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Mark-recapture studies on co-occurring Sympecma fusca (Vander Linden, 1820) and S. paedisca (Brauer, 1877) (Odonata: Zygoptera: Lestidae)

100%

Brockhaus T.

Polish Journal of Entomology

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2014

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tom 83

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nr 3

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Benefits of low-intensive grazing: co-occurrence of umbelliferous plant (Hladnikia pastinacifolia Rchb.) and opilionid species (Phalangium opilio. L) in dry, calcareous grassland

84%

Sajna N., Kusar P., Slana Novak L., Novak T.

Polish Journal of Ecology

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2011

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tom 59

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nr 4

The impact of grazing has been discussed in many organisms, and it has been shown that it has considerable influence on the structural variation of vegetation, resulting in its tussocky appearance. Such spatial heterogeneity results in plants formations that facilitate other species by providing safe sites against predation and physical stress. On the Trnovski gozd plateau in western Slovenia, a secondary habitat of the rare, monotypic endemic umbelliferous species, Hladnikia pastinacifolia, was colonized by a relatively isolated population of the wide spread opilionid species, Phalangium opilio. We hypothesized that in this stony pasture, the impact of the structurally heterogenous vegetation that results from low-intensity grazing benefits both species on hot summer days. For this purpose, we classified vegetation formation types (VFT) and measured temperature and relative humidity in places settled by Ph. opilio individuals during their daily rest. According to the predominant species, we recognized six VFTs: Carlina acaulis, Ruta divaricata, Koeleria pyramidata, Juniperus communis, understory vegetation and grazed turf. Only the spiny C. acaulis and unpalatable R. divaricata facilitated H. pastinacifolia, while also acting as nurse plants. On the other hand, Ph. opilio preferred the understory, but also settled on the other VFTs, except Ruta. During the highest daily temperature of about 38°C, Ph. opilio avoided the grazed turf. Temperature preferences refer to frequencies of individuals rather than to absolute temperature values. The frequencies were independent of sex and the VFTs. emales were more frequently found in tussocks showing higher temperature profiles (Juniperus, Koeleria). During the hot daytime, Ph. opilio was most sensitive to relative humidity, and less so to temperature, whilst the height of settlement varied in adjusting these two environmental factors. The distribution of males significantly differed between the subsequent morning, midday and evening series, but not between the morning and evening ones, while in females it differed between all the three time series. In habitats, such as stony dry pastures, low grazing intensity can maintain persistent populations of H. pastinacifolia and Ph. opilio even in extremely hot weather. Such grazing is the most convenient measure for protecting both species, especially the highly endangered Hladnikia. The major threat to such habitats is afforestation by Pinus nigra, which deserves additional management. We found that in stony pastures, low grazing intensity assures the structural heterogeneity of vegetation required to maintain persistent populations, of both H. pastinacifolia and Ph. opilio.

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Co-occurrence of pathogenic and non-pathogenic Fusarium decemcellulare and Lasiodiplodia theobromae isolates in cushion galls disease of cacao (Theobroma cacao L.)

84%

Castillo,del D. S., Parra D., Noceda C., Perez-Martinez S.

Journal of Plant Protection Research

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2016

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tom 56

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nr 2

Flowery cushion gall of cacao is a disease complex with six types. Fusarium decemcellulare have been isolated from both flowery and green point galls and recognized as the etiological agent of the disease. In the present work we: i) identified by ITS-rDNA sequencing and/or taxonomy the cultivable fungal species or Operative Taxonomic Units (OTUs) associated with the five symptoms of cushion galls in cacao from Venezuela, and ii) determined the gall inducing capacity on cacao peeled seeds after 45 days of inoculation with suspensions of mycelia/ spores from distinct isolate types. The whole isolate collection rendered an abundance of 113 isolates with a richness of 39 OTUs (27) and eight identified at the species or genera levels, respectively, and in unidentified fungi. The dominant recovered species (≈36%) were F. decemcellulare and Lasiodiplodia theobromae. Some isolates of F. decemcellulare, L. theobromae, F. equiseti, Fusarium spp., F. solani, F. incarnatum, Rhizocthonia solani and Penicillium sp. were pathogenic. Some other isolates of the first six mentioned taxa behave as non-pathogenic. Furthermore, pathogenic and non-pathogenic isolates can also co-occur within a single plant and gall type. Moreover, 2–5 species within a single gall symptom in a single tree were identified (not necessarily at the same point in the tree), indicating a broad diversity of co-occurring taxa.

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Co-occurrence of airborne allergenic pollen grains and fungal spores in Rzeszow, Poland (2000-2002)

84%

Kasprzyk I.

