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1.
A simple in vitro system is described for the synthesis ofAbies firma-Cenococcum geophilum ectomycorrhizas. SterilizedA. firma seedlings on both MMN and FH media were inoculated with hyphal discs from actively growing margins ofC. geophilum colonies. Typical ectomycorrhizas formed on seedlings on FH medium after 3 mo of incubation. By light microscopy, the synthesized
mycorrhizas were seen to possess a thin mantle from which emanated extraradicle hyphae and highly branched, rarely septate
intracortical Hartig net mycelium, characteristic ectomycorrhizal features. This is the first report of aseptic ectomycorrhization
ofA. firma seedlings byC. geophilum. This model system will facilitate detailed studies on ectomycorrhizal development ofAbies species. 相似文献
2.
Four ectomycorrhizal fungi (Amanita muscaria,
Laccaria laccata,
Piloderma croceum and Pisolithus tinctorius) were used to produce mycorrhiza on seedlings and micropropagated plants of Castanea sativa in vitro. Pisolithus tinctorius was most effective in colonizing roots of both micropropagated plants and seedlings. A. muscaria and L. laccata only colonized a few feeder roots of some plants and Piloderma croceum did not form mycorrhizas. Mycorrhization of micropropagated plants increased survival and growth during weaning.
Accepted: 27 February 1996 相似文献
3.
Ability of native ectomycorrhizal fungi from northern Spain to colonize Douglas-fir and other introduced conifers 总被引:1,自引:0,他引:1
Thirty-six isolates from 27 species of native ectomycorrhizal fungi collected in northern Spain were tested for ectomycorrhiza
formation with Pseudotsuga menziesii seedlings in pure culture syntheses. Thirteen of those species were also tested for ectomycorrhiza formation with six other
species of conifers (two native and four introduced) to compare their colonization potential. Twenty-three fungal isolates
from 18 species formed ectomycorrhizas with Pseudotsuga menziesii. The colonization level of the root system varied markedly among the different fungal species. Eight fungi colonized over
50% of the short roots. Nine fungi did not form ectomycorrhizas even though some of them were collected in pure stands of
Pseudotsuga menziesii. Laccaria laccata, Lyophyllum decastes, Pisolithus tinctorius, and Scleroderma citrinum formed abundant ectomycorrhizas on all the conifers tested. Lactarius
deliciosus, Rhizopogon spp., and Suillus luteus showed the greatest host specificity. The success in the introduction of some exotic conifers for reforestation in northern
Spain is discussed in relation to their compatibility with native ectomycorrhizal fungi.
Accepted: 28 August 1995 相似文献
4.
Paul C. F. Tam 《Mycorrhiza》1995,5(3):181-187
Five ectomycorrhizal fungi, Pisolithus tinctorius, Thelephora terrestris, Cenococcum geophilum, Hymenogaster sp. and Scleroderma sp., which were demonstrated previously to be capable of forming ectomycorrhizas with some pine, eucalypt and fagaceous tree species were grown in vitro in liquid cultures for 3 weeks at six different concentrations of nine heavy metals, aluminium, iron, copper, zinc, nickel, cadmium, chromium, lead and mercury. Measurements of mean mycelial dry weight yields indicated that the local isolates of Hymenogaster sp. and Scleroderma sp., as well as the introduced fungal species P. tinctorius, were able to withstand high concentrations of Al, Fe, Cu and Zn and might, therefore, have potential for revegetation schemes in metal-contaminated soils. The metal amelioration mechanism in the metal-tolerant fungal species P. tinctorius was observed to involve extrahyphal slime and, as demonstrated by energy-dispersive X-ray spectrometry, was achieved by polyphosphate linkage of Cu and Zn. 相似文献
5.
The inoculation ofEucalyptus pilularis seedlings withPisolithus tinctorius and the subsequent development of ectomycorrhizas, led to an improved acquisition of phosphorus (P) from three different sources of P. These sources included insoluble phytate. Dry weight gain of seedlings was increased by inoculation in those treatments where growth was limited by P supply. 相似文献
6.
Luciana da Silva Rodrigues Maria Catarina Megumi Kasuya Arnaldo Chaer Borges 《Mycorrhiza》1999,8(5):263-266
We studied the viability of fragmented mycelium of Pisolithus
tinctorius and Paxillus
involutus entrapped in calcium alginate gel to determine the efficacy of this method of producing ectomycorrhizal fungus inoculum.
