Abstract

Onygenales is a medically important order of fungi because it houses various fungal pathogens of humans and animals. Within recent years, emerging infectious diseases perpetuated by fungal pathogens have increased in wildlife, many resulting in currently uncontrolled epidemics such as chytridiomycosis among amphibians and white nose syndrome seen among bats. Ophidiomyces ophiodiicola is the primary agent of an infectious disease affecting various species of snakes across midwestern and eastern states. The pathogen colonizes the skin of its host, causing skin lesions, facial swelling, and hardened scales that, depending on the species of snake, can be fatal. There is a large variation in species susceptibility and aspects surrounding the fungus remain unclear; primarily its diversity. The objective of my experiment is to implement high throughput sequencing to understand pathogen diversity among its geographical distribution from cultured samples obtained from the National Wildlife Health Center in Madison, Wisconsin. Targeting and amplifying the internal transcriber spacer (ITS) region, which is universal among fungi, and BLASTing the collected sequences across databases such as the National Center for Biotechnology Information and GenBank will help compare and confirm all documented strains. Understanding diversity and distribution are integral in grasping mechanisms of infectious diseases. Using high throughput sequence analysis will aid in making connections behind fungal ecology and diversity among a relatively new pathogen that is threatening species such as the Eastern Massasauga Rattlesnake and Timber Rattlesnake. Furthermore, while extensive surveying has driven higher awareness, there is a lack of vigilance along western states. Extending this method of analysis to acquired swab samples from western facilities such as the Oregon Department of Fisheries and Wildlife and from universities with invested interests in this disease such as UC Davis, a more thorough and complete geographical distribution can be built. In conclusion, diversity and ecology are two sides of the same coin when attempting to understand infectious diseases of which not only elucidates climate tolerance but also the extent of diversity.

Abstract

We aim to introduce a new cultivar of Grifola frondosa by crossing of mono-spore. The name of this cultivar is ‘Daebak’, it means jackpot. As in the case of control cultivar ‘Cham’, temperature of mycelial growth and fruiting of the ‘Daebak’ were also same at 25℃ and 18℃, respectively. The incubation period was 57days, two days shorter than that of the ‘Cham’ by bottle cultivation. The rate of fruiting for the ‘Daebak’ was 98.4%, which was 24.8%p higher than that of the 'Cham'. In addition, the coefficient of variation for the ‘Daebak’ was 0.6, which was lower than the ‘Cham’ 5.3, resulting uniform fruiting. The L-value of pileus for the ‘Daebak’ was lower than that of the ‘Cham’. The diameter of pileus and length of stem for the ‘Daebak’ were larger and higher than those of the ‘Cham’, respectively. Physical properties (strength, springness, and brittleness) of this cultivar were lower than those of the 'Cham'. The fresh weight of this cultivar was 139g/1,100㎖ and was 28% higher than that of the ‘Cham’. Additionally the new cultivar has greater uniformity due to the coefficient of variation in the quantity being lower than the ‘Cham’. Shelf life of this cultivar at 4 ℃ was 42 days and 6 days longer than that of the 'Cham'. In conclusion, new cultivar ‘Daebak’ of Grifola frondosa was in quantity, quality and storage compared to the previous cultivar ‘Cham’, but also need to be bred with a more physically strong cultivar for the future.

Abstract

The holobiont concept and hologenome theory highlight the influence that microbial communities can have on the ecology and evolution of their associated macro-organismal hosts. The outcome of those associations thereby not only depends on interactions between the microbiome and the host, but also on the interactions between members of the microbiome, including mainly bacteria and fungi, but also viruses, nematodes and protozoa. Fungi form an important part of the plant-associated microbiomes and the composition of fungal communities and the resulting interactions are highly relevant for the ecology of plants, affecting them in beneficial and/or harmful ways. Therefore, processes within natural ecosystems (e.g., nutrient cycling), as well as in agricultural systems (e.g., plant health) are strongly influenced by the mycobiome. Apple (Malus domestica Borkh) is one of the most widely cultivated fruit crops in temperate regions and in Germany by far the most important fruit tree. A better knowledge about the apple tree associated mycobiome and its functioning could enable a targeted application, resulting in better crop yields or reduction of fungicide usage. In this study, fungal communities associated to apple trees in Germany were assessed by high-throughput sequencing of amplicon barcodes. To characterize the fungal diversity associated with apple trees and the factors controlling the community assembly, we sampled 85 apple trees at seventeen locations along two transects (North-South and West-East) throughout Germany. Sampling locations were consistently selected for lack of pesticides, herbicides and fungicides. From each host, leaves, twigs and surrounding soil were collected. DNA was extracted from three independent replicates, the fungal barcode ITS1 amplified and sequenced by Illumina MiSeq. We obtained 11,311,311 quality filtered ITS1 sequences for leaf and twig samples, which were clustered into 575 OTUs. Our results revealed that the host organ and location were major factors shaping the detected fungal communities, while the distance between locations did not show a major effect. Leaf samples were more equally dominated by Ascomycetes and Basidiomycetes, while Ascomycetes prevailed by far in twig samples. A slight similarity decay along the North-South transect was also observed. We will provide insights into community assembly and further details on the fungal communities, their structure, the taxonomic distribution according to organ and geographical location.

