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1.
 The ectomycorrhizae of Tomentella albomarginata are comprehensively described and compared to ectomycorrhizae of other Tomentella species and to ectomycorrhizae of some members of Thelephoraceae ss. Stalpers and Bankeraceae ss. Stalpers. The ectomycorrhizae of T. albomarginata are characterized by a hyphal net lying on a pseudoparenchymatous mantle surface, by tubular outgrowths of irregularly angular mantle cells, and by clamp-bearing emanating hyphae. Accepted: 15 July 1995  相似文献   

2.
Species in the subfamily Monotropoideae (family Ericaceae) are achlorophyllous and myco-heterotrophic. They have become highly specialized in that each plant species is associated with a limited number of fungal species which in turn are linked to autotrophic plants. This study provides an updated and comprehensive examination of the anatomical features of two species that have recently received attention with respect to their host-fungal specificity. Root systems of Monotropa uniflora and Pterospora andromedea collected from the field were characterized by light microscopy and scanning electron microscopy. All roots of both species were associated with fungi, each root having a well-developed mantle, paraepidermal Hartig net, and intracellular fungal pegs within epidermal cells. The mantle of M. uniflora was multi-layered and numerous outer mantle hyphae developed into cystidia of two distinct morphologies. Large calcium oxalate crystals were present, primarily on the mantle surface. The outer mantle of P. andromedea was more loosely organized, lacked cystidia, and had smaller plate-like as well as cylindrical crystals on the surface and between outer mantle hyphae. Fungal pegs in M. uniflora originated from inner mantle hyphae that penetrated the outer tangential wall of epidermal cells; in P. andromedea, these structures were initiated either from inner mantle hyphae or Hartig net hyphae and penetrated radial walls of epidermal cells. With respect to function, fungal pegs occurred frequently in both host species and, although presumed to be the sites of active nutrient exchange, no direct evidence exists to support this. Differences between these two monotropoid hosts, resulting from the mycorrhizal fungi with which each associates, are discussed.  相似文献   

3.
This paper presents Tomentella capitata and Tomentella brunneocystidia as new species based on molecular data and anatomical features. Both T. capitata and T. brunneocystidia form sister species with Tomentella pilosa. All three taxa are well supported by bootstrap values. Anatomically, T. capitata and T. brunneocystidia are very close and are similar in shape, size, ornamentation of basidiospores, and size and colour of subicular hyphae. Monomitic rhizomorphs sometimes covered by irregularly shaped thin hyphae are present in both species. Shape and pigmentation of the cystidia are the most discriminating features between T. capitata and T. brunneocystidia. The cystidia of T. capitata are maximum 35 μm long, show a distinctive globose apex and are sometimes covered with dark brown pigmentation and/or encrustation, whereas cystidia of T. brunneocystidia are bigger, up to 55 μm long, with a sub-capitate shape and dark blue to dark green contents all over their length. The differences to species, already described as having capitate and clavate cystidia, are discussed. A key for the identification of cystidioid Tomentella species is given. Taxonomical novelties: Tomentella capitata Yorou & Agerer, Tomentella brunneocystidia Yorou & Agerer.  相似文献   

4.
Hartig net structure and ontogeny were compared in ectomycorrhizae synthesized between the broad host range fungus, Laccaria bicolor and two hosts, Betula alleghaniensis and Pinus resinosa. In B. alleghaniensis, the Hartig net was present in the epidermis of the three ectomycorrhizal types formed, fast-growing first-order laterals with proximal colonization, clavate second-order laterals, and nonclavate second-order laterals. Root hair-fungus interactions occurred in this association. In P. resinosa, the Hartig net developed in epidermal and cortical cell layers of monopodial and dichotomously branched first-order laterals. Short monopodial laterals exhibited a mantle only. Fungal hyphae in the Hartig net exhibited a complex labyrinthine mode of growth in ectomycorrhizae of both tree species.  相似文献   