Fungi were grown in MMN solution at 28 °C before being fragmented in a blender and subsequently entrapped in calcium alginate.
We tested different ratios of alginate and mycelium suspension to 0.7 M CaCl2. The ratio 8 : 10 resulted in well-formed beads of the highest viability for Paxillus involutus (99%) and for Pisolithus tinctorius (75%). Paxillus
involutus mycelium was more than 90% viable when entrapped mycelium was 10 to 50 days old, and Pisolithus tinctorius attained its highest viability (55%) for 20- to 40-day-old mycelium. Gel entrapped Paxillus
involutus mycelium grew well at all temperatures after 30 days of storage, but viability significantly decreased after 60 days storage
at 6 °C on dry filter paper. For gel-entrapped Pisolithus tinctorius mycelium, viability was highest when stored at 25 °C in 0.7 M CaCl2. Entrapment of Paxillus
involutus fragmented mycelium in calcium alginate beads under the conditions that we propose can be used successfully to produce inoculum.
Accepted: 11 October 1998 相似文献
7.
Ectomycorrhizin Synthesis and Polypeptide Changes during the Early Stage of Eucalypt Mycorrhiza Development 总被引:9,自引:0,他引:9
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In functioning eucalypt ectomycorrhizas, biochemical alterations are accompanied by a differential accumulation of polypeptides including the synthesis of symbiosis-related proteins (JL Hilbert, Martin FM [1988] New Phytol 110: 339-346). In the present study, protein biosynthesis in the early stages of ectomycorrhiza formation on Eucalyptus globulus subsp. bicostata Kirkp. was examined using compatible and incompatible isolates of the basidiomycete Pisolithus tinctorius (Coker & Couch). Changes in polypeptide composition were observed within hours following contact of the compatible mycelium with the roots, well before the differentiation of typical symbiotic tissues. At this stage, at least seven symbiosis-related proteins (ectomycorrhizins) accumulated in root tissues. In vivo incorporation of [35S]methionine by ectomycorrhizas followed by electrophoresis of the labeled proteins revealed that most of these differences in polypeptide concentrations, including the ectomycorrhizin accumulation, are the result of differential protein biosynthesis rather than posttranslational modifications of the polypeptides. The initial development of eucalypt ectomycorrhizas, therefore, coincides with the synthesis of symbiosis-related proteins and the data presented here provide essential evidence to ascribe a functional developmental role to these proteins. 相似文献
8.
Ectomycorrhizas of naturally grown Momi fir (Abies firma) seedlings were characterized based on morphological features of fungal partners. A total of 128 seedlings were collected
over three years (1995–1997) from a 10×30 m plot where occurrences of ectomycorrhizal fungal fruitbodies were monitored for
the same period. Thirty-seven morphologically distinct ectomycorrhizal types were distinguished based mainly on the color
of ectomycorrhizas and the characteristics of fungal mantles. Type 37 was thought to beCenococcum geophilum because of the jet-black mycorrhizas and the characteristic structure of mantle surfaces. For half of the classified morphotypes,
fungal partners were inferred to be the generaLactarius, Russula, andTuber, and unidentified Basidiomycetes, based on earlier references. 相似文献
9.
Single isolates of a mycobiont isolated from Pisonia grandis R. Br., Pisolithus tinctorius (Pers.) Coker & Couch and Tylospora fibrillosa (Burt.) Donk were compared with regard to their relative abilities to produce key enzymes of inorganic nitrogen assimilation.
Nitrate reductase (NR) activities in the P. grandis mycobiont and T. fibrillosa were significantly lower than in P. tinctorius. While specific activities for glutamate dehydrogenase (GDH) were higher in P. tinctorius than the other two fungi following NH4
+ pre-treatment, glutamine synthetase (GS) activity did not differ significantly between the three fungi. In all three fungi,
specific activities for GS were significantly higher than for GDH. NR activity was expressed in all three fungi regardless
of the nitrogen source in the medium, but in P. tinctorius diminished following continued exposure to either NO3
–, NH4
+, glutamine or NO3
– + glutamine. The data are discussed in relation to nitrogen utilisation by the P. grandis mycobiont.
Accepted: 16 October 1997 相似文献
10.