Acta Agrobotanica

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2008

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tom 61

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nr 2

The co-occurrence of airborne allergenic pollen grains and fungal spores was estimated in Rzeszów in the years 2000- 2002. The volumetric method was used in this aerobiological study. Six taxa of pollen grains and fi ve types of fungal spores characterized by strong allergenicity and/or high concentrations in the air were analyzed. The time series of pollen grains and fungal spores were compared using PCA analysis. The periods of the greatest concentrations of tree pollen did not coincide with similar periods for herbaceous plants and fungal spores. From February to mid-March, Alnus pollen dominated in the air. The second period was characterized by Betula pollen. It occurred in April. Herbaceous pollen and fungal spores occurred in the air simultaneously (from mid May to the end of August), creating a risky situation for sensitized people. The periods of the highest concentrations of Epicoccum and Ganoderma fungal spores did not coincide with the same period for the examined plant taxa. In Rzeszów the probability of becoming exposed to very high concentrations of allergenic pollen and fungal spores at the same time was high, especially in July, when the highest concentrations of Poaceae, Alternaria and Cladosporium were noted. The hypersensitivity to only one plant or fungal allergen is rarely encountered. Under the present scenarios of global warming, pollen seasons of many taxa will be longer and sufferers will have year-long symptoms.

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Co-occurrence patterns of wood-decaying fungi on Picea abies logs: does Fomitopsis pinicola influence the other species?

84%

Pouska V., Svoboda M., Leps J.

Polish Journal of Ecology

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2013

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tom 61

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nr 1

Dominant fungi, especially primary decayers, probably influence other fungi growing together with them. Fomitopsis pinicola is one of the important primary decayers, and it has been shown that several other species regularly co-occur together with it. We asked whether the presence of common species (especially F. pinicola) affects the species richness and composition of other fungi. This study was conducted in an old-growth mountain spruce forest in the Bohemian Forest, Czech Republic. We surveyed logs on the ground for sporocarps of fungi in three successive years. Characteristics of logs such as dimensions, stage of decay and the cause of tree death (wind, competition, butt rot, bark beetles and unascertained) were recorded. F. pinicola was abundant mostly on logs that originated from trees infested by bark beetles. Analysis of covariance with the volume of logs and decay stage as covariables showed significant effect of these covariables and of F. pinicola presence on species numbers – logs in middle decay stages with the sporocarps of F. pinicola had more species than other logs. Based on Canonical Correspondence Analysis with volume, decay stage and the cause of tree death as covariables, the species composition on logs was also influenced by F. pinicola. We found such statistical effects in several other species. Redlisted species Antrodiella citrinella and Camarops tubulina co-occurred with F. pinicola.

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Is the community of fish gill parasites structured in a Neotropical floodplain?

67%

Bellay S., Takemoto R. M., Oliveira E. F.

Acta Parasitologica

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2012

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tom 57

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nr 1

Sixty-one specimens of the piranha Serrasalmus marginatus Valenciennes, 1837 were analyzed, aiming at assessing the community structure of their gill parasites. The samples were collected in lagoons of the Paraná, Ivinheima and Baia Subsystems within the Upper Paraná River Floodplain (Brazil). Host size and sex had little or no influence on the abundance and prevalence of parasites. The organization of the gill parasite infracommunities of S. marginatus was significantly non-random according to null models and ordination analyses. In general, parasite infrapopulations were not affected by interspecific associations or host characteristics (e.g. size, sex), what highlights the importance of local habitat characteristics to community organization of gill parasites of S. marginatus in the Upper Paraná River Floodplain.

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Aquatic snails of tributaries to the Narew River

67%

Lewin I.

Folia Malacologica

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1999

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tom 07

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nr 4

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Ecological interaction networks: prospects and pitfalls

67%

Ulrich W.

Ecological Questions

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2009

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tom 11

Interaction networks are a tool to visualize and to study the relationships between interacting species across and within trophic levels. Recent research uncovered many properties of such networks that remained undetected in previous food web studies. These patterns could be related to evolutionary and ecological processes. The study of interaction networks promises therefore progress in the study of constraints that act on the coevolution of interacting species and on food webs. However, there are still many pitfalls associated with the statistical analysis, the properties of the metrics involved and the appropriate null model choice. Here I review the mechanisms that shape interaction matrices, the possible internal structures and their ecological interpretation, and the analytical tools to identify matrix structure. Progress in the field needs critical meta-analytical and comparative studies that indentify the best suited null models (low type I and II error probabilities and high power to disentangle statistical from ecological processes) and clarify the interdependence of different concepts and metrics associated with network approaches. It is not improbable that many patterns recently associated with ecological and evolutionary processes might turn out to be simple side effects of the sampling from the underlying metacommunity distributions.

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