5.
The ectomycorrhiza (ECM) Piceirhiza internicrassihyphis on Picea abies is described in detail. It is yellowish brown to brown with a mantle of a transitional type between plectenchymatous and pseudoparenchymatous. The inner mantle layers show some thick-walled hyphae, often with a few of them growing in parallel. These thick-walled hyphae contain particles which turn brownish in Melzer’s reagent, and their septa and walls are partially amyloid. Rhizomorphs occur infrequently and are undifferentiated, and are composed of rather loosely woven hyphae of uniform diameter. This combination of characteristics has not yet been identified in any other ECM. The lack of cystidia and the presence of amyloidy suggest that this ECM is formed by a species of the family Thelephoraceae. Piceirhiza internicrassihyphis can be found associated with ECM of Cortinarius obtusus, and the hyphae of the latter species often grow on the surface of P. internicrassihyphis and can even cover the whole tip. Although there is a close association and possibly a penetration between these two fungi, it can be excluded that the thick-walled hyphae of the inner mantle layers originate from C. obtusus. Some emanating hyphae of C. obtusus ECM seem to interact with those of P. internicrassihyphis, as indicated by short, hyphal outgrowths which were found attached to the foreign hyphae.  相似文献   

6.
Guatemala is one of the richest biodiversity hotspots worldwide, bursting a wild array of ecosystems that range from pine and mixed forests in the highlands to tropical rain forests in the extensive El Petén area, bordering Belize and Mexico. Despite this biological wealth, however, current knowledge on the Guatemalan mycobiota is particularly scant, in part because of the prolonged civil war that has prevented exploration of many ecological niches. In the present paper, we report on the occurrence of Lactarius rimosellus Peck—a rarely discussed species—in oak-pine mixed forests in the Guatemalan highlands and describe the relevant ectomycorrhizae formed with Quercus sp. by means of molecular and morpho-anatomical tools. On the phylogenetic trees constructed on the basis of the partial LSU sequence, sporocarp- and ectomycorrhizae-derived sequences formed a common, statistically supported clade. The structural features of the ectomycorrhizae of L. rimosellus were generally found to match those described on various hosts for other Lactarius species belonging to the subgenus Russularia, where L. rimosellus has been traditionally assigned. These mycorrhizae are characterized by a pseudoparenchymatous outer mantle layer, with epidermoid or angular hyphal cells, and a plectenchymatous inner mantle layer; lactifers are embedded either in the middle and/or inner mantle layer. In the framework of a more general, ongoing study of the ethnomycology of the Maya populations in the Guatemalan highlands, we also report on the traditional knowledge about Lactarius mushrooms and their uses among native people.  相似文献   

7.
Ectomycorrhizal syntheses between Picea abies and the fungal associates Scleroderma citrinum, Boletus luridus, and Tricholoma vaccinum were carried out using Melin's Erlenmeyer flask technique. The symbioses of S. citrinum were characterized by a mantle composed of an outer prosenchymatous and an inner synenchymatous layer. The mantles of B. luridus and T. vaccinum were solely prosenchymatous. Rhizomorphs were produced in all treatments, but only in association with S. citrinum were they differentiated with additional, enlarged hyphae. All synthesized ectomycorrhizae were white or whitish to light orange and greyishorange. On large-scale root sampling in two differing Picea abies forests in Switzerland, nine out of a total of 22 morphological types of ectomycorrhizae were white or yellow in colour and were, therefore, comparable with the synthesized ectomycorrhizae. These nine natural types generally had distinct mantle features (irregular synenchyma, gelatinous matrix, cystides, thick-walled hyphae), but mostly lacked clamp connections. Synthesized ectomycorrhizae, on the other hand, lacked distinct mantle characteristics and always had clamp connections. Natural and synthesized white or yellow ectomycorrhizae did not coincide morphologically and thus identification of the fungal partners of natural symbioses by means of in vitro-synthesis with potential ectomycorrhizal fungi was not possible in the present study.  相似文献   