Twenty Pisolithus tinctorius isolates from different geographic locations and different hosts were characterized by the random amplified polymorphic DNA
technique. Thirteen arbitrary primers generated 87 DNA fragments, all of them polymorphic. These data were used to calculate
genetic distances among the isolates. The pairwise genetic distances ranged from 1 to 100%, with an average of 58.7%. Cluster
analysis based on the amplified fragments grouped the isolates according to their host and geographical origins. Group I contained
isolates collected in Brazil and group II those collected in the Northern Hemisphere. In addition to the diversity seen at
the molecular level, the isolates also showed host specificity. Greenhouse experiments demonstrated that isolates from the
Northern Hemisphere colonized mainly Pinus whereas isolates from Brazil colonized only Eucalyptus. The molecular data suggest that the Pisolithus tinctorius isolates analyzed belong to two distinct groups. The data also suggest new guidelines for future investigations on the taxonomy
and systematic of this important fungus species. Furthermore, these results support future experiments aimed at the selection
and development of improved isolates of P. tinctorius.
Accepted: 3 October 1997 相似文献
11.
Acioli-Santos B Sebastiana M Pessoa F Sousa L Figueiredo A Fortes AM Baldé A Maia LC Pais MS 《Current microbiology》2008,57(6):620-625
12.
Summary A method for in vitro synthesis of mycorrhizae on coniferous tree seedlings is described. Tree seedlings (Larix decidua Mill., Picea abies (L.) Karst, and Pinus sylvestris L.) and fungi Amanita muscaria (L. ex Fr.) Hooker, Piloderma croceum Erikss. et Hjorst., Pisolithus tinctorius (Pers.) Coker et Couch, and Suillus grevillei (Klotzsch) Singer were maintained under sterile conditions in petri dishes. Typical ectomycorrhizae were established within 2–3 weeks after inoculation and within 2 months after germination of seedlings. Eventually a high percentage of mycorrhizal root tips was obtained. 相似文献
13.
We studied the tolerance of ectomycorrhizal (ECM) fungi to sodium chloride (NaCl) to find the best fungus to aid growth of
Pinus thunbergii. Four ECM fungi, Cenococcum geophilum, Pisolithus tinctorius, Rhizopogon rubescens, and Suillus luteus, were grown in liquid MMN media with five different concentrations of NaCl for 30 days, and their mycelial weights were determined.
Mycelial weights of P. tinctorius and R. rubescens were not significantly different between 0 mM and 200 mM, whereas those of C. geophilum and S. luteus decreased with increasing NaCl concentration, indicating that the former two species were more tolerant to higher NaCl concentrations
than the latter species. We further studied the intraspecific differences in NaCl tolerance of nine P. tinctorius isolates. They were grown on MMN agar media with six different concentrations of NaCl for 21 days, and their radial growth
was measured. In total, the hyphal growth at 25 mM NaCl was significantly higher than those at the other NaCl concentrations,
and EC50 values were confirmed at between 50 mM and 200 mM. Among the isolates, Pt03 and Pt21 showed measurable growth at 200 mM;
the growth of Pt03 was not significantly different between 0 mM and 200 mM. The results indicate that there are intraspecific
variations in NaCl tolerance of Pisolithus species. 相似文献
14.
Interactive competition of Pisolithus tinctorius (Pers.) Coker et Couch with an unidentified species Tanashi 01 and Suillus luteus (L.: Fr.) S. F. Gray was investigated using a rhizobox. Pinus densiflora Sieb. et Zucc. was used as the host plant and mycelia were distinguished by hyphal color. The speed of mycelial spread differed
between the fungi;P. tinctorius and Tanashi 01 grew faster than S. luteus. A P. tinctorius mycorrhizal seedling and a Tanashi 01 mycorrhizal seedling were transplanted on opposite sides of the rhizobox. The mycelia
and mycorrhizae of P. tinctorius were overgrown by Tanashi 01 hyphae and development of P. tinctorius was gradually inhibited. The areas occupied by mycelia and mycorrhiza of P. tinctorius decreased by 52% and 37%, respectively, 154 days after transplantation relative to that at 91 days. In the overlap area of
P. tinctorius and Tanashi 01, the latter fungus infected new root tips emerging from P. tinctorius mycorrhiza, which lacked a mantle of P. tinctorius hyphae, and formed a composite mycorrhizal structure. P. tinctorius mycorrhizae were progressively replaced by Tanashi 01 mycorrhizae. Mycelial spread of P. tinctorius and S. luteus were naturally inhibited but there was no interaction in mycorrhizal formation.
Accepted: 18 June 1999 相似文献
15.
