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1.
Summary Two new species ofTrichophyton, T. indicum andT. evolceanui, isolated from soil in India by the hair baiting technique, are described.T. indicum is characterized by its flat colony and delicately roughened microconidia. It is common and widely distributed in soil in India. T. evolceanui can be distinguished fromT. indicum by its heaped and folded colony on tomato juice agar and its echinulate and obovate microconidia which are consistently wider than those ofT. indicum on the various culture media tested.T. evolceanui also differs fromT. indicum in producing perforating organs on hair in vitro soil culture. It has restricted occurrence in Indian soils.  相似文献   

2.
Summary Out of 750 soil samples collected from various regions of Romania, during 1958–1967, a positive percentage of 86 was positive for keratinophilic fungi. Among the 13 isolated species, the most prevalent wereM. gypseum (54.6 %),C. keratinophilum (40.1 %) andK. (T.)ajelloi (27 %). BesideT. terrestre, found in 8.9 % of the examined soil samples, the percentage of the remaining species is low, not exceeding 4 %. In order of frequency:C. (T).evolceanui (3.2 %),M. cookei (2.2 %),T. mentagrophytes (2 %),T. quinckeanum (0.9 %),C. (T.)indicum (0.6 %). There have been also isolated, but only once;M. canis, A. multifidum, T. georgiae andT. vanbreuseghemii.The studies carried out on the immunobiological properties of the Romanian soil isolates (including intracutaneous tests, serological reactions and therapeutic efficiency), have showed a close relationship between these fungi and the common pathogenic dermatophytes. The pathogenic power of the keratinophilic fungi is briefly discussed.  相似文献   

3.
The inhibitors present in the extracts ofCinchoma ledgeriana, Emblica officinalis, Chrysobalanus C. icaco andTerminalia chebula were heat-stable, resistant to autoclaving, aging and desiccation for a week. However, they did not withstand dialysis for 48 hrs (exceptT. chebula extract.) These four extracts markedly inhibited the virus even on dilution in the ratio of 1?1 but viral infectivity was sharply reduced at higher dilutions in each case. Moreover, the inhibitors in the stem bark extract ofC. ledgeriana, fruit pericarp extract ofE. officinalis andT. chebula were highly inhibitory even at pH 10·0, whereas inhibition of the virus by leaf extract ofC. icaco was reduced to 24 per cent only at the same pH. The inhibitors in these four extracts were found to be probably not proteinaceous in nature, when precipitated with ammonium sulphate and ethanol.  相似文献   

4.
Storage of nematodes in soil at -15 C for 1 to 16 weeks greatly increased nematode recovery by a sugar-flotation-sieving procedure. One week of exposure to -15 C killed all nematodes except Pratylenchus zeae and Tylenchorhynchus claytoni which were recoverable in decreasing numbers up to 10 weeks by the Baermann funnel method. Optimum storage temperature for survival of most nematode species was 13 C. The numbers of Meloidogyne incognita, T. claytoni, Belonolaimus Iongicaudatus, and P. zeae recoverable by either extraction method remained constant or increased when stored at 13-24 C for 16 weeks. This was also true for Helicotylenchtts dihystera and Xiphinema americanum extracted by the Baermann funnel technique, whereas the numbers retrieved by the sugar-flotation-sieving method decreased slightly. All species except T. claytoni decreased appreciably in soil stored at 36 C.  相似文献   

5.
Anaerobic conditions in soil commonly occur even in upland environments. Physiological and biogeochemical properties of individual anaerobic bacteria, however, have been poorly understood due to difficulties in culture. This study aimed to isolate anaerobic bacteria in the Arctic tundra soil and to identify their physiological characteristics. Anaerobic culture and 16S rRNA gene sequence-based phylogenetic analysis showed that total 33 bacterial strains were affiliated with 15 species from the following 8 genera: Bacillus, Carnobacterium, Clostridium, Paenibacillus, and Trichococcus (Firmicutes), Pseudomonas and Rahnella (Gamma-proteobacteria), and Cellulomonas (Actinobacteria). All isolates were identified as facultatively anaerobic bacteria; this finding might be partially attributed to the characteristics of sampling sites, which temporarily developed anaerobic conditions because of the presence of stagnant melting snow. Six of the 33 bacterial strains were revived subsequently from glycerol stocks held ?80 °C, and these were used for the physiological study: four isolates from Firmicutes, one isolate from Gamma-proteobacteria, and one isolate from Actinobacteria. Five isolates except KOPRI 80146 (Bacillus sp.) could grow at either 4 or 10 °C within a week. All six isolates showed cellulase or protease activities at 10 or 15 °C. Endospores were observed from four isolates belonging to Firmicutes. These physiological characteristics may contribute to the survival of these organisms at low temperatures and to their involvement in biogeochemical cycles in the tundra soil. These isolates may be used for further detailed studies for identifying their cold adaptation mechanisms and ecological roles in the Arctic.  相似文献   