8.
 Laser scanning confocal microscopy (LSCM), light microscopy (LM) and epifluorescence microscopy (FM) were used to observe the extramatrical hyphae, mantle patterns and associated bacteria on mycorrhizal tips of Pinus strobus L. seedlings grown in pot cultures. Laccaria sp. and Tuber sp. formed ectomycorrhizas with Pinus strobus, while Phialophora finlandia Wang & Wilcox and E-strain (sensu Danielson 1982) formed ectendomycorrhizas. Distinct mantle patterns and cystidia were observed with greater resolution using LSCM, and intracellular hyphae were visualized in three dimensions. Trypan blue penetrated fresh whole mounts to 20 μm and was an excellent stain for visualizing fungal hyphae and bacteria with LSCM. Fluorescein isothiocyanate and acridine orange were used in conjunction with LSCM and FM to localize bacteria on ectomycorrhizal tips. With LSCM, bacteria were visible in the surface mucigel, and optical sectioning through the root tip showed that bacteria were also present within the mantle. LSCM is a non-intrusive and fast method for visualizing mycorrhizal structures and their associated bacteria on fresh, whole root tips. Accepted: 17 July 1996  相似文献   

9.
Two sebacinoid ectomycorrhizae on Chinese pine   总被引:1,自引:0,他引:1  
Sebacinoid fungi show a broad mycorrhizal capacity; therefore, they play a very important role in natural systems. Worldwide, fungi of Sebacinales are present under different environmental conditions and associate with diverse plant hosts, however, are hitherto poorly studied in China. Two sebacinoid ectomycorrhizae (ECM), Pinirhiza multifurcata and Pinirhiza nondextrinoidea, are described in detail morphologically and anatomically in the present study. They share a plectenchymatous outer mantle with multiply ramified hyphae in a gelatinous matrix, clampless, thin, thick-walled emanating hyphae with mostly Y-shaped ramifications and triangular inflations at the point of ramification. P. multifurcata and P. nondextrinoidea can be distinguished by thick cells in mantle layers, the ramification of emanating hyphae, the presence or absence of rhizomorphs, as well as the differing color reaction in Melzer's reagent. The putative molecular phylogenetic relationships of P. multifurcata and P. nondextrinoidea were inferred by analyses of the partial large subunit nuclear rDNA (nLSU); however, an affiliation to fungal species was not possible. This is the first report of sebacinoid ECM on Chinese pine.  相似文献   