Uwe Nehls Thierry Béguiristain Frank Ditengou Frédéric Lapeyrie Francis Martin 《Planta》1998,207(2):296-302
16.
As many eucalypts in commercial plantations are poorly ectomycorrhizal there is a need to develop inoculation programs for
forest nurseries. The use of fungal spores as inoculum is a viable proposition for low technology nurseries currently producing
eucalypts for outplanting in developing countries. Forty-three collections of ectomycorrhizal fungi from southwestern Australia
and two from China, representing 18 genera, were tested for their effectiveness as spore inoculum on Eucalyptus globulus Labill. seedlings. Seven-day-old seedlings were inoculated with 25 mg air-dry spores in a water suspension. Ectomycorrhizal
development was assessed in soil cores 65 and 110 days after inoculation. By day 65, about 50% of the treatments had formed
ectomycorrhizas. By day 110, inoculated seedlings were generally ectomycorrhizal, but in many cases the percentage of roots
colonized was low (<10%). Species of Laccaria, Hydnangium, Descolea, Descomyces, Scleroderma and Pisolithus formed more ectomycorrhizas than the other fungi. Species of Russula, Boletus, Lactarius and Hysterangium did not form ectomycorrhizas. The dry weights of inoculated seedlings ranged from 90% to 225% of the uninoculated seedlings
by day 110. Although plants with extensively colonized roots generally had increased seedling growth, the overall mycorrhizal
colonization levels were poorly correlated to seedling growth. Species of Laccaria, Descolea, Scleroderma and Pisolithus are proposed as potential candidate fungi for nursery inoculation programs for eucalypts.
Accepted: 7 May 1998 相似文献
17.
The effectiveness of 16 fungal isolates in forming ectomycorrhizas and increasing the growth and phosphorus uptake of Eucalyptus globulus Labill. and E. diversicolor F. Muell. seedlings was examined in the glasshouse. Seedlings were grown in yellow sand at 2 phosphorus levels (4 and 12 mg P kg-1 sand). At the time of harvest (100 days), the non-inoculated seedlings and seedlings inoculated with Paxillus muelleri (Berk.) Sacc. and Cortinarius globuliformis Bougher had a low level of contamination from an unknown mycorrhizal fungi. Seedlings inoculated with Thaxterogaster sp. nov. and Hysterangium inflatum Rodway had developed mycorrhizas of the superficial type whereas Hydnangium carneum Wallr. in Dietr., Hymenogaster viscidus Massee & Rodway, Hymenogaster zeylanicus Petch, Setchelliogaster sp. nov., Laccaria laccata (Scop. ex. Fr.) Berk., Scleroderma verrucosum (Vaillant) Pers., Amanita xanthocephala (Berk.) Reid & Hilton, Descolea maculata Bougher and Malajczuk and Pisolithus tinctorius (Pers.) Coker & Couch formed typical pyramidal ectomycorrhizas. The dry weight of non-inoculated and inoculated E. globulus seedlings at 12 mg P kg-1 sand did not differ, whereas several isolates caused growth depression of E. diversicolor. By contrast, at 4 mg P kg-1 sand growth increases ranged from 0–13 times above that of non-inoculated seedlings. P. tinctorius produced the largest growth increase on both eucalypt species. In general, isolates which developed more extensive mycorrhizas on roots produced the largest growth responses to inoculation. Isolates which increased plant growth also increased phosphorus uptake by the plant. Seedlings inoculated with L. laccata and S. verrucosum retained more phosphorus in their roots than plants inoculated with the other fungal isolates. 相似文献
18.
Summary Eight isolates of ectomycorrhizal fungi namely, Laccaria fraterna (EM-1083),Laccaria laccata (EM-1191), Pisolithus tinctorius (EM-1081),Pisolithus tinctorius (EM-1293), Scleroderma cepa (EM-1233),Scleroderma flavidum (EM-1235),Scleroderma verucosum, (EM-1283) and Hysterangium incarceratum (EM-1185) were grown on specially designed cocktail media prepared by adding various concentrations of different heavy metals namely Al, As, Cd, Cr, Ni and Pb. The heavy metals were selected keeping in view their relative abundance in coal ash and potential toxicity. The fungal isolates were grown on such designed cocktail media. The colony diameter was used for the measurement of the fungal growth. Total heavy metal accumulated in the mycelia was assayed by atomic absorption spectrophotometry.In relation to metal tolerance ability in general,Hysterangium incarceratum (EM-1185) showed maximum tolerance with respect to growth, Laccaria fraterna (EM-1083) and Pisolithus tinctorius (EM-1293) also showed considerable tolerance to the heavy metals tested. In relation to metal uptake in particular, Pisolithus tinctorius (EM-1293), has reported maximum uptake of Al (34642.58 ppm), Cd (302.12 ppm) and Pb (3501.96 ppm). In Laccaria fraterna (EM-1083), As (130.57 ppm) and Cr (402.38 ppm) uptake was recorded maximum; and Hysterangium incarceratum (EM-1185) has recorded maximum Ni (2648.59 ppm) uptake among the three suitable isolates documented here. 相似文献
19.
