Fungal Ecology最新文献

Aerial photos and Google Earth images of the Laramie Basin in Wyoming were used to measure size, and calculate species-specific growth rates and ages for 304 rings comprising eight species of fairy ring forming fungi. Estimated age was used to explore establishment, dynamics and persistence in relation to historic precipitation and drought data. Size of fairy rings ranged from 4 to 272 meters, and age from 15 to 522 years. 90% of all rings were younger than 80 years. Species-specific growth rates varied from 0.131 to 0.364 meters per year. All fairy ring species became established over a wide range of precipitation, although most rings established during years with 25–30 centimeters of precipitation. Little correlation was observed between establishment and precipitation patterns for some fungi, however others exhibited a significant relationship between year of establishment and both August precipitation and the Palmer Modified Drought Index. Expansion of one large ring was followed for 75 years. These data demonstrate that turnover in fairy rings is quite high and that fairy ring fungi can establish over a wide range of moisture levels.

We investigated the wood fungal community composition in stems of living Norway spruce (Picea abies (L.) Karst.) trees in 20–40 year-old forest stands from Latvia that differed in recent management history (stands with or without thinning) and former land use (former agricultural or former forest lands). Fungal internal transcribed spacer (ITS2) amplicons of DNA extracted from wood were sequenced to assess wood fungal communities. Alternaria, Ascocoryne, Didymella, Heterobasidion, Ophiostoma, Orbilia, Pesotum, Phoma and Pseudocercosporella were the dominant wood pathogen and wood saprotroph genera in the analysed samples. PERMANOVA analysis identified some differences in fungal communities among site types analysed (p < 0.001); tree height and presence/absence of rot in the wood samples (mainly Heterobasidion rot) significantly influenced fungal community composition (p < 0.001). Significant negative co-occurrence (p < 0.05) was observed between Heterobasidion and Ascocoryne genera indicating the differing wood colonizing niches of these taxa. Both stand level factors, such as management history and former land use, and tree level parameters are significant for wood inhabiting fungal communities of living spruces.

Forests can experience negative feedbacks in the growth of tree populations but positive feedbacks within the two dominant mycorrhizal types of trees: ectomycorrhizal (EM) and arbuscular mycorrhizal (AM). Positive feedbacks within mycorrhizal types may provide communities with resistance to climate change. We tested whether each mycorrhizal type led to positive feedbacks on seedling survival, while statistically controlling for the effect of congeneric trees in ambient versus rainfall reduced conditions. We explored two potential drivers: the variation in soil fungal community structure and soil chemistry. Seedlings benefited from growing in stands dominated by their own mycorrhizal type, and simultaneously, tree seedlings performed worse in the presence of adult trees of their own genus, but only in rainfall reduced conditions. We found that the composition of the EM fungal community differed between plots dominated by EM versus AM trees. These results indicated that mycorrhizal types may create positive feedbacks in dry conditions that should be considered when predicting future states.

The generalist entomophthoralean insect pathogen Batkoa major was recorded causing epizootics in populations of a new invasive fulgorid in North America, the spotted lanternfly (Lycorma delicatula). We conducted studies on the basic biology and ecology of B. major using Galleria mellonella larvae exposed to conidial showers. Death of G. mellonella followed a diurnal cycle with most larvae dying within 4 h before or after the end of photophase. Time for initiation of rhizoid emergence also followed a diurnal rhythm and, on average occurred 3.6 h after host death. While B. major sometimes began producing rhizoids to attach cadavers to substrates while G. mellonella were alive (but moribund), often hosts were dead before rhizoids began emerging. On average, conidial discharge began 18.6 h after host death and was greater 4–8 h before the end of photophase, compared with 4–8 h after scotophase began. At 20 °C under high humidity, initiation of conidial discharge was 95% complete within 24 h after host death. To evaluate B. major activity by temperature, we tested percent conidial germination over 24 h from 5 to 35 °C. When showered onto water agar, all primary conidia produced secondary conidia. At 20 and 25 °C, at 3 h ≥89% of primaries had produced and discharged secondaries and from 10 to 30 °C, secondaries were produced by over 75% of primary conidia within 12 h. When cover slips were placed over primary conidia to force production of germ tubes, germination was much slower, with >85% germination from 20 to 30 °C only by 24 h. Batkoa major therefore times host death and initiation of conidial discharge for night-time hours and conidial germination occurs within 24 h over a broad temperature range (10–30 °C).