10.
Fungal relationships and structural identity of their ectomycorrhizae   总被引:3,自引:0,他引:3  
Aproximately 5,000–6,000 fungal species form ectomyorrhizae (ECM), the symbiotic organs with roots of predominantly trees. The contributing fungi are not evenly distributed over the system of fungi. Within Basidiomycota exclusively Hymenomycetes and within Ascomycota exclusively Ascomycetes contribute to the symbiosis. Hymenomycetes play a big part, Ascomycetes a minor role; Zygomycetes only form exceptionally ECM. Responsible for ascomycetous ECM are mostly Pezizales with their hypogeous derivatives, whereas Boletales, Gomphales, Thelephorales, Amanitaceae, Cantharellaceae, Cortinariaceae, Russulaceae, and Tricholomataceae are the most important ectomycorrhizal relationships within Hymenomycetes. ECM, as transmitting organs between soil and roots, are transporting carbohydrates for growth of mycelium and fruitbodies from roots and have to satisfy the tree’s demand for water and nutrients. The latter task particularly influences the structure of ECM as nutrients are patchily distributed in the soil and saprotrophic as well as ectomycorrhizal fungi can act as strong competitors for nutrients. In focusing these requirements, ECM developed variously structured hyphal sheaths around the roots, the so-called mantles, and differently organized mycelium that emanates from the mantle, the so-called extramatrical mycelium. The mantles can be plectenchymatous consisting of loosely woven, differently arranged hyphae or they are densely packed, forming a pseudoparenchyma similar to the epidermis of leaves. The extramatrical mycelium grows either as simple scattered hyphae from the mantle into the soil or it can be united to undifferentiated rhizomorphs with a small reach or to highly organized root-like organs with vessel-like hyphae for efficient water and nutrient transport from distances of decimeters. Cystidia, sterile and variously shaped hyphal ends, possibly appropriate for preventing animal attack, in addition, can cover mantles and rhizomorphs. Although only a limited number of species could be considered, some general conclusions are possible.The genus Tuber forms needle-shaped cystidia and lacks rhizomorphs and clamps. Gomphales ECM are identified by rhizomorphs with ampullate inflations at septa of some hyphae and by oleoacanthocystidia or/and oleoacanthohyphae. Thelephoraceae reveal a great diversity of mantle structures and of extramatrical mycelium, with some additional optional characters, i.e., dark brown color, cystidia, blue granules, amyloid hyphae, or amyloid septa. Bankeraceae are mostly characterized by plectenchymatous mantles with star-like pattern and chlamydospores. Russulaceae possess smooth and hydrophilic ECM. Russula forms plectenchymatous mantles with knob-bearing cystidia, so-called russuloid cystidia, or pseudoparenchymatous mantles without cystidia. Lactarius lacks cystidia and shows laticifers within plectenchymatous or within pseudoparenchymatous mantles. The Boletales families Boletaceae, Gyroporaceae, Melanogastraceae, Paxillaceae, Rhizopogonaceae, Sclerodermataceae, and Suillaceae have the most advanced rhizomorph type, the so-called boletoid rhizomorphs, and reveal generally plectenchymatous mantles, frequently with ring-like patterns. Gomphidiaceae and Albatrellaceae provide cystidia, plectenchymatous mantles, and amyloidy; Gomphidiaceae are generally growing in ECM of Suillaceae and Rhizopogonaceae. Cortinariaceae reveal plectenchymatous mantles and undifferentiated or differentiated rhizomorphs or lack rhizomorphs at all. Cortinarius and Dermocybe are distinct by irregularly shaped, bent to tortuous ECM with many rhizomorphs, some growing over the mycorrhizal tip into the soil. Inocybe lacks rhizomorphs and its emanating hyphae are furnished by many secondary septa and prominent clamps with a hole. Rozites lacks rhizomorphs, too, and reveals a distinctly amyloid gelatinous mantle matrix. Descolea and Descomyces are covered by bolbitioid cystidia. Lastly, the genus Tricholoma forms plectenchymatous mantles and a high diversity of rhizomorphs. Some of the ectomycorrhizal features are used to hypothesize relationships at different taxonomic levels. These conclusions are compared with recently developed molecular hypotheses. Correspondence between the two types of hypotheses are evident, while some conflicts wait for a settlement.  相似文献   

11.
Morphological and ecological traits of the Mongolian grayling Thymallus brevirostrisfrom Hoton Nur Lake are investigated with consideration of the assumption for a possible presence in this species of two morpho-ecological forms. The data on growth, feeding, sex, and age composition are presented. Plastic and meristic characters, distribution of fish in the water body, and feeding are analyzed. Within the age range of 3+ to 6+, in the population there are two groups of specimens differing in growth rate, diet, and some plastic characters of the head. These two groups may be designated as “predatory” and “benthos-feeding” forms. The predatory form lacks specimens of junior age groups; the benthos_feeding form lacks specimens older than seven years. Validity of these morpho-ecological groups is discussed.  相似文献   

12.
Six groups of fossil remains of Kimberella quadrata are described. They represent the imprints of the body in different types of preservation (including the group of specimens that are elongated more than twice in comparison with the common ones) and also the feeding traces and mucus secretions. The imprint is considered to be created only by the upper side of the body. The fossil material shows that Kimberella had hard sclerites, probably of aragonite, and several teeth in its mouth. Kimberella is suggested to have “the mantle” with sclerites, wider foot, which was spread over the outer surface of the mantle, and the strong transverse and longitudinal musculature.  相似文献   