6.
Summary Growth response to griseofulvin has been studied in 24 strains of 16 species of geophilic dermatophytes and related keratinophilic fungi. Based on their sensitivity to griseofulvin these fungi fall into three groups: (1) Resistant group includesKeratinomyces ajelloi, Trichophyton terrestre andTrichophyton evolceanui which can grow upto 40µg per ml concentration of griseofulvin. (2) Fairly resistant group comprisingMicrosporon cookei, Microsporon vanbreuseghemii, a strain ofMicrosporon gypseum andTrichophyton sp., with growth occurring upto 8–16µg per ml concentration. (3) Sensitive group includes species ofTrichophyton, Keratinophyton, Microsporon, Nannizzia, Chrysosporium andCtenomyces which are completely inhibited at 4–8µg or lower griseofulvin concentrations. Griseofulvin inhibited formation of cleistothecia inK. terreum, delayed pleomorphic growth inT. indicum andN. incurvata, and influenced pigment production in several strains.  相似文献   

7.
Some new taxa of cheirurid trilobites are described from the Lower Palaeozoic of Bohemia and Portugal (see the names in the introduction). The cephala and pygidia of the species C. (Crotalocephalina)gibba gibba, C. (C.)globifrons and C. (C.)pauper have been determined. The speciesEccoptochiloides tumescens andE. scuticauda have been proved to be conspecific.  相似文献   

8.
Soil collected from 54 areas in and around Bogota, Colombia were examined for the presence of keratinophilic fungi by theVanbreuseghem's hair baiting technique. The organisms isolated and frequency are indicated:Trichophyton terrestre, 33;T. ajelloi, 32;Chrysosporium keratinophilum, 30;Microsporon gypseum, 14; andM. fulvum, 1. The perfect stage,Nannizzia gypsea, 1; andArthroderma quadrifidum, 2; were observed growing on hair in three plates.The following organisms apparently have been reported for the first time from soil samples in Colombia:M. fulvum, T. ajelloi, T. terrestre, C. keratinophilum, N. gypsea, andA. quadrifidum.  相似文献   

9.
Alexandre Salino 《Brittonia》2002,54(4):331-339
Three new species ofThelypteris are described and illustrated:T. littoralis andT. paranaensis, endemic to the rainforest of the southern Brazilian Atlantic coast, andT. multigemmifera, endemic to inland gallery forests of the São Paulo state. In addition, four new combinations are made:T. cutiataensis (Brade) Salino,T. iguapensis (C. Chr.) Salino. A new name is proposed forDryopteris lugubris var.quadrangularis:T. montana Salino. The species treated here belong toThelypteris subg.Goniopteris due to the indument of furcate and stellate trichomes.  相似文献   

10.
The effect of different prey mite species on development of the immature stages and on survival and oviposition of adult predator femalePhytoseiulus longipes Evans was studied.P. longipes completed its development onTetranychus pacificus McGregor,Oligonychus punicae (Hirst), andPanonychus citri (McGregor), but not onPetrobia harti (Ewing). Females oviposited while feeding onT. pacificus andO. punicae, but not onP. citri orP. harti. The highest percent survival was observed onT. pacificus, followed byO. punicae andP. citri. The longevity ofP. longipes onP. harti (vial arenas) and on pollen (leaf arenas) was the same as that on leaves with no food. The provision of 10% sucrose solution and clover honey doubled the longevity ofP. longipes females compared with no food.  相似文献   

