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Mushrooms produce a great variety of defense chemical compounds to protect themselves from fungivores. Alpha‐amanitin is one of such compounds found in some Amanita mushrooms. The present study focuses on the effect of α‐amanitin on adult survival in 17 drosophilid species including mycophagous ones from the subgenus Drosophila and the genus Hirtodrosophila and nonmycophagous ones of the subgenera Drosophila, Siphlodora and Sophophora. The results showed that all the essential fungivores and some partially mycophagous species from different lineages are tolerant to this lethal toxin at a concentration of 50 μg/mL, suggesting that the α‐amanitin tolerance may have been acquired more or less independently of the evolution of mycophagy in the family Drosophilidae. [ABSTRACT FROM AUTHOR]

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The present compendium is based on the findings of a research work on the survey of nematodes belonging to the family Aphelenchoidea in the northeastern states of India and the literature available on this particular species, mainly from Manipur. During the study, a total of 12 Aphelenchoides spp. were found, among which six species were reported for the first time from Manipur. A new species, Aphelenchoides oryzae is also described in the present article. The present study will help in making us understand the biodiversity status of Aphelenchoides nematodes in the region. Diagnosis of the species and illustrations along with dichotomous keys are provided in the manuscript. [ABSTRACT FROM AUTHOR]

Abstract We compared the response to resource enhancement of a simple empirical model of intra‐guild predation (IGP) to the predictions of published, simple mathematical models of asymmetric IGP (a generalist IG Predator that feeds both on a specialist IG Prey and a Resource that it shares with the IG Prey). The empirical model was a food‐web module created by pooling species abundances across many families in a speciose community of soil micro‐arthropods into three categories: IG Predator (large predatory mites), IG Prey (small predatory mites), and a shared Resource (fungivorous mites and springtails). By pooling abundances of species belonging to broadly defined functional groups, we tested the hypothesis that IGP is a dominant organizing principle in this community. Simple mathematical models of asymmetric IGP predict that increased input of nutrients and energy to the shared Resource will increase the equilibrium density of Resource and IG Predator, but will decrease that of IG Prey. In a field experiment, we observed how the three categories of the empirical model responded to two rates of addition of artificial detritus, which enhanced the food of fungivores, the Resource of the IGP module. By the experiment's end, fungivore densities had increased ~1.5× (ratio of pooled fungivore densities in the higher‐input treatment to plots with no addition of detritus), and densities of IG Predators had increased ~4×. Contrary to the prediction of mathematical models, IG Prey had not decreased, but instead had increased ~1.5×. We discuss possible reasons for the failure of the empirical model to agree with IGP theory. We then explore analogies between the behavior of the empirical model and another mathematical model of trophic interactions as one way to gain insights into the trophic connections in this community. We also propose one way forward for reporting comparisons of simple empirical and mathematical models.

