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81.
82.
83.
The putative ectomycorrhizal fungal species registered from sporocarps associated with ponderosa pine and Douglas-fir forests
in their natural range distribution (i.e., western Canada, USA, and Mexico) and from plantations in south Argentina and other
parts of the world are listed. One hundred and fifty seven taxa are reported for native ponderosa pine forests and 514 taxa
for native Douglas-fir forests based on available literature and databases. A small group of genera comprises a high proportion
of the species richness for native Douglas-fir (i.e., Cortinarius, Inocybe, and Russula), whereas in native ponderosa pine, the species richness is more evenly distributed among several genera. The comparison
between ectomycorrhizal species richness associated with both trees in native forests and in Patagonia (Argentina) shows far
fewer species in the latter, with 18 taxa for the ponderosa pine and 15 for the Douglas-fir. Epigeous species richness is
clearly dominant in native Douglas-fir, whereas a more balanced relation epigeous/hypogeous richness is observed for native
ponderosa pine; a similar trend was observed for Patagonian plantations. Most fungi in Patagonian Douglas-fir plantations
have not been recorded in plantations elsewhere, except Suillus lakei and Thelephora terrestris, and only 56% of the fungal taxa recorded in Douglas-fir plantations around the world are known from native forests, the
other taxa being new associations for this host, suggesting that new tree + ectomycorrhizal fungal taxa associations are favored
in artificial situations as plantations. 相似文献
84.
Zhang JM Sun JF Feng PY Li XQ Lu CM Lu S Cai WY Xi LY de Hoog GS 《Journal of microbiological methods》2011,85(1):33-39
Penicillium marneffei infection is a deadly disease and early diagnosis leads to prompt and appropriate antifungal therapy. To develop a sensitive method to diagnose P. marneffei infection, a multiplex ligation-dependent probe amplification (MLPA) assay was adapted. This method can rapidly and specifically detect P. marneffei DNA in cultured cells and paraffin-embedded tissue samples. Three pairs of probes were designed for amplifying the internally (intergenic) transcribed spacer (ITS) region of P. marneffei rRNA using a systematic phylogenetic analysis. These three probe sets produced three amplicons of 198, 166, and 152 bp, respectively, specific for P. marneffei. In contrast, there was only one 198 bp amplicon produced for Talaromyces stipitatus, and one 152 bp amplicon for P. funiculosum, T. intermedius and T. derxii. The probes did not amplify any other reference strains. An array of 40 P. marneffei strains isolated from human patients, bamboo rat, and the local environment was tested by using MLPA, and all were positively identified. Most importantly, P. marneffei in paraffin-embedded tissue specimens from infected human patients was positively amplified by MLPA. The sensitivity and specificity of the MLPA assay could be a useful tool for prompt diagnosis, pathogen characterization, and epidemiological studies of fungal infections. 相似文献
85.
葡萄种质资源初级核心群的构建 总被引:3,自引:0,他引:3
以国家果树种质郑州葡萄圃保存的867份栽培种质为材料,对47项表型性状进行了主成分分析。采用欧氏遗传距离、离差平方和法进行种质初选。采用分组和逐步聚类法,分别以15%、20%、25%和30%的比例抽样,依次获得124、170、205和252份种质。通过对初选种质的遗传多样性指数、表型保留比例的分析,检验初级核心群的构建效果。结果表明,按种质类型分组,组内采用平方根策略、15%抽样比例获得的124份初选种质的表型保留比例和遗传多样性代表性均达到96%,表明构建的初级核心群对原始种质具有很好的代表性。 相似文献
86.
M.?Awad?Shatnawi Krystyna?A.?JohnsonEmail author Fraser?R.?Torpy 《In vitro cellular & developmental biology. Plant》2004,40(4):403-407
Summary An efficient procedure for the in vitro propagation and cryogenic conservation of Syzygium francissi was developed. The maximum number of shoots per explant was obtained on a Murashige and Skoog (MS) medium supplemented with
4.5 μM benzyladenine and 0.5 μM indole-3-butyric acid (IBA). The in vitro-propagated shoots produced roots when transferred to MS medium containing IBA, indold-3-acetic acid, or naphthaleneacetic
acid at various concentrations. Rooted microshoots were transferred to a coco-peat, perlite, and vermiculite (1∶1∶1) mixture,
and hardened off under greenhouse conditions. Ninety-five percent of rooted shoots successfully acclimatized in the greenhouse.
Shoot tips excised from in vitro-grown plants were successfully cryostoraged at −196°C by the encapsulation-dehydration method. A preculture of formed beads
on MS medium containing 0.75 M sucrose for 1 d, followed by 6 h dehydration (20% moisture content) led to the highest survival rate after cryostorage for
1h. This method is a promising technique for in vitro propagation and cryopreservation of shoot tips from in vitro-grown plantlets of S. francissi germplasm. 相似文献
87.