There is substantial fungal diversity in marine environments where uncharacterized species may play important ecological roles. Malassezia, a genus of yeast generally associated with mammalian skins, is an example of a seemingly abundant marine fungus in ocean environments. Accumulating evidence indicates that Malassezia is widespread in the ocean. However, we know little about its diversity, role, and distribution. To address these gaps in our knowledge, we analyzed 127 marine samples collected from marine rocks, sediment, water, and various organisms, from the coasts of Hawaiʻi, Washington, and Massachusetts. We then used Malassezia-specific 28S primers in a nested PCR approach to amplify all present Malassezia, and performed Illumina sequencing from which we generated a possible phylogeny. Based on our phylogenetic results, we circumscribed 20 potentially novel clades that might represent new species. Our findings are consistent with Malassezia having substantial novel diversity and a high prevalence in the marine environment.

Host identity and location help shape fungal endophyte assemblages in plants. Hosts act as uptake filters from the environment and closely related hosts in the same location may harbour similar assemblages. We assessed the influence of host identity and geographic location on endophytic fungal assemblages within the native African olive and cultivated European olive in South Africa using high throughput sequencing. As hypothesised, the two hosts were found to share many endophytic species, but alpha diversity was lower within the European olive. The two hosts had significantly dissimilar endophyte assemblages. Distance between sites positively correlated with endophyte assemblage dissimilarities, demonstrating a strong effect of the surrounding environment on endophyte assemblages. African olive individuals had highly connected endophyte assemblages, unlike those within the European olive. Microbiome sharing and disconnected assemblages may have negative impacts on the health of the cultivated host.

Sarcosoma globosum is a spring-fruiting ascomycete associated with boreal spruce forests characterized by long forest continuity. It is assessed as Near Threatened (NT) according to the global evaluation of International Union for Conservation of Nature (IUCN). We report data of S. globosum in Finland for 1915–2021, before and after availability of digital observation tools (<2015 vs. 2015>). Here, we report in total 586 observations of S. globosum in Finland. We report a huge increase of S. globosum observations since 2015 (+786% average annual increase in observations compared to years 1990–2014). Specimens deposited in public herbaria and data from the environmental authorities have declined. Our results indicate emergence of a new, citizen-based observation culture of fungi. Changes in observation activity may disguise true changes in fungal populations.

Phyllosphere fungi form close ecological ties with their hosts and participate in multiple ecosystem processes. This research investigated simulated climate change effects of warming and precipitation manipulationon the Aster tataricus fungal community in a Qinghai-Tibetan Plateau alpine meadow. Increased precipitation increased the fungal community diversity and richness indices, but warming had the opposite effect. Warming and precipitation adjustment in combination reduced the fungal community diversity. FUNGuild functional analysis of differences in the leaf fungal community in our study, and linked statistical analysis, determined that increasing precipitation significantly reduced relative abundance of pathogenic fungi and incidence of plant diseases, while warming and decreased precipitation did the opposite. Differences in the leaf fungal community in our study under warming and decreased precipitation would be predicted to increase incidence of plant diseases. These climate change simulations improve awareness of future plant disease risks in natural plant communities and provide opportunities to develop responses.

The functional diversity of fungi remains poorly explored in the deep-sea, particularly in hydrothermal vents. Here, we approached this gap through the analysis of stable isotopes of carbon (δ¹³C), nitrogen (δ¹⁵N), and sulfur (δ³⁴S) of fourteen isolates obtained from three deep-sea vent systems of the southern Gulf of California. The δ¹³C results indicated that 60% of the isolates relied on mixed carbon sources fixed by the Calvin-Benson-Bassham and the reductive Tricarboxylic Acid (rTCA) cycles, whereas 40% relied exclusively on rTCA carbon. The δ¹⁵N and δ³⁴S values suggested a dependence on local and external nitrogen sources and the assimilation of chemosynthetic and photosynthetic inputs. Fungal δ¹³C and δ¹⁵N overlapped with those of primary and secondary vent macroconsumers, implying the assimilation of bacterial and invertebrate necromass and their ecological role as parasites. These findings provide insights into the unexplored trophic versatility of fungi in chemosynthetic ecosystems, highlighting their importance in deep-sea trophic dynamics.

Patterns and drivers of succession provide insight into the mechanisms that govern community assembly, but remain poorly understood for microbial communities. We assess whether successional trends of trees are mirrored by foliar endophyte communities of three tree species across a deterministic woody successional gradient. Additionally, we test the relative contribution of abiotic predictors, biotic factors, and spatial distance between sites in predicting composition and richness of endophyte communities. Unlike the tree community, endophyte communities showed no consistent evidence of deterministic succession. Host identity was the most important factor structuring endophyte community composition; within hosts, spatial distance from the indigenous forest and between samples was important, while environmental predictors had small and inconsistent effects. Much variation in endophyte composition remained unexplained. In contrast, endophyte richness was well-explained by predictor variables. Host identity was most important in predicting endophyte richness, while the effect of other predictors on richness differed between host species. We conclude that deterministic succession in trees did not result in deterministic succession in endophyte communities; instead community assembly was most strongly influenced by host identity; while within hosts, neutral processes may be more important for endophyte assembly than deterministic factors.