scholarly journals Behaviour in cultures and habitat requirements of species within the genera Loreleia and Rickenella (Agaricales)

2013 ◽  
Vol 41 (2) ◽  
pp. 189-208 ◽  
Author(s):  
Andreas Bresinsky ◽  
Angelika Schötz

The term eco-geogram is introduced for surveying (in logical order) ecological and geographical data connected with fungal species. The database PILZOEK was established for that purpose. Eco-geograms are provided in this paper as an example for data retrieval from PILZOEK concerning the agarics <em>Loreleia marchantiae, L. postii, Rickenella swartzii</em> and <em>R. fibula</em>. The potential degree of endangerment is discussed in regard to habitat requirements. European species of <em>Loreleia</em> are not regarded to be endangered in Central Europe, although the risk to get threatened, because of low frequency of fruit body occurrence and quite a narrow substrate specialization, could be higher than in case of <em>Rickenella fibula</em> and <em>R. swartzii. Cultures of Rickenella fibula, R. swartzii, Loreleia marchantiae (= Gerronema daamsii)</em> and <em>L. postii</em> were investigated in regard to pigment accumulation, chlamydospore formation and some other characters.

2020 ◽  
Vol 287 (1919) ◽  
pp. 20192348 ◽  
Author(s):  
Jeffrey Diez ◽  
Håvard Kauserud ◽  
Carrie Andrew ◽  
Einar Heegaard ◽  
Irmgard Krisai-Greilhuber ◽  
...  

Many plant and animal species are changing their latitudinal and/or altitudinal distributions in response to climate change, but whether fungi show similar changes is largely unknown. Here, we use historical fungal fruit body records from the European Alps to assess altitudinal changes in fungal fruiting between 1960 and 2010. We observe that many fungal species are fruiting at significantly higher elevations in 2010 compared to 1960, and especially so among soil-dwelling fungi. Wood-decay fungi, being dependent on the presence of one or a few host trees, show a slower response. Species growing at higher elevations changed their altitudinal fruiting patterns significantly more than lowland species. Environmental changes in high altitudes may lead to proportionally stronger responses, since high-altitude species live closer to their physiological limit. These aboveground changes in fruiting patterns probably mirror corresponding shifts in belowground fungal communities, suggesting parallel shifts in important ecosystem functions.


2020 ◽  
Vol 2020 ◽  
pp. 1-11
Author(s):  
Yanduo Ren ◽  
Jiangbo Qian ◽  
Yihong Dong ◽  
Yu Xin ◽  
Huahui Chen

Nearest neighbour search (NNS) is the core of large data retrieval. Learning to hash is an effective way to solve the problems by representing high-dimensional data into a compact binary code. However, existing learning to hash methods needs long bit encoding to ensure the accuracy of query, and long bit encoding brings large cost of storage, which severely restricts the long bit encoding in the application of big data. An asymmetric learning to hash with variable bit encoding algorithm (AVBH) is proposed to solve the problem. The AVBH hash algorithm uses two types of hash mapping functions to encode the dataset and the query set into different length bits. For datasets, the hash code frequencies of datasets after random Fourier feature encoding are statistically analysed. The hash code with high frequency is compressed into a longer coding representation, and the hash code with low frequency is compressed into a shorter coding representation. The query point is quantized to a long bit hash code and compared with the same length cascade concatenated data point. Experiments on public datasets show that the proposed algorithm effectively reduces the cost of storage and improves the accuracy of query.


Author(s):  
A. D. Hawkins ◽  
Knud Just Rasmussen

Of nine northern European species of the Gadidae examined in the aquarium, or in cages in the sea, four produced sounds. The vocal species were the haddock, Melanogrammus aeglefinus (L.); the cod, Gadus morhua L.; the lythe, Pollachius pollachius (L.); and the tadpole-fish, Raniceps raninns (L.). The main differences between the calls of the vocal species lay in their temporal structure, all the calls being divisible into brief pulses of low frequency sound, repeated at different rates and in different groupings. Calls with this structure yielded spectra with a series of spaced harmonics, the frequency spacing depending upon the pulse repetition rate.Sixteen additional species were dissected, and seven of these showed well developed muscles attached to the swimbladder, similar to those found in the four vocal species. The remaining nine species, together with the five non-vocal species examined in the aquarium, lacked the muscles.The behavioural significance of the calls and the operation of the sound producing mechanism are discussed.