13.
Two skulls, two mandibles and some postcranials ofMesopithecus from the locality “Vathylakkos 2” of Axios Valley (Macedonia, Greece) enlarge our knowledge about the genus and its differentiation. The new material together with an old skull from the same locality is compared with the Pikermi, “Ravin des Zouaves 5” (Axios Valley), and Maramena (Serres basin) samples. It is concluded that the VathylakkosMesopithecus resemblesM. pentelicus from Pikermi, as wellM. delsoni from “Ravin des Zouaves 5” and it is referred asMesopithecus sp. aff.M. pentelicus. The biochronological age of “Vathylakkos 2” has been considered as MN 12, while recent magnetostratigraphic data indicate an age of about 7.5 Ma. This age confirms the position of the VathylakkosMesopithecus between Pikermi and “Ravin des Zouaves 5”. Some dental indices compared with those of the RecentCercopithecus suggest that the Vathylakkos sample is monospecific.   相似文献   

14.
Three genera of lagomorphs, Prolagus, Lagopsis, and “Amphilagus,” were identified during a revision of the lagomorph material from Sandelzhausen (MN5, Early/Middle Miocene boundary, southern Germany). Evidence of two morphological and dimensional classes were observed at some tooth positions in Prolagus (some p3 show an unmistakable P. oeningensis morphology, others closely resemble P. crusafonti), but not at other tooth positions (e.g., M1–2). Insufficient data from Sandelzhausen precludes identification of two different species of Prolagus from this locality, and to define the characteristics of the possible P. crusafonti-like species. Thus, all Prolagus specimens have been classified as P. aff. oeningensis. The genus Lagopsis is represented by L. cf. penai, whose presence is compatible with a MN5 age. The relative abundance of Lagopsis to Prolagus may indicate relatively cool and wet palaeoclimatic conditions. The largest primitive lagomorph species from continental Europe is present at Sandelzhausen. Morphological and dimensional comparisons with other European primitive lagomorphs exclude any affinity with the genera Eurolagus and Titanomys and with the species included in “Amphilagus ulmensis”. Some common features with “Amphilagus antiquus” were observed, although they are not sufficient for the attribution to this taxon. Until there is a general revision of European primitive lagomorphs, the Sandelzhausen giant lagomorph is classified as “Amphilagus” sp. Its origins, whether from evolution within Europe or migration from Asia, remain unknown.   相似文献   

15.
 In the present paper we report a mycorrhizal association between the hypogeous white truffle Terfezia terfezioides and the black locust (Robinia pseudoacacia) growing at various sites in Hungary. The mycorrhiza can be considered as being of the endo- or ectendo-type, since both mantle and Hartig net are absent. Morphological features of the septate hyphae colonizing cortical root cells were investigated by light microscopy on cryosections and on ultra-thin sections studied by transmission electron microscopy. Artificial infection of micropropagated black locust plantlets with the mycelium of the fungus was successful and had the same characteristics as naturally occurring associations. Accepted: 8 March 1996  相似文献   

16.
 A simple and reproducible in vitro system is described for the synthesis of Pisolithus-Eucalyptus grandis ectomycorrhizae. Hyphal discs from actively growing colonies were placed in large petri dishes containing minimum nutrient agar overlaid with cellophane and allowed to grow for 7 days. Seeds were then surface sterilized and placed above the expanding fungal colonies and the plates slanted. Seedlings that germinated and grew in the presence of fungal hyphae had twice as many lateral root tips as seedlings that germinated before they were transferred onto hyphal mats. In addition, the lateral root tips of inoculated seedlings had a faster maturation rate and emerged closer to the primary root apex than non-inoculated seedlings. All lateral tips emerged in contact with fungal hyphae and the differentiation of ectomycorrhizae was followed by examining lateral tips basipetally along a single primary root. Typical ectomycorrhizae had formed on 4-day-old lateral tips, i.e. a mantle, radially elongated epidermal cells and a Hartig net commencing about 0.3 mm behind the lateral root apex. Thereafter, the mantle continued to thicken and the apical meristem diminished. The Hartig net often surrounded the apex of 11- to 12-day-old lateral root tips. This model system will facilitate detailed studies on synchronized ectomycorrhizal development and associated molecular and biochemical changes. Accepted: 12 January 1996  相似文献   