Simple Summary: Hairy fungus beetle, Typhaea stercorea, is a secondary post-harvest pest of stored grains that thrives by feeding on mytoxigenic fungi. Bacterial communities residing in the alimentary canal of most insects contribute to their host's development. While there are many examples, little is known about the role of bacterial communities in the alimentary canal of T. stercorea. The objectives of this study were to (1) characterize the microbial communities residing in T. stercorea and (2) compare the microbial compositions of field-collected and laboratory-reared populations. In this study, we were able to identify bacterial communities that possess mycolytic properties and track mark changes in the microbiota profiles associated with development. The genus Pseudomonas was enriched in T. stercorea larvae compared to adults. Furthermore, field-collected T. sterocrea adults had a lower species richness than both larva and adult laboratory-reared T. sterocrea. Moreover, the gut microbial compositions of field-collected and laboratory-reared populations were vastly different. Overall, our results suggest that the environment and physiology can shift the microbial composition in the alimentary canal of T. stercorea. The gut microbiomes of symbiotic insects typically mediate essential functions lacking in their hosts. Here, we describe the composition of microbes residing in the alimentary canal of the hairy fungus beetle, Typhaea stercorea (L.), at various life stages. This beetle is a post-harvest pest of stored grains that feeds on fungi and serves as a vector of mycotoxigenic fungi. It has been reported that the bacterial communities found in most insects' alimentary canals contribute to nutrition, immune defenses, and protection from pathogens. Hence, bacterial symbionts may play a key role in the digestive system of T. stercorea. Using 16S rRNA amplicon sequencing, we examined the microbiota of T. stercorea. We found no difference in bacterial species richness between larvae and adults, but there were compositional differences across life stages (PERMANOVA:pseudo-F(8,2) = 8.22; p = 0.026). The three most abundant bacteria found in the alimentary canal of the larvae and adults included Pseudomonas (47.67% and 0.21%, respectively), an unspecified genus of the Enterobacteriaceae family (46.60 % and 90.97%, respectively), and Enterobacter (3.89% and 5.75%, respectively). Furthermore, Pseudomonas spp. are the predominant bacteria in the larval stage. Our data indicated that field-collected T. stercorea tended to have lower species richness than laboratory-reared beetles (Shannon: H = 5.72; p = 0.057). Furthermore, the microbial communities of laboratory-reared insects resembled one another, whereas field-collected adults exhibited variability (PERMANOVA:pseudo-F(10,3) = 4.41; p = 0.006). We provide evidence that the environment and physiology can shift the microbial composition in the alimentary canal of T. stercorea. [ABSTRACT FROM AUTHOR]

The millipede Brachycybe lecontii Wood, 1864 is a fungivorous social millipede known for paternal care of eggs and forming multi-generational aggregations. We investigated the life history, paternal care, chemical defence, feeding and social behaviour of B. lecontii and provided morphological and anatomical descriptions, using light and scanning electron microscopy. Based on observations of B. lecontii from 13 locations throughout its distribution, we report the following natural history aspects. The oviposition period of B. lecontii lasted from mid-April to late June and the incubation period lasted 3–4 weeks. Only males cared for the eggs and subsequent care of juveniles was not observed. In one case, the clutches of two males became combined and they were later cared for by only one of the males. The defensive compound of B. lecontii is stored in large glands occupying a third of the paranotal volume and were observed only in stadia II millipedes and older. We observed B. lecontii feeding on fungi of the order Polyporales and describe a cuticular structure on the tip of the labrum that may relate to fungivory. We found that their stellate-shaped aggregations (pinwheels) do not form in the absence of fungus and suggest the aggregation is associated with feeding. We describe and illustrate a previously undescribed comb-like structure on the tibia and tarsi of the six anterior-most leg-pairs and measure the colour and spectral reflectance of the B. lecontii exoskeleton.

We compared the response to resource enhancement of a simple empirical model of intra‐guild predation (IGP) to the predictions of published, simple mathematical models of asymmetric IGP (a generalist IG Predator that feeds both on a specialist IG Prey and a Resource that it shares with the IG Prey). The empirical model was a food‐web module created by pooling species abundances across many families in a speciose community of soil micro‐arthropods into three categories: IG Predator (large predatory mites), IG Prey (small predatory mites), and a shared Resource (fungivorous mites and springtails). By pooling abundances of species belonging to broadly defined functional groups, we tested the hypothesis that IGP is a dominant organizing principle in this community. Simple mathematical models of asymmetric IGP predict that increased input of nutrients and energy to the shared Resource will increase the equilibrium density of Resource and IG Predator, but will decrease that of IG Prey. In a field experiment, we observed how the three categories of the empirical model responded to two rates of addition of artificial detritus, which enhanced the food of fungivores, the Resource of the IGP module. By the experiment's end, fungivore densities had increased ~1.5× (ratio of pooled fungivore densities in the higher‐input treatment to plots with no addition of detritus), and densities of IG Predators had increased ~4×. Contrary to the prediction of mathematical models, IG Prey had not decreased, but instead had increased ~1.5×. We discuss possible reasons for the failure of the empirical model to agree with IGP theory. We then explore analogies between the behavior of the empirical model and another mathematical model of trophic interactions as one way to gain insights into the trophic connections in this community. We also propose one way forward for reporting comparisons of simple empirical and mathematical models. [ABSTRACT FROM AUTHOR]