2001 ◽  
Vol 49 (3) ◽  
pp. 243-250
Author(s):  
C. I. Mónaco ◽  
H. Alippi ◽  
I. Mittidieri ◽  
A. I. Nico

Fungal isolations were made from leaves of tomato plants cultivated in greenhouses in an area close to La Plata, Argentina. Three different schemes of fungicide application were evaluated: high frequency preventive sprayings (Commercial Greenhouse I), low frequency preventive applications (Commercial Greenhouse II) and no fungicide spraying (Control Greenhouse). Leaves were sampled immediately after second fruit formation from three levels of the foliage: low, medium and high. Plating dilution was used to isolate fungal species. Total c.f.u. number and species composition and diversity were assessed by the plating dilution technique. Fungal populations were most abundant on leaves from lower parts of the foliage in the Control Greenhouse. Diversity varied according to fungicide application frequency and leaf position in the canopy. Higher values were recorded for lower leaves in the Control Greenhouse compared with upper leaves from Commercial Greenhouse II. Likewise position in the canopy influenced the frequency of some species. The implications for natural biological control are discussed. Key words: biodiversity, biological control, phylloplane, tomato


2009 ◽  
Vol 76 (5) ◽  
pp. 1642-1652 ◽  
Author(s):  
Zhi-lin Yuan ◽  
Chu-long Zhang ◽  
Fu-cheng Lin ◽  
Christian P. Kubicek

ABSTRACT Rice (Oryza sativa L.) is, on a global scale, one of the most important food crops. Although endophytic fungi and bacteria associated with rice have been investigated, little is known about the endophytic fungi of wild rice (Oryza granulate) in China. Here we studied the root endophytic mycobiota residing in roots of O. granulate by the use of an integrated approach consisting of microscopy, cultivation, ecological indices, and direct PCR. Microscopy confirmed the ubiquitousness of dark septate endophytes (DSEs) and sclerotium-like structures in root tissues. Isolations from 204 root segments from 15 wild rice plants yielded 58 isolates, for which 31 internal transcribed spacer (ITS)-based genotypes were recorded. The best BLAST match indicated that 34.5% of all taxa encountered may represent hitherto undescribed species. Most of the fungi were isolated with a very low frequency. Calculation of ecological indices and estimation of taxon accumulation curves indicated a high diversity of fungal species. A culture-independent approach was also performed to analyze the endophytic fungal community. Three individual clone libraries were constructed. Using a threshold of 90% similarity, 35 potentially different sequences (phylotypes) were found among 186 positive clones. Phylogenetic analysis showed that frequently detected clones were classified as Basidiomycota, and 60.2% of total analyzed clones were affiliated with unknown taxa. Exophiala, Cladophialophora, Harpophora, Periconia macrospinosa, and the Ceratobasidium/Rhizoctonia complex may act as potential DSE groups. A comparison of the fungal communities characterized by the two approaches demonstrated distinctive fungal groups, and only a few taxa overlapped. Our findings indicate a complex and rich endophytic fungal consortium in wild rice roots, thus offering a potential bioresource for establishing a novel model of plant-fungal mutualistic interactions.


2019 ◽  
Vol 30 (1) ◽  
pp. 29-32
Author(s):  
V. M. Pomohaibo ◽  
N. A. Vlasenko ◽  
L. D. Orlova