Changes in the activity of enzymes involved with primary nitrogen metabolism due to ectomycorrhizal symbiosis on jack pine seedlings 总被引:4,自引:0,他引:4
Jack pine (Pinus banksiana Lamb.) seedlings were inoculated with either one of the ectomycorrhizal (ECM) fungi, Laccaria bicolor (Maire) Orton or Pisolithus tinctorius (Pers.) Coker and Couch, and grown for 16 weeks in a growth chamber along with non-ECM controls. Five enzymes involved with the assimilation of nitrogen or the synthesis of amino acids were measured in the 3 jack pine root systems as well as in the pure fungal cultures. Pisolithus tinctorius in pure culture had no detectable activity of nitrate reductase (NR. EC 1.6.6.1), glutamate dehydrogenase (GDH. EC 1.4.1.2), glutamate decarboxylase (GDCO. EC 4.1.1.15) or glutamate oxoglutarate aminotransferase (GOGAT, EC 1.4.1.13) but did have some glutamine synthetase (GS, EC 6.3.1.2) activity. Laccaria bicolor in pure culture had no NR activity, small levels of GDCO activity, and high GS, GDH and GOGAT activity. The high levels of enzymatic activity present in L. bicolor indicate that it may play a greater role in the nitrogen metabolism of its host plant than P. tinctorius. ECM infection clearly altered the enzymatic activity in jack pine roots but the nature of these changes depended on the fungal associate. Non-ECM root systems had higher specific activities than ECM root systems for NR, GS, GDH and GDCO but GOGAT activites were the same for both the ECM and non-ECM roots. Root systems infected with L. bicolor had significantly greater NR and GDCO activity than those infected with P. tinctorius. Differences in the GS activity of the two fungi in pure culture corresponded to the GS activity of jack pine roots in symbiotic association with these fungi. While the free amino acid profiles in roots were significantly affected by ECM infection, the profile of free amino acids exported to the stem was the same for all treatments. High asparagine and low glutamine in roots infected with P. tinctorius indicates that asparagine synthetase (EC x.x.x.x) activity should be higher within this symbiotic association than in the L. bicolor association or in the non-mycorrhizal roots. 相似文献
20.
The complex interactions that occur in systems with more than one type of symbiosis were studied using one isolate of Bradyrhizobium sp. and the ectomycorrhizal fungus Pisolithus tinctorius (Pers.) Coker and Couch inoculated on to the roots of Acacia holosericea A. Cunn. ex G. Don in vitro. After a single inoculation with Bradyrhizobium sp., bacteria typically entered the roots by forming infection threads in the root hair cells via the curling point of the root hair and/ or after intercellular penetration. Sheath formation and intercellular penetration were observed on Acacia roots after a single inoculation with Pisolithus tinctorius but no radial elongation of epidermal cells. Simultaneous inoculation with both microorganisms resulted in nodules and ectomycorrhiza on the root system, occasionally on the same lateral root. On lateral roots bearing nodules and ectomycorrhiza, the nodulation site was characterized by the presence of a nodule meristem and the absence of an infection thread; sheath formation and Hartig net development occurred regularly in the region of the roots adjacent to nodules. Prior inoculation with Bradyrhizobium sp. did not inhibit ectomycorrhizal colonization in root segments adjacent to nodules in which nodule meristems and infection threads were clearly present. Conversely, in ectomycorrhizae inoculated by bacteria, the nodule meristem and the infection thread were typically absent. These results show that simultaneous inoculation with both microorganisms inhibits infection thread development, thus conferring an advantage on fungal hyphae in the competition for infection sites. This suggests that fungal hyphae can modify directly and/or indirectly the recognition factors leading to nodule meristem initiation and infection thread development. 相似文献