The millipede Brachycybe lecontii Wood, 1864 is a fungivorous social millipede known for paternal care of eggs and forming multi-generational aggregations. We investigated the life history, paternal care, chemical defence, feeding and social behaviour of B. lecontii and provided morphological and anatomical descriptions, using light and scanning electron microscopy. Based on observations of B. lecontii from 13 locations throughout its distribution, we report the following natural history aspects. The oviposition period of B. lecontii lasted from mid-April to late June and the incubation period lasted 3-4 weeks. Only males cared for the eggs and subsequent care of juveniles was not observed. In one case, the clutches of two males became combined and they were later cared for by only one of the males. The defensive compound of B. lecontii is stored in large glands occupying a third of the paranotal volume and were observed only in stadia II millipedes and older. We observed B. lecontii feeding on fungi of the order Polyporales and describe a cuticular structure on the tip of the labrum that may relate to fungivory. We found that their stellateshaped aggregations (pinwheels) do not form in the absence of fungus and suggest the aggregation is associated with feeding. We describe and illustrate a previously undescribed comb-like structure on the tibia and tarsi of the six anterior-most leg-pairs and measure the colour and spectral reflectance of the B. lecontii exoskeleton. [ABSTRACT FROM AUTHOR]

A mysterious female phorid fly, known for many years to be associated with fungal sporophores ("mushrooms") is identified as Megaselia marquezi Hartop et al. 2015. Male and female flies were collected emerging from the fungus Psathyrella candolleana (Fr.) Maire, and females were observed swarming over the sporophores.

Premise: The genus Arisaema (Araceae) has rapidly diversified in Japan, and multiple species often coexist in the field. Although Japanese Arisaema species hybridize from artificial crossing, hybrid individuals are rare in mixed populations; suggesting the presence of effective pre‐pollination barriers. We examined the following reproductive barriers between A. sikokianum and A. tosaense: habitat, phenology, and pollinator isolations. Methods: Habitat isolation was examined by interspecific comparisons of microhabitat conditions at a mixed site and of altitude at the sampling site of herbarium specimens. Phenological isolation was evaluated by comparing seasonal transition in apparent spathe condition and frequency of insect visitation. Pollinator isolation was examined by comparing floral visitor assemblages between the two Arisaema species. To avoid overestimation of pollinator isolation due to seasonal changes in insect assemblages, we also compared visitor assemblages between natural and late‐flowering A. sikokianum, where the latter was experimentally introduced and blooming with a natural A. tosaense population. Results: Microhabitat conditions and sampling elevations of herbarium specimens overlapped between the two Arisaema species. At the population level, A. sikokianum and A. tosaense flowered for 39 and 52 days, respectively, with 13 days overlap. Insect visitation in A. sikokianum decreased before the seasonal overlap. Floral visitor assemblages differed between the two Arisaema species, while the difference between natural and late‐flowering A. sikokianum was less distinct. Conclusions: Phenological and pollinator isolation contribute to reproductive isolation between the two Arisaema species and should enable the two species to coexist in this area. [ABSTRACT FROM AUTHOR]

The mushroom phorid fly, Megaselia halterata (Wood) (Diptera: Phoridae), is a key pest in mushroom farming in most parts of the world. Studies on the mushroom phorid fly have focused on its life history within mushroom growing houses, but little is known about the fly's activity outside mushroom growing houses. In this study, daily activity and distribution of adult M. halterata in the areas surrounding mushroom growing houses was studied using yellow sticky traps. Results suggest that M. halterata focuses its flight activity over turf areas rather than windbreaks and spent compost piles, possibly for mating purposes. Our study found no evidence of M. halterata breeding in turf areas surrounding mushroom growing houses. In addition, flight activity is highest in the afternoon until midnight at higher temperatures, yet at lower temperatures activity ceases after sunset. Establishing temperature and daylight thresholds for M. halterata flight activity may be useful in developing integrated pest management (IPM) tactics for this species. The most successful IPM tool that mushroom growers use at present is fly exclusion. Exclusion can be improved by focusing farm operations around temperature and daylight thresholds when fly activity is at its lowest. [ABSTRACT FROM AUTHOR]