On the basis of the review of numerous scientific publications, in our article there is compared the effectiveness of various study methods of macrofungi groups, the species diversity of which remains largely unknown. Macrofungi form the visible fruit body. They are found in most environmental conditions, but are most common in forest ecosystems, where they are reducers. Macrofungi belong to the Ascomycota and Basidiomycota types within the Dikarya subkingdom and are divided into saprotroph, parasitic and mycorrhizal fungi. Saprotroph species play a main part in the decomposition of organic matter of soil, fallen leaves and dead wood. Parasitic macrofungi cause a number of diseases of other mushrooms, plants and animals (mostly invertebrates). Mycorrhizal fungi form a symbiotic system with plant roots, which is useful for both partners. There are known over 90000 species of macrofungi that is about 60 % of the number of all described fungal species in the present (Deacon, 2006; Orgiazzi et al., 2016). Macrofungi are considered to be studied in the best way, but their species diversity remains largely unknown. For example, in the course of over last 60 years more 56000 species of macrofungi have been identified in Australasia, China, and Japan, of which 35000 species, or 62 %, are unknown (Mueller et al., 2007). At the same time, in China and Japan the part of new macrofungal species was 37 %, and in Australasia – 72 %. To determine the diversity of macrofungi three methods can be used: a collections of fruit bodies, mycelium cultivation on the agar substrate and free fungal DNA in the environment. The study of collections are used most commonly. However, in the case when mushrooms have large fruit bodies, but they are short-lived, this method is not always able to detect them and attach them to the collection. For other two methods, the presence of fruit bodies is not obligatory. But the mycelium cultivation method also has a drawback, since not all mycorrhizal and parasitic mushrooms can be cultivated in the laboratory because they can’t exist outside the symbiosis with the roots of living plants or outside the host's body, respectively. Altogether together both collection studying and mycelium cultivation methods can find a significant majority of the environmental fungal taxons, which form fruit bodies. However, they can not reflect the relative prevalence of species. The method of molecular genetic analysis of the environmental DNA (eDNA) has the greatest advantages of other two, since it is also suitable for the discovery of such taxonomic units. This method has allowed to identify new branches, including ancient branched fungal lines, such as Cryptomycota or Archaeorhizomycetes. True, sometimes the method of eDNA analysis does not find taxonomic units, which are detected by the collection of fruit bodies or by mycelium cultivating. But this may have been due to sample incompleteness or to errors in the complex process of eDNA analysis. Since in these analysis there are used fragments of DNA or RNA only a few hundred bases long, this method is not able to detect a number of biological indices that can be obtained by examining of a fungal collection or culture. Thus to obtain most complete information about macrofungal community structure as well as their genomic, physiological and ecological properties it is necessary to use all three methods.


Author(s):  
Carrie Andrew ◽  
Einar Heegaard ◽  
Rune Halvorsen ◽  
Paul M Kirk ◽  
Klaus Høiland ◽  
...  

2021 ◽  
Vol 7 (3) ◽  
pp. 216
Author(s):  
Jan Dijksterhuis ◽  
Timon Wyatt ◽  
Micha Hanssen ◽  
Elena Golovina ◽  
Folkert Hoekstra ◽  
...  

Ascospores of Talaromyces.macrosporus belong to the most stress resistant eukaryotic cells and show a constitutive dormancy, i.e., no germination occurs in the presence of rich growth medium. Only an extreme trigger as very high temperature or pressure is able to evoke synchronized germination. In this study, several changes within the thick cell wall of these cells are observed after a heat treatment: (i.) a change in its structure as shown with EPR and X-ray diffraction; (ii.) a release of an abundant protein into the supernatant, which is proportional to the extent of heat activation; (iii.) a change in the permeability of the cell wall as judged by fluorescence studies in which staining of the interior of the cell wall correlates with germination of individual ascospores. The gene encoding the protein, dubbed ICARUS, was studied in detail and was expressed under growth conditions that showed intense ascomata (fruit body) and ascospore formation. It encodes a small 7–14 kD protein. Blast search exhibits that different Talaromyces species show a similar sequence, indicating that the protein also occurs in other species of the genus. Deletion strains show delayed ascomata formation, release of pigments into the growth medium, higher permeability of the cell wall and a markedly shorter heat activation needed for activation. Further, wild type ascospores are more heat-resistant. All these observations suggest that the protein plays a role in dormancy and is related to the structure and permeability of the ascospore cell wall. However, more research on this topic is needed to study constitutive dormancy in other fungal species that form stress-resistant ascospores.