Abstract

Rambutan (Nephelium lappaceum L.) is a tropical fruit tree that has been cultivated since 1998 on commercial orchards in Mayaguez, Puerto Rico. From 2003 to 2015, during a disease survey, leaf blight and necrotic spots were observed at commercial and experimental orchards throughout the island. Diseased leaves were disinfected and plated onto potato dextrose agar (PDA). Four isolates, A1 and A2, of Botryosphaeria spp. and A3 and A4, of Phomopsis spp. were purified and identified using taxonomic keys and DNA GeneBank sequence comparison. PCR amplifications of the ITS1-5.8S-ITS2 region and partial sequence of elongation factor 1-alpha (EF1-α) genes were used to support the identification. PCR products were sequenced and compared using BLASTn with other sequences of Botryosphaeria spp. and Phomopsis spp. submitted to the NCBI GenBank. Pathogenicity test was conducted on eight Rambutan trees, using three healthy non-detached leaves per isolate. Trees were inoculated with two separate or combined isolates for each leaf with 5mm mycelial disks from pure cultures grown on PDA. Leaves were kept in a humid chamber using plastic bags for 8 days under greenhouse conditions. Two of eight trees were untreated, inoculated with PDA disks only, and were used as controls. The test was repeated twice. Eight and 14 days after inoculations (DAI) isolates of Botryosphaeria spp. caused leaf blotch and leaf blight, respectively. For all isolates, diseased leaves turned from light brown to dark brown starting from the apex and spreading through the lamina with necrotic tissues ranging from 10mm to 40mm in leaf length. Only one isolate of Phomopsis spp. caused necrotic spots on the leaves of 5mm in diameter. To prove the pathogenicity test, Botryosphaeria spp. and Phomopsis spp. were re-isolated from diseased leaf, fulfilling Koch's postulates. Untreated controls showed no symptoms and no fungi were re-isolated from tissue. By having identified the fungal pathogens involved in leaf blight, a more specific management approach can be implemented against Rambutan tree diseases in Puerto Rico.

Abstract

A survey of collections of Siphula-like lichens [Siphula (Icmadophilaceae) and Parasiphula (Coccotremataceae)] in the herbaria of H, HO, TNS and UPS revealed a rich and highly specialised lichenicolous biota of c. 20 taxa. Of these, we have been able to identify c.10 to species rank, including five that we describe as new to science in the genera Cercidospora, Endococcus and Pyrenidium. In addition, we significantly expand the geographical distribution and the number of host species for siphulicolous fungi. By far the greatest species richness is found in the Southern Hemisphere, the centre of speciation of the host genera. The only lichenicolous species recorded from the Northern Hemisphere is Sphaerellothecium siphulae. No lichenicolous fungi are shared between Siphula sensus stricto and the morphologically similar genus, Parasiphula, providing further support for their separation.