Bacteria degrading α‐(1→3)‐glucan were sought in the gut of fungivorous insects feeding on fruiting bodies of a polypore fungus Laetiporus sulphureus, which are rich in this polymer. One isolate, from Diaperis boleti, was selected in an enrichment culture in the glucan‐containing medium. The bacterium was identified as Paenibacillus sp. based on the results of the ribosomal DNA analysis. The Paenibacillus showed enzyme activity of 4.97 mU/cm3 and effectively degraded fungal α‐(1→3)‐glucan, releasing nigerooligosaccharides and a trace amount of glucose. This strain is the first reported α‐(1→3)‐glucan‐degrading microorganism in the gut microbiome of insects inhabiting fruiting bodies of polypore fungi. Bacteria degrading α‐(1→3)‐glucan were sought in the gut of fungivorous insects feeding on fruiting bodies of a polypore fungus Laetiporus sulphureus, which are rich in this polymer. One isolate identified as Paenibacillus sp. was selected from Diaperis boleti gut in an enrichment culture in the glucan‐containing medium. The Paenibacillus effectively degraded fungal α‐(1→3)‐glucan, releasing nigerooligosaccharides and a trace amount of glucose. [ABSTRACT FROM AUTHOR]

A mysterious female phorid fly, known for many years to be associated with fungal sporophores ("mushrooms") is identified as Megaselia marquezi Hartop et al. 2015. Male and female flies were collected emerging from the fungus Psathyrella candolleana (Fr.) Maire, and females were observed swarming over the sporophores. [ABSTRACT FROM AUTHOR]

[Display omitted] • MAPK signaling pathway plays a key role in the direct defenses of Pleurotus ostreatus against mite feeding and mechanical wounding. • JA signal pathways may induce various secondary metabolites to mediate direct resistance. • Sesquiterpenes may regulate the chemical defenses of P. ostreatus. Fungal chemicals are vital in processes recognizing damage- and microbe-associated molecules (DAMPs/MAMPs) that trigger defense responses in fungi. Pleurotus ostreatus is a widely cultivated edible fungus that is prone to attack from fungivorous insects and mites. Yet P. ostreatus has evolved an elegant defense system against fungivore attacks. In this study, we investigated how the oyster mushroom responds to the fungivory and mechanical wounding by conducting transcriptome, proteome, and secondary metabolic analyses. The profiling analysis revealed a total of 11,495 transcripts and 866 proteins, 4416 differentially expressed genes (DEGs), and 62 differentially expressed proteins (DEPs) were identified in response to the mite Tyrophagus putrescentiae feeding and mechanical wounding. In comparing the responses induced by mechanical wounding, some genes, proteins, and metabolites were uniquely induced or repressed by the mite. At the transcript level, nine pathways were activated by the mite feeding, including those of "MAPK signaling pathway–yeast", "Phenylalanine metabolism", and "Biotin metabolism", among others, while both enrichment of "Ribosome", "Ribosome biogenesis in eukaryotes", and "Regulation of Mitophagy in Yeast" demonstrated the common effects upon fungal secretory protein synthesis and processing induced by fungivory and mechanical wounding. Fungivory also stimulated the synthesis of C 8 -aryl compounds and sesquiterpenes (especially1-octen-3-ol and α-/β-bisabolene), and these compounds repellent to T. putrescentiae. Both jasmonic acid (JA) and jasmonic acid methyl ester (MeJA) were specifically regulated by mite feeding and mechanical wounding. The terpene synthase gene transcription was significantly increased induced by the exogenous addition of MeJA, resulting in defensive sesquiterpene production against the mite. These findings are the first to demonstrate that the reactive oxygen species (ROS)/MAPK signaling pathway, JA regulation, specific gene expression, and protein synthesis, and anti-mite substance metabolism are all involved in coordinated inducible chemical-based defense responses in P. ostreatus , which could be especially effective the mite T. putrescentiae. [ABSTRACT FROM AUTHOR]