11.
F. Herard  G. Mercadier 《BioControl》1996,41(2):183-210
Ips acuminatus (Gyllenhall) andTomicus piniperda (L.) were the main scolytid beetles in Scots pine,Pinus sylvestris L., outbreak areas near Orléans, France during 1978-1979.Ips acuminatus attacked thin-bark logs whileT. piniperda attacked thick-bark logs. More than 150 species of insects were associated with these scolytids. Forty-five species (31 predators and 14 parasitoids) were confirmed as natural enemies of bark beetles. Three predators were abundant:Thanasimus formicarius L. (Col.: Cleridae),Rhizophagus depressus (F.) (Col.: Rhizophagidae) andMedetera spp. (Dipt.: Dolichopodidae). The first two were especially frequent in galleries ofT. piniperda, whileMedetera spp. were more abundant in galleries ofI. acuminatus. The main parasitoids wereRhopalicus tutela (Walker) andR. brevicornis Thomson (Hym.: Pteromalidae),Coeloides abdominalis Zetterstedt andC. melanostigma Strand,Dendrosoter middendorfi Ratzeburg andD. hartigii Ratzeburg, andSpathius rubidus Rossi (Hym.: Braconidae). These parasitoids are polyphagous. However,C. abdominalis was obtained fromT. piniperda but not fromI. acuminatus, while 5.rubidus andD. hartigii were obtained fromI. acuminatus but not fromT. piniperda. Temporal and relative abundance of natural enemies ofT. piniperda andI. acuminatus were studied. The predatorsR. depressus andT. formicarius had complementary limiting effects on bark beetles as adults and larvae ofR. depressus fed mainly on scolytid eggs, whileT. formicarius adults attacked scolytid adults and the clerid larvae preyed upon scolytid larvae. The predatory pressure applied byT. formicarius andR. depressus toT. piniperda early during the spring was later complemented by a series of parasitoids and other predators. This sequential timing of the natural enemies ofT. piniperda suggests that the interactions among the guild are more complementary than adverse. Differential timing of the natural enemies in logs infested byI. acuminatus and some evidence of competition between the predatorsMedetera spp. and parasitoids suggested a less effective control of this scolytid. Number and duration of larval instars were determined, and measurements of predatory activity were made forThanasimus formicarius, Rhizophagus depressus,Hypophloeus fraxini Kugelann (Col.: Tenebrionidae),Platysoma frontale Paykull (Col.: Histeridae), andXylocoris cursitans (Fallen) (Het.: Anthocoridae). Predatory activity was evaluated for last instar larvae and adults ofScoloposcelis obscurella (Zetterstedt) (Het.: Anthocoridae), and for last instar larvae ofMedetera sp. andLonchaea collini Hackman (Dipt.: Lonchaeidae)  相似文献   

12.
13.
Thermophilic actinomycetes were isolated from 163 (48.95%) of 333 samples of vegetable substrates and soil from different sites in Anambra and Enugu States in Nigeria.Thermoactinomyces (Tha.) vulgaris was the most common, occurring in 32.4% of samples whileTha. thalpophilus was isolated from 20.1%.Tha. sacchari, Saccharomonospora (Sam.) viridis andSaccharopolyspora (Sap.) rectivirgula were isolated from 3–10.5% of the samples examined.Streptomyces (Stm.) thermovulgaris occurred in 2.7% andThermomonospora spp. in 0.6% of samples. Except forStm. thermovulgaris and, perhaps,Thermomonospora spp., all the species isolated are known to be allergenic in man. The five known allergenic species were abundant in hay and maize silage.T. vulgaris andT. thalpophilus were also frequently isolated from rice straw.Tha. vulgaris, Tha. thalpophilus andSap. rectivirgula were all most numerous in hay whileTha. sacchari was most numerous in maize silage. The widespread occurrence of thermophilic actinomycetes in Nigeria emphasizes the need for investigation of their role in allergic respiratory disorders.  相似文献   

14.
根据福建省南平市峡阳国有林场二代杉木(Cunninghamia lanceolata(Lamb.) Hook)人工林5种采伐剩余物管理措施(收获采伐剩余物和地被层、全树收获、仅收获树干和树皮以及加倍采伐剩余物、炼山)下0-40 cm深度土壤全碳、全氮含量15a的监测数据,研究了采伐剩余物管理措施对杉木林土壤碳氮含量的影响.结果显示,加倍采伐剩余物处理样地5次取样年份(造林第3年、第6年、第9年、第12年和第15年)0-10 cm土层土壤全碳、全氮含量均高于其他处理样地,但单因素方差分析显示,采伐剩余物管理措施在5次取样年份对0-10 cm、10-20 cm和20-40 cm土层全碳、全氮含量均没有显著影响(P>0.05).重复测量方差分析显示,杉木造林15a期间土壤全碳、全氮含量随年份显著变化(P<0.01),但处理措施以及处理措施与取样年份的交互作用对3个土层土壤全碳、全氮含量影响不显著(P>0.05).杉木林15年生时,不同处理样地3个土层碳储量差异不显著(P>0.05),0-40 cm土层平均值为88.71 Mg/hm2.表明采伐剩余物管理措施对亚热带杉木人工林土壤全碳、全氮含量的长期效应并不显著.  相似文献   

15.
Summary A total of 202 soil samples from areas around the cities of Belo Horizonte, Santos, São Paulo, Piracicaba and Itatiaia park were examined by various techniques for the presence of fungi that may be pathogenic to humans and animals.The fungi isolated were:Microsporon gypseum (40),M. cookei (2),Keratinomyces ajelloi (2),T. mentagrophytes (9),T. terrestre (49),T. verrucosum (2),Allescheria boydii (1),Aspergillus fumigatus (2),Candida