Abstract

Hygrophoraceae, a large, attractive and divers family in Basidiomycetes, includes mainly the agaricoid white-spored mushrooms with waxy pileus and gills, some basidiolichens and some corticioid fungi. Some important morphological characters of its members are often very susceptible to environments, so it is challenging to do morphological recognition, especially for the Chinese taxa since the knowledge of Chinese Hygrophoraceae is still very limited and there is no monograph about them. Therefore, it is significant to do a systematic study based on Chinese materials. In the past seven years, with over 200 Hygrophoraceae fresh samples collected from China, three gene fragments (ITS, LSU, RPB2) were used to reconstruct the phylogenetic relationships of the family Hygrophoraceae based on both newly generated and downloaded sequences. In the results, phylogenetic framework of worldwide Hygrophoraceae shows it as a monophyly family with three monophyly subfamilies, conforming to the subfamily concepts of the previous studies without Chinese data. Under subfam. Hygrophoroideae, genera Hygrophorus and Haasiella are strongly supported as sister groups, while Chrysomphalina is the basal group. The division of subfam. Hygrocyboideae into three tribes is accepted: tribe Hygrocybeae is made by the largest genus Hygrocybe and the rough-spored genus Hygroaster; under tribe Humidicuteae, Humidicutis and Gliophorus are confirmed as sister groups with high support value, Porpolomopsis is close to them, while Neohygrocybe is located at the base of the tribe; and tribe Chromosereae is a basal group of the subfamily, including two sister genera Chromosera and Gloioxanthomyces and a new genus from China. Multigene phylogenetic analysis shows that China is rich in Hygrophoraceae resources: 13 known genera and a new genus are present, over 60 species can be recognized and at least 30 of which are new to science. Although the recognized taxa can constitute the basic categories of a monograph, more samples and sequences are still needed in order to make a more comprehensive monographic study on Chinese Hygrophoraceae. This study was financed by the National Natural Science Foundation of China (Nos. 31170026, 31370071, 31493011).

Abstract

Poplars (Populus ssp.) are an economically important wood and bioenergy crop that are nutritionally supported by both arbuscular mycorrhizal and ectomycorrhizal fungi. While aspens (P. tremula and P. tremuloides) are known to host a diverse array of ectomycorrhizal fungi, cottonwoods (P. trichocarpa, P. deltoides, and P. nigra) are considered to have a more restricted set of ectomycorrhizal associates. Here we provide a comparative overview of the reported ectomycorrhizal associates of cottonwoods informed by metagenomics and sporocarp sampling from natural stands of P. trichocarpa in Washington and Oregon and P. nigra in France. Based on our sampling we have identified a well-defined community of cottonwood associates, including specific members of Cortinarius, Hebeloma, Inocybe, Laccaria, Lactarius, and others. It is our objective to phylogenetically place these species within their generic/species complex context and investigate patterns of their host association in relation to their distribution. We hypothesize that host-restricted species are common associates of cottonwoods as they are co-evolved and selected by their host, whereas ECM invaders, or generalist ECM species, are diverse on cottonwoods but rare.

Abstract

Dementia is a neurodegenerative disease that has become one of the major issues in the 21th century. However, till date there is no specific treatment that can cure or prevent dementia from occurring in humans. Commercial drugs for dementia can only reduce the symptoms of the disease and even worse long term consumptions might pose adverse effects to other bodily functions. Therefore, this study aims to investigate the potential of Hericium erinaceus extracts to stimulate neurite outgrowth in PC12 cells. Briefly, fresh H. erinaceus was cut to cube, freeze dried and extracted with 20% w/v of 95% ethanol and overnight macerated with deionized water followed by 30min hot water extraction respectively. The crude extracts were rotary evaporated and freeze dried before the assay. PC12 cells were treated with 20ug/ml, 40ug/ml, 60 ug/ml and 80ug/ml of the extracts respectively. Neurite bearing score ranged between 2.5-29.6% with the highest score being 50ng/ml NGF treated cells. Pearson’s correlation showed positive correlation between extract concentration and neurite bearing score. Immunofluorescence assay was performed to confirm the neurite outgrowth via staining with rabbit anti-neurofilament 200 polyclonal antibody. The RNAs of the treated cells were also extracted to check the expression level of neurite outgrowth related gene, neuritin via qPCR. This would be the first report of neuritin gene expression following neurite outgrowth induced by mushroom extracts. Further test will be conducted to investigate the effect of co-incubation of H. erinaceus extract with 5ng/ml of NGF. In conclusion, H. erinaceus may be applied as potential health and functional food source in management of neuronal related diseases.