Empirical impact evidence exists for few of New Zealand's environmental weeds. Financial constraints prevent managers examining all impacts of all weeds. Therefore it is useful to seek generalisable rules which allow managers to predict impacts of new invasions. Invasive weeds may indirectly affect fungivorous invertebrates through mechanisms such as altered litter-fall, decomposition rates, and microclimate, all of which may alter fungal activity. I tested the hypothesis that fungivorous invertebrates would be consistently affected by three invasive weeds, and that this effect would be more pronounced than for other invertebrate functional groups. Using pitfall traps, I compared invertebrates beneath climbing asparagus, tradescantia and ginger with invertebrates of uninvaded lowland forest. Five out of six Coleoptera taxa which differed in abundance between invaded and uninvaded sites were fungivores; the remaining taxon was a saprophage. At least two taxa of fungivorous Coleoptera responded to each of the three weed species. Acari (mainly Oribatids, some of which are fungivores), Isopoda and Amphipoda (decomposers) were the only taxa to respond to the presence of all three weed species. These results provide some support for the hypothesis that fungivores are particularly responsive to ground-cover weed invasion, but suggest this could be extended to include decomposers as well. However, the direction of effect differed among weed species. Therefore, while changes in fungivore and decomposer abundance may be predicted as one of the more likely consequences of ground-cover weed invasion in New Zealand low-land forest, site- and taxa-specific effects make it difficult to predict the direction of effect. [ABSTRACT FROM AUTHOR]

Invasive Alternanthera philoxeroides (alligator weed), when controlled by biocontrol agent Agasicles hygrophila, is known to differ from native vegetation in its decomposition dynamics. This study investigated whether this difference would have indirect effects for fungal-feeding Coleoptera. The study tested the hypothesis that fungivores would be more abundant and species rich on A. philoxeroides than on native vegetation. The study also tested the hypothesis that fungivores would be more affected than other functional groups. The study was conducted in a northern New Zealand lake. Litterbags were placed beneath A. philoxeroides and two native sedge species ( Schoenoplectus tabernaemontani and Isolepis prolifer). Coleoptera communities were examined from the litterbags. Fungivorous Coleoptera were more abundant and species rich beneath A. philoxeroides than beneath either sedge species. No other functional groups differed between cover types. Fungivorous Coleoptera also comprised a greater proportion of total Coleoptera catch from litterbags beneath A. philoxeroides cover than from beneath native sedge cover. Four of the six fungivorous Coleoptera species collected in the study were present beneath A. philoxeroides cover. Of these, the two most abundant species (on native, one exotic) were both from the family Corylophidae. Alternanthera philoxeroides invasion is thus associated with altered Coleoptera communities in this ecosystem. [ABSTRACT FROM AUTHOR]

Abstract: The feeding habits of soil mesofauna have been a mystery for decades, and depending on the methods used, different degrees of feeding specialisation have been observed. A new way to study the almost unknown feeding habits of soil mesofauna e.g. oribatid mites is to use PCR-based techniques. When applying PCR on these small organisms, the low amount of ingested DNA can cause problems. Even more important is to certify that the amplified DNA does not originate from body-surface contamination. The aim of this study was to analyse if washing of the body surface combined with PCR can be a successful approach when identifying the food ingested by fungivorous mites. The method was developed in a laboratory system where we used the oribatid mite Archegozetes longisetosus as a model organism due to its relatively short life cycle and ease of laboratory culturing. The results demonstrated that surface contamination is a serious problem. Both washing and dissection was needed to remove surface contamination on such small organisms. To get a reliable result the samples also had to contain at least five pooled guts, but preferably ten. This is the first step towards a successful use of PCR-based methods to study natural feeding habits of species most likely contaminated on the body surface. When modified for field conditions, the results obtained by this method have a high potential to answer many questions about the animals feeding habits, and their functional role in the soil. [ABSTRACT FROM AUTHOR]