2021 ◽  
Vol 4 (1) ◽  
pp. 9-16
Author(s):  
Suwardi Suwardi ◽  
Erik Ayatullah ◽  
Haidul Haidul

ABSTRAK Penelitian ini bertujuan untuk mengembangkan kit praktikum Elektronika Dasar II berbasis simulator Proteus untuk meningkatkan kemampuan pemecahan masalah mahasiswa.Hasil observasi dalam prapenelitian menunjukkan bahwa mahasiswa kesulitan merangkai komponen elektronika, kekurangan waktu praktikum, dan kesulitan dalam mendapatkan data.Untuk mengatasi permasalahan  ini dilakukan pengembangan kit praktikum Elektronika Dasar IIberbasis menggunakan simulator Proteus. Melalui kit praktikum mahasiswa fokus pada proses pengambilan data dan menganalisis sinyal keluaran rangkaian elektronika.Sedangkan simulator Proteus dapat membantu dalam mengamati gejala-gejala yang tidak dapat diamati langsung dan sebagai data pembanding. Penelitian ini merupakan jenis penelitian dan pengembangan dengan tahapan adalah analisis kebutuhan, pengembangan produk awal, validasi ahli, uji lapangan dan revisi produk. Penelitian ini dilakukan di Laboratorium Fisika FMIPA Universitas Bengkulu  semester ganjil 2018/2019dengan subyek penelitian ini adalah 22 mahasiswa. Pengumpulan data dilakukan menggunakan metode observasi dan kuesioner yang dianalisis secara deskriptif kuantitatif. Hasil penelitian menunjukkan bahwa kit praktikum yang berhasil dikembangkan terdiri dari delapan percobaan yaitu penguat common drain, common source, emitor ditanahkan, pushpull, respon frekuensi rendah, inverting dan non inverting, integrator dan diferensiator, dan filter aktif. Kelayakan kit praktikum sebagai media pembelajaran di laboratorium berdasarkan validasi ahli sebesar 82,50% (sangat layak) dan berdasarkan pengguna sebesar 82, 64% (sangat layak). Kata kunci: kit praktikum elektronika dasar II, simulator proteus, praktikum berbasis masalah  ABSTRACT This study aims to develop a Basic Electronics II practicum kit based on the Proteus simulator to improve students' problem solving abilities. The results of observations in the pre-study showed that students had difficulty assembling electronic components, lack of practicum time, and difficulties in obtaining data. To overcome this problem, the development of Basic Electronics II based practicum kit using the Proteus simulator is carried out. Through the practicum kit students focus on the process of data retrieval and analyzing the electronic circuit output signal. Whereas the Proteus simulator can help in observing symptoms that cannot be observed directly and as comparative data. This research is a type of research and development with stages are needs analysis, initial product development, expert validation, field testing and product revision. This research was conducted in the Physics Laboratory of the University of Bengkulu FMIPA odd semester 2018/2019 with the subjects of this study were 22 students. Data collection was carried out using observation methods and questionnaires which were analyzed quantitatively descriptively. The results showed that the practicum kit that was successfully developed consisted of eight experiments namely common drain amplifier, common source, ground emitter, pushpull, low frequency response, inverting and non-inverting, integrators and differentiators, and active filters. The feasibility of the practicum kit as a learning media in a laboratory based on expert validation is 82.50% (very feasible) and based on the user is 82, 64% (very feasible). Keywords: basic electronics II practicum kit, proteus simulator, problem solving laboratory


2020 ◽  
Vol 14 (3) ◽  
pp. 1801-1808
Author(s):  
Nawaf I. Alshammari ◽  
Vajid N. Veettil ◽  
Abdel Moneim E. Sulieman ◽  
S.L. Stephenson

Environmental factors such as temperature and humidity directly affect the growth and fruit bodies of fungi. We studied the diversity of wood decaying fungal species, which have grown on same substrate in forest as well as laboratory environment. Ten specimens of fruit body of wood-decaying fungi and 24 random pieces of coarse wooden debris were collected from the forest of northwest Arkansas. The samples of coarse woody debris were incubated in laboratory-growth chambers for two months to promote the fungal growth. Fourty-two different species of wood-decay fungal isolates were recovered and identified by internal transcribed spacer (ITS) region sequencing. The isolates from the forest belonged to twenty-two different taxa whereas twenty taxonomic groups were reported from the growth compartments. Remarkably, data observed from two sets did not shared any taxon. These results indicated that environmental growth conditions play crucial role on fungal diversity even if grown on same substrates.


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