Abstract

Succession is variation of ecological communities involved by environmental changes. There are many types of succession caused by extreme stress factors such as volcanic eruptions, landslides, and floods, whereas a succession that occurs slowly over time. Odaesan National Park is well-preserved forest located in the Taebaek mountain range in South Korea. The forest succession of the national park is progressing from a mixed-wood forest to a hardwood forest. In this study, the microbial community composition was investigated using 454 sequencing of the soil samples collected from 13 different locations in Odaesan National Park. We assessed whether the communities are affected by environmental factors such as water contetnt (WC), nutrient availability (total carbon and nitrogen) and pH, which were caused by forest succession. As results, water content, total carbon (TC), total nitrogen (TN) and pH were statistically different according to the succession stages of the forest. WC, TC and TN of forest soils tended to increase as succession progressed, while pH tended to decrease. In both succession stages, the bacterial genus Pseudolabrys was most abundant, followed by Afipia and Bradyrhizobium. In addition, the fungal genus Saitozyma showed the highest abundance in the forest soils. The beta diversity of microbial communities was determined by NMDS analysis, which showed a clear discrimination of microbial communities according to forest succession stages, and soil properties (WC, TC, TN, and pH). Furthermore, a network analysis of both bacterial and fungal taxa showed the strong relationship of the microbial community depending on the soil properties caused by forest succession. Further study about functional profiling of each microbial components will help to understand the succession of forest ecology.

Abstract

The taxonomy and systematics of the Boletaceae have long been based on morphological species and genera concepts from Europe and North America. From about 2010 on, molecular (DNA) analyses including tropical boletes have started to profoundly change the systematics this group, with many new genera being published. This revolution is still ongoing, and the purpose of this paper is to present recent advances on Boletaceae systematics based on specimens collected in Thailand. We used both multi-gene phylogenetic analyses and morphological descriptions to better understand the systematics of Thai boletes. The most recent findings are two new genera, Chromatophyllum and Cacaoporus, and the identification of phylogenetic affinities of the genus Rhodactina. Chromatophyllum is a new phylloporoid genus forming a clade within the Pulveroboletus group, distant from the Phylloporus clade, which belong in the Xerocomoideae. Morphologically, Chromatophyllum can easily be distinguished from Phylloporus by the ovoid spores, lack of bacillate spore ornamentation, and deeply yellowish-orange to red lamellae. We described two new species of Chromatophyllum from Thailand, and recombined two Phylloporus species from the Americas in this new genus. Cacaoporus, which also belongs in the Pulveroboletus group, is unusual among Boletaceae in having a completely dark chocolate-brown hymenophore. Finally, with the discovery of a new Rhodactina species, R. rostratispora, we revealed the phylogenetic affinities of this truffle-like genus. It belongs in the Leccinoideae, and forms a well-supported clade with the other genera showing a purple color change of the spores when in contact with aqueous KOH solution, namely Borofutus and Spongiforma. The project is ongoing, and the impressive diversity of Boletaceae from Thailand might still bring interesting insights on the systematics and evolution of this family.

Abstract

Abstract

The ectomycorrhizospheric habitat contains a diverse pool of organisms, including the host plant, mycorrhizal fungi, and other rhizosphere microorganisms. Different signaling molecules may influence the ectomycorrhizal symbiosis.

Here, we show that the mutual symbiosis between the basidiomycete Tricholoma vaccinum and Norway spruce (Picea abies) shapes the surrounding mycorrhizosphere. In a forest biotope, this was characterized by a high diversity in basidiomycetes and a rich bacterial community. This consisted of mainly bacteria plant growth promoting abilities dominated by Rhizobiales, with Nitrobacter winogradski being most abundant (3.9 %). Other taxa mainly were pseudomonads and bacilli. The bacterial isolates showed symbiosis-relevant traits with 74 % producing the phytohormone indole-3-acetic acid, 23 % producing siderophores, and 23 % mobilizing phosphate.

The mycorrhizal fungus T. vaccinum was able to excrete plant hormones into the medium upon axenic cultivation. These include auxins, salicylic and abscisic acid, and jasmonates. The spruce roots exudated auxins and salicylic acid. With these compounds present in soil of a natural ectomycorrhizospheric habitat, a communication network with a response of T. vaccinum to the environmentally available salicylic and abscisic acids, which led to altered hyphal branching relevant for mycorrhization. In addition, the fungus protected the mycorrhizal tree against the spruce pathogens Botrytis cinerea and Heterobasidion annosum. Thus, the finely tuned phytohormone interactions in the mycorrhizosphere represent a specifically rich system to study microbial communication.