Abstract: The oribatid mites Oppiella nova, Tectocepheus velatus and Nothrus silvestris and the enchytraeid worm Cognettia sphagnetorum are four common animal species in boreal forest soils. According to the literature, they respond differently to clear-cutting of forest stands. O. nova responds with population decreases, T. velatus and N. silvestris with small changes and C. sphagnetorum with population increases. We hypothesised that the presence/absence of ectomycorrhizal (EM) fungi is a major factor in explaining these reactions. The population responses of these soil animals to inoculation of five species of EM fungi growing in symbiosis with their host tree (Pinus sylvestris L.) and one saprotrophic fungus, Hypholoma capnoides, growing on wood were tested in pot microcosms with artificial soil (peat and vermiculite) for 70–84 days. Additionally, plants without inoculation of EM fungi, plants growing in forest soil (FS) and plant-free peat and vermiculite (PV) were included. O. nova increased significantly in abundance in the treatments with the EM fungi Suillus variegatus and Paxillus involutus, but not in the other treatments. T. velatus increased significantly in abundance in FS, but declined in most of the other treatments, and N. silvestris showed a similar, albeit not significant, response. C. sphagnetorum did not increase in abundance in any of the treatments with EM fungi but increased its abundance four times in both FS and PV. The results show that the fungivore O. nova preferentially feeds on certain EM fungi, especially S. variegatus, whereas the EM fungus Piloderma fallax and the saprotrophic H. capnoides are not preferred. In contrast, C. sphagnetorum is restricted in its population growth by the EM fungi studied, and this dominant microbi-detritivore is clearly favoured by the absence of EM fungi. [Copyright &y& Elsevier]

Since its accidental introduction to southeast England during the nineteenth century, the invasive Australasian fungivore, Cis bilamellatus, has spread across England, Wales and Southern Scotland. Recently it has been recorded from Ireland, the Channel Islands and north-west France. On mainland Britain, an establishment phase spanning an estimated maximum of 45 years was followed by biphasic range expansion comprising a slow start of 1.6 km year-1 between 1910 and 1930, followed by 40 years of approximately linear spread of 13 km year-1. Northwards expansion now appears to be limited by sub-zero winter temperatures and is no longer apparent. Comparison with historic records of native ciids shows that this range expansion is genuine, rather than an artefact of recording effort or bias. It has no doubt been facilitated by C. bilamellatus' ability to exploit a wide range of sometimes under-used fungal resources, by its favourable rate of increase, by its tolerance of both wet and dry conditions, and by a low rate of parasitoid attack. Although there is the potential for direct and indirect interaction between C. bilamellatus, native ciids and their shared parasitoids, the current ecological impact of C. bilamellatus appears to be low. It seems likely that C. bilamellatus will spread through Europe, limited primarily by resource availability and low winter temperatures. [ABSTRACT FROM AUTHOR]

Contents This review analyses the phenomenon of bacterial mycophagy, which we define as a set of phenotypic behaviours that enable bacteria to obtain nutrients from living fungi and thus allow the conversion of fungal into bacterial biomass. We recognize three types of bacterial strategies to derive nutrition from fungi: necrotrophy, extracellular biotrophy and endocellular biotrophy. Each is characterized by a set of uniquely sequential and differently overlapping interactions with the fungal target. We offer a detailed analysis of the nature of these interactions, as well as a comprehensive overview of methodologies for assessing and quantifying their individual contributions to the mycophagy phenotype. Furthermore, we discuss future prospects for the study and exploitation of bacterial mycophagy, including the need for appropriate tools to detect bacterial mycophagy in situ in order to be able to understand, predict and possibly manipulate the way in which mycophagous bacteria affect fungal activity, turnover, and community structure in soils and other ecosystems. [ABSTRACT FROM AUTHOR]

