the examined fungal species, only incubation with P. fumosoroseus resulted in significantly greater (p<0.05) incidence of embryonic malformations(embryopathies) in T. canis, as compared with A. suum. Also the percentage of dead larvae of T. canis in the control and in cultures with fungi (12% and 100%, respectively) was significantly higher in comparison with A. suum (0.5% and 10.3–36%, respectively). The highest percentage of non-viable larvae of A. suum was found in the presence of P.fumosoroseus, and the lowest in the presence of M. anisopliae. Findings may indicate that T. canis eggs are more sensitive to antagonistic interaction of the examined fungal strains than A. suum eggs.

Parasites of zooplankton and periphyton assemblages in the littoral zone of lakes in Drawa National Park, Poland

Studies on parasitism in zooplankton and periphyton assemblages were carried out on samples of water collected from Lakes Płociczno and Płociowe in the Drawa National Park in 2008-2011. Occurrence of the fungal mycobiotal and protozoan parasites of invertebrates was recorded in both lakes. Parasitism of <em>Chydorus </em>sp. (Cladocera) by <em>Saprolegnia </em>sp. occurred on 0.8% of individuals of the host population, of <em>Brachionus calyciflorus </em>(Rotifera) by <em>Microsporidium </em>sp. on 1.2% of the host population, and of Nematoda members by <em>Pythium </em>sp. on 5% of the host population. Parasites were recorded only in springtime.

Studies on toxicity of selected Oomycetes

The MTT test is used to determine the cytotoxicity of species: <em>Achlya americana, A. caroliniana, Leptomitus lacteus, Saprolegnia ferax</em> and <em>S. lapponica</em>, which occurred in Lake Sitno in the Drawieński National Park (W Poland). It was stated that among five examined species of zoosporic fungi only one of them <em>A. caroliniana</em>, does not show cytotoxic effect. Low and mean toxicity of other tested water FLO, however, combined with the large-scale character of their appearance shows, that they can create serious threat for the spawn, fry, fish as well as the other organisms (including invertebrates) existing in water.

Studies on phytopathogenic and saprotrophic fungi in rush associations of Lake Glinno (NW Poland)

During the vegetation seasons in years 2004-2005 the health state of rush plant species from <em>Phragmition</em> and <em>Magnocaricion</em> alliances around the Lake Glinno was investigated. From 13 plant species with disease symptoms 94 species of fungi and FLO were isolated. The highest mycological biodiversity was stated in <em>Phragmitetum australis</em> (24 species) and <em>Thelypteridi-Phragmitetum</em> (27 species) plant associations. The host species in which the biggest number of fungi and FLO species was observed were: <em>Phragmites australis</em> (37 species) and <em>Carex acutiformis</em> (25 species). The highest mycological similarity based on the Jaccard-Sörensen coefficient occurred between <em>Caricetum acutiformis</em> and <em>Glycerietum maximae</em> plant associations (50%) whereas the lowest value of the coefficient represented <em>Glycerietum maximae</em> and <em>Phalaridetum arundinaceae</em> associations (7%).

[Antagonistic interactions between saprotrophic fungi and geohelminths. 2. Saprotrophic fungi in biocontrol of parasitic geohelminths of humans and animals]

The soils ecosystem plays an important role in the epidemiology of geohelminth diseases of humans and animals. Soil contamination with ova of the parasitic geohelminths represents a global public health-hazard issue. Biological agents have been thought to control the infective forms of parasites present in the soil. Biocontrol of geohelminths represents an alternative to pesticides (i.e., nematicides), which are not efficient in killing infective nematode forms and, additionally, result in the environment pollution and long-term disturbances in the soil ecosystem homeostasis. The degree of the inhibiting effect of soil saprotrophic fungi on geohelminth embryonic development varies and depends on the species. A number of fungi cause various morphological disorders in the embryos of developing parasitic nematodes, but also have an ovicidal effect. Although the nature of the antagonism between fungi and other living organisms has not been fully explained, it is certain that mycotoxins and fungal enzymes constitute its important components. Considering the studies carried out so far, the antagonistic effect of mold fungi against the infective stages of geohelminths can be fully recommended as a real control factor, especially as these saprotrophs represent a natural factor within the soil environment, that is of particular biochemical activity.

[Antagonistic interactions between saprotrophic fungi and geohelminths. 1. Saprotrophic fungi in the biological control of phytopathogenic geohelminths]

The state of knowledge on the possible antagonism between soil saprotrophic fungi and phytopathogenic nematodes of the genera Meloidogyne, Heterodera, and Globodera is reviewed basing on the literature and our own research. Mycelial colonisation of various developmental stages of these geohelminths is the most common factor thought to reduce their populations in nature. The following parasitic fungi can be found on the cysts, eggs, as well as the larvae of the nematodes: Paecilomyces lilacinus, Verticillium chlamydosporium, Cylindrocarpon destructans, Pochonia chlamydosporia, Fusarium spp., and Penicillium spp. The fungi invade the nematodes, such as Heterodera, Globodera, or Meloidogyne, "passively" penetrating through the natural orifices of the cysts, eggs, and larvae of the host. Equally frequent, however, is a biochemical action of the fungi prior to colonisation, which is linked with production of mycotoxirls or hydrolytic enzymes. Such an active way of fungal penetration of various stages of the phytopathogenic nematodes has been observed in Pochonia chlamydosporia, Penicillium verrucosum var. cyclopium, P. frequentans, Sclerotinia rolfsii, Rhizoctonia solani, and Fusarium spp. Triacylglycerols (TAG), phenols, as well as trichothecene, T-2, have been found in the metabolites extracted from mycelia of these species. Predation by fungi is also a factor that may reduce a population of phytopathogenic nematodes. This form of antagonism is characteristic for nematicidal fungi of the genera Arthrobotrys and Dactylella. These fungi form shrinking rings and hooks in their mycelia by which the fungus entangles and paralyses a migrating form of nematode. Despite the fact that the antagonism between fungi and nematodes is a commonly occurring phenomenon observed in the soil, the nematicidal and nematotoxic properties of fungi have not a wide application in biological plant protection. Up till now, only the bionematicides based on Arthrobotrys robusta (Royal 300 and Royal 350) as well as Paecilomyces lilacinus (Biocon and PL Plus) have found its commercial application.

[The influence of the Metarhizium fungi on the embryonic development of Ascaris suum]

PURPOSE

The present study focused on the effect of two fungal species Metarhizium flavoviride and Metarhizium anisopliae on the embryonic development and viability of Ascaris suum larvae.

RESULTS

Microscope examination revealed that the presence of the mycelium inhibited the egg development, compared to control. The fungus-exposed eggs featured zygote vacuolisation, irregular blastomere cleavage, and morphological disturbances in the stages of blastula, gastrula, and larva. The embryopathies were significantly more frequent in the eggs incubated with M. flavoviride. Also the mortality of the developed larvae was significantly higher after 60-day culture with M. flavoviride.