17.
Traditional Knowledge and Management of Feijoa (Acca sellowiana) in Southern Brazil. This paper investigates traditional knowledge of the use and management of Acca sellowiana in southern Brazil. Fifty-six informants from three rural communities were assigned to one of four subgroups (“maintainers,” “managers,” “cultivators,” or “users”) based on their responses regarding management and use of A. sellowiana. Traditional knowledge related to use of this species is widespread among rural residents, but traditional knowledge related to management is fragmented depending on whether one uses, manages, or cultivates the species. Knowledge held in rural communities suggests that A. sellowiana could play an expanded role in local economies as well as biodiversity conservation. We suggest that participatory research could stimulate greater local use as well as on-farm conservation of A. sellowiana.  相似文献   

18.
The ectomycorrhizal status of Sistotrema sp. is shown by morphological–anatomical and molecular identification, confirming earlier reports about Sistotrema DNA in ectomycorrhizae (ECM). For molecular identification of the ECM nuclear rDNA ITS sequences obtained from mycorrhizal root tips and fruitbodies of Sistotrema sp. were compared. Blast searches using the Sistotrema sp. sequences as query were performed in GenBank and UNITE for comparison with previously published Sistotrema sequences. The morphological–anatomical characterization of the ECM used well-established protocols for the examination of all mantle parts and rhizomorphs in different sections and views including detailed illustrations. The ECM are irregularly monopodial–pyramidal, whitish ochre to yellow ochre, and woolly. Older ones become more greyish and silvery at some patches. Diagnostic anatomical characteristics are irregularly inflated emanating and rhizomorph hyphae, ampullately inflated clamps, and the occurrence of yellow drops within the hyphae. The plectenchymatous mantle shows ring-like arranged hyphae, and a slightly gelatinous matrix. The ECM of Sistotrema sp. are compared to those of other species that form distinctly ampullate hyphae in rhizomorphs, too. The anatomically most similar ECM to those of this Sistotrema specimen are those of Hydnum repandum.  相似文献   

19.
Tao N  Hu Z  Liu Q  Xu J  Cheng Y  Guo L  Guo W  Deng X 《Plant cell reports》2007,26(6):837-843
Citrus is an important fruit crop as regards accumulation of carotenoids. In plant carotenoid biosynthesis, phytoene synthase gene (Psy) plays a key role in catalyzing the head-to-head condensation of geranylgeranyl diphosphate molecules to produce colorless phytoene. In the present paper, we reported the phytoene contents determination and characterization of Psy during fruit ripening of “Washington” navel orange and its red-fleshed mutant “Cara Cara”. Results showed that phytoene was exclusively accumulated in peel and pulp of “Cara Cara”. Although phytoene was observed accumulating with fruit ripening of “Cara Cara”, the contents in pulp were 10 times higher than those in peel. The isolated two Psy cDNAs were both 1520 bp in full length, containing 436 deduced amino acid residues, with a different amino acid at 412th. Genomic hybridization results showed that one or two copies might be present in “Cara Cara” and “Washington” genomes. During “Cara Cara” and “Washington” fruit coloration, expression of Psy was observed to be up-regulated, as revealed by tissue specific profiles in the flavedo, albedo, segment membrane and juice sacs. However, Psy expression in albedo of “Cara Cara” was higher than that in “Washington”, as evidenced by phytoene accumulation in the peel.  相似文献   

20.
Tea plant [Camellia sinensis (L.) O.Kuntze)] is one of the most popular non-alcoholic beverage crops in the world today. In recent years, many clonal tea cultivars have been developed and widely planted to replace the diverse traditional tea populations. In this article, we study the relationships between classifications based on simple sequence repeat (SSR) markers and on morphological traits for 185 tea plant cultivars. Results show that the genetic diversity index (H) is between 0.229 and 0.803, and the mean value is 0.543; the observed heterozygosity (H o) ranges from 0.103 to 0.683, with an average of 0.340, while the genetic identity varies from 0.267 to 0.984. Based on tea-making properties, the genetic diversity in the “black-green tea” group is much higher than in the “Oolong tea” group. Based on morphological traits, cluster analysis classifies the 185 cultivars into three groups, “group I,” “group II” and “group III.” Most cultivars are related based on the geographical origin and their genetic backgrounds.  相似文献   

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