Bulbs mycoflora and their relation with three stored product mites

Change in abundance of three phytophagous mite species (Acari: Eriophyidae, Tetranychidae) on quackgrass in the presence of choke disease

Phytophagous mites and endophytic fungi may interact when sharing a host plant, potentially influencing one another's growth or population dynamics; however, interactions between them are poorly known and remain largely unexplored. In this study, quantitative associations between three species of phytophagous mites and the endophytic fungus Epichloë bromicola Leuchtm. & Schardl (Clavicipitaceae, Ascomycotina) on quackgrass, Elymus repens (L.) Gould are reported. The mites' abundance was assessed on field-collected grass shoots that were either exhibiting choke disease symptoms or without the fungus. Overall, the abundance of Tetranychus urticae and Aculodes mckenziei was significantly lower on quackgrass plants infected by E. bromicola compared to plants without the fungus. Conversely, populations of Abacarus hystrix were significantly larger on plants colonised by the fungus than on uninfected plants. Thus, the presence of this endophytic fungus may have divergent effects on different phytophagous mite species although the basis of these effects is not yet known.

The effect of Tyrophagus putrescentiae on Fusarium poae transmission and fungal community in stored barley in a laboratory experiment

The effect of Tyrophagus putrescentiae on Fusarium poae transmission and fungal community composition was studied in nonsterile barley grain. The experiments included following treatments: control barley without mites; barley containing 10 or 50 mites without preincubation on F. poae (Tp10 and Tp50); barley containing 10 or 50 mites after preincubation on F. poae (FTp10 and FTp50). The number of mites, successful transfer of F. poae, and changes in the fungal communities were examined after 21 d of experiment. Increase of deoxynivalenol (DON) content in the barley was chosen as a criterion of successful F. poae transfer. The preincubation of T. putrescentiae on F. poae increased DON level approximately to 800 and 300 μg/kg of grain for FTp10 and FTp50, respectively. T. putrescentiae population growth in FTp10 was lower than in Tp10, while no difference was found between FTp50 and Tp50. Fungal communities were compared by amplification, cloning and sequencing of ITS fragments, and operational taxonomic units (OTU) analysis. The OTU analysis did not support the transfer of F. poae via mites. From the analyzed clones, only 13 cloned sequences clustered with F. poae in an OTU defined at distance level 0.07. The related clones originated from FTp10, Tp10, Tp50 and control treatments, but not from FTp50. However, the presence of F. poae in FTp50 was confirmed by PCR amplification with specific primers. The observation may be explained by different effect of mite population density, that is, in the high density, (FTp50 treatment) the fungus was overgrazed, while the lower population density (FTp10) supported F. poae transfer.

The role of mites in insect-fungus associations

The interactions among insects, mites, and fungi are diverse and complex but poorly understood in most cases. Associations among insects, mites, and fungi span an almost incomprehensible array of ecological interactions and evolutionary histories. Insects and mites often share habitats and resources and thus interact within communities. Many mites and insects rely on fungi for nutrients, and fungi benefit from them with regard to spore dispersal, habitat provision, or nutrient resources. Mites have important impacts on community dynamics, ecosystem processes, and biodiversity within many insect-fungus systems. Given that mites are understudied but highly abundant, they likely have bigger, more important, and more widespread impacts on communities than previously recognized. We describe mutualistic and antagonistic effects of mites on insect-fungus associations, explore the processes that underpin ecological and evolutionary patterns of these multipartite communities, review well-researched examples of the effects of mites on insect-fungus associations, and discuss approaches for studying mites within insect-fungus communities.

The history, fungal biodiversity, conservation, and future perspectives for mycology in Egypt

Records of Egyptian fungi, including lichenized fungi, are scattered through a wide array of journals, books, and dissertations, but preliminary annotated checklists and compilations are not all readily available. This review documents the known available sources and compiles data for more than 197 years of Egyptian mycology. Species richness is analysed numerically with respect to the systematic position and ecology. Values of relative species richness of different systematic and ecological groups in Egypt compared to values of the same groups worldwide, show that our knowledge of Egyptian fungi is fragmentary, especially for certain systematic and ecological groups such as Agaricales, Glomeromycota, and lichenized, nematode-trapping, entomopathogenic, marine, aquatic and coprophilous fungi, and also yeasts. Certain groups have never been studied in Egypt, such as Trichomycetes and black yeasts. By screening available sources of information, it was possible to delineate 2281 taxa belonging to 755 genera of fungi, including 57 myxomycete species as known from Egypt. Only 105 taxa new to science have been described from Egypt, one belonging to Chytridiomycota, 47 to Ascomycota, 55 to anamorphic fungi and one to Basidiomycota.

The role of eriophyoids in fungal pathogen epidemiology, mere association or true interaction?

A considerable number of plant feeding mites representing different families such as Acaridae, Siteroptidae, Tydeidae, and Tarsonemidae interact with plant pathogenic fungi. While species within the Eriophyoidea appear to be the most common phytophagous mites vectoring virus diseases, little is known of their role in fungal pathogen epidemiology. In the present article, we present two studies on eriophyoid-fungal relationships. The first focusing on the association between Aceria mangiferae and the fungal pathogen Fusarium mangiferae in mango is presented as a case study. The second, as the research is still in a preliminary phase, reports on quantitative and descriptive associations between the cereal rust mite Abacarus hystrix and rusts caused by Puccinia spp. Mango bud tissue colonized with F. mangiferae, and wheat and quackgrass leaves colonized with Puccinia spp., supported significantly higher populations of eriophyoid mites. Both mite species were observed bearing the spores of the respective pathogens on their body integument. Aceria mangiferae vectored the pathogen's spores into the bud, the sole port of entry for the fungal pathogen and the frequency and severity of fungal infection increased in the presence of A. mangiferae. While it appears that eriophyoids are playing a role in fungal epidemiology, clearly further research is needed to enhance our understanding of direct and indirect (plant mediated) interactions between plant pathogens and eriophyoid mites in different plant-pathogen systems.