Glomalean mycorrhizal fungi from tropical Australia 总被引:6,自引:0,他引:6
A comparison of different methods for isolation of vesicular-arbuscular mycorrhizal (VAM) fungi into open-pot cultures was
undertaken as part of a study of the diversity of these fungi. Four different isolation techniques using spores separated
from soil, soil trap cultures, root samples, or transplanted seedlings grown in intact soil cores were used to obtain as many
fungi as possible from each site. Isolation methods were compared using paired samples from the same locations within natural
(savanna, rocky hill, wetland, rainforest) and disturbed (minesite) habitats in a seasonally dry tropical region in the Northern
Territory of Australia. There were large differences in (i) the efficiency (rate of increase in mycorrhizal colonisation),
(ii) the proportion of successful cultures, (iii) fungal diversity (number of fungal species in each culture) and (iv) specificity
(identity of species isolated) between these four procedures. However, the less-efficient procedures generally resulted in
a higher proportion of cultures of one fungus, which could be used without further isolation steps. Most species of Scutellospora, Acaulospora and Gigaspora were obtained primarily from field-collected spores, but only 50% of these culture attempts were successful. Spores from
these initial cultures produced mycorrhizas much more rapidly and successfully when used to start second-generation cultures.
Several species of fungi, rarely recovered as living spores from field soils, were dominant in many trap cultures started
from soil or roots. Most of these fungi were Glomus species, that were first distinguished by colonisation patterns in roots and eventually identified after sporulation in second-
or third-generation trap cultures. These experiments demonstrated that glomalean fungi in the habitats sampled belonged to
two functional categories, based on whether or not spores were important propagules. The "non-sporulating" fungi were dominant
in many trap cultures, which suggests that these fungi had higher total inoculum levels in soils than other fungi. Pot-culturing
methods provided additional information on fungal diversity which complemented spore occurrence data obtained using the same
soil samples and provided valuable new information about the biology of these fungi.
Accepted: 26 December 1998 相似文献
88.
S SPIEGEL D HOLLAND Y TAM I BAR-YAAKOV L MASLENIN A ROSNER 《The Annals of applied biology》2004,144(2):229-236
Prunus necrotic ringspot virus (PNRSV) was detected in almonds, plum and apricot germplasm accessions and local almond cultivars in Israel. PNRSV was widespread both in wild and cultivated almond trees and uncommon in wild apricots and plums. The possible variation among the PNRSV isolates was initially evaluated by restriction analysis of PCR products representing the CP gene with the endonuclease RsaI and followed by nucleotide sequence analysis of selected isolates. It was concluded that all 13 isolates belong to group PV96, the largest cluster of PNRSV isolates, described previously. Two PNRSV isolates, one from a plum accession and one from an almond cultivar, were found to be distinct members of group PV96 with unique nucleotide modifications not found in other documented isolates of this virus. However, no PNRSV isolate typical to a specific host and/or to the Middle East region could be identified. This study expands the body of data on variability of PNRSV isolates and highlights the importance of assessing the virus status of germplasm collections by applying reliable diagnostic and differentiating methods. 相似文献
89.
Surendra K. Gond Ashish Mishra Vijay K. Sharma Satish K. Verma Jitendra Kumar Ravindra N. Kharwar Anuj Kumar 《Mycoscience》2012,53(2):113-121
Endophytic fungi from Nyctanthes arbor-tristis were isolated and evaluated for their antimicrobial activity. A total of 19 endophytic fungi were isolated from 400 segments
of healthy leaf and stem tissues of N. arbor-tristis. Eighteen endophytic fungi were obtained from leaf, while only ten from stem. Alternaria alternata had the highest colonization frequency (15.0%) in leaf, whereas Cladosporium cladosporioides ranked first in stem with a colonization frequency of 12%. The diversity and species richness were found higher in leaf tissues
than in stem. The similarity indices between leaf and stem were 0.473 for Jaccard’s and 0.642 for the Sorenson index, respectively.
Of 16, 12 (75%) endophytic fungal extracts showed antibacterial activity against either one or more pathogenic bacteria. The
endophytic Nigrospora oryzae showed maximum inhibition against Shigella sp. and Pseudomonas aeruginosa. The leaf endophytes Colletotrichum dematium and Chaetomium globosum exhibited a broad range of anibacterial activity and were active against Shigella flexnii, Shigella boydii, Salmonella enteritidis, Salmonella paratyphi, and P. aeruginosa. Nine out of 16 (56.25%) endophytic fungi exhibited antifungal activity to one or more fungal pathogens. Colletotrichum dematium inhibited 55.87% of the radial growth of the phytopathogen Curvularia lunata. The antimicrobial activity of these endophytic microorganisms could be exploited in the biotechnological, medicinal, and
agricultural industries. 相似文献
90.
以陈年小麦离体胚为外植体,MS培养基为基本培养基,附加5种植物生长物质2,4-D、NAA、KT、6-BA、GA3进行单因子和正交试验,研究植物生长物质在陈年小麦离体胚萌发中的作用。单因子试验结果表明:单独使用6-BA 1.0mg/L、GA3 2.5mg/L均能在一定程度上促进陈年小麦离体胚出芽和生根,出芽率分别为70.0%和77.5%,比对照分别提高了21.7%和29.2%;生根率分别为63.3%和72.2%,比对照分别提高了21.3%和30.2%。正交试验结果显示GA3对陈年小麦离体胚的萌发影响显著,最佳植物生长物质组合为2,4-D2.0mg/L NAA 1.1mg/L 6-BA0.5mg/L GA3 4.0mg/L,出芽率为82.5%,生根率为60.0%,比对照分别提高了32.5%和17.5%。 相似文献