Summary: The Lacandon Maya of Chiapas, Mexico practice a system of agroforestry that mimics the surrounding ecosystem and its successional stages. Their fields rotate through grass (milpa), and shrub (acahual) and forest fallow stages that regenerate soil, nutrients, and seed banks. Each successional stage, including the fallow stages, produces over 25 types of crops, raw materials, and medicines. Lacandon traditionally do not use fertilizers, pesticides, or herbicides. Nematodes were chosen to analyze soil ecology in the Lacandon system because they have been shown to be dynamic indicators of environmental conditions. Nematodes were classified by trophic level as plant parasite, fungivore, bacterivore, and omnivore-predator, and were found to be a function of management practice. In milpas where weeds were removed and applied to the field, plant parasites were reduced by 44% and fungivorous nematode concentrations were reduced by 50%. In these same fields, percentage of bacterivorous nematodes was positively related to soil organic matter concentration (, ). These results indicate that management practices reduced concentrations of plant parasites and delayed the nematode successional pathway from bacterivorous to fungivorous. This study demonstrates the potential for Lacandon Maya techniques to sustainably manage pests and maintain soil fertility in other tropical agroecosystems. [Copyright &y& Elsevier]

The compensatory growth potential of a grazed fungal biomass was mathematically expressed as a function of patchiness in its distribution and demonstrated in an experiment using the fungivorous collembolan Onychiurus armatus and the soil fungi Verticillium bulbillosum and Penicillium spinulosum. The model addresses the regrowth potential in relation to patch fragmentation, travelling time and consumption rate of the collembolan and the mean relative growth rate of the fungus. It suggests that the mean relative growth rate required for regrowth decreases with patch fragmentation and increases with the mean growth rate of the fungus. The experiments were performed with a system of soil-filled vials provided with fungi and collembolans. The size of the vials and the length of the tubes connecting them were varied to give different patch sizes and travelling times. The respiratory activity of fungi after grazing increased as a unit of mycelium was distributed into smaller connected vials. The slow growing species V. bulbillosum showed a greater but delayed response to grazing in comparison with the fast growing P. spinulosum. An increased travelling time delayed the growth response in both species. [ABSTRACT FROM AUTHOR]

The mite and fungal biota associated with the mountain pine beetle (MPB) (Dendroctonus ponderosae Hopk.) may not be stable throughout an irruptive event. In congeneric beetles, variations in the frequency of their associated organisms affect population trends and similar effects may occur in MPB. We studied fungi and mite trends in a declining irruptive MPB population as it attacked three different pine hosts in the Colorado Front Range. During the study, we found two new associates including one biologically relevant mite and one beneficial blue-stain fungus. Fungi hyperphoretic on mites were also documented. This included beneficial and potentially detrimental species to the MPB. The frequency of several organisms varied between some years or pine hosts but not within male or female beetles. A large increase of Trichouropoda sp. and T. ips mites trended inversely with the declining beetle population, while a decrease in the beneficial blue-stain fungi trended similarly to the declining beetle population. We discuss the interactions and potential effects of phoretic biota in relation to (1) the MPB associates’ population trends, (2) the MPB incursions into cooler areas, and (3) the redundancy of blue-stain fungi carried by the MPB holobiont. These findings increase our knowledge of the mechanisms that influence MPB populations. [ABSTRACT FROM AUTHOR]

The effect of tillage intensity on nematode community trophic structure and the role of nematodes in the regulation of decomposition rates in agroecosystems were examined. Conventional (CT) and no-tillage (NT) agroecosystems were sampled monthly for 1 year. Tillage affected nematode trophic structure and total abundance. Monthly mean densities of bacterivorous, fungivorous, and total nematodes were greater in CT than in NT plots. In the summer, however, fungivorous and plant parasitic nematodes were more abundant in NT. No difference was detected for omnivore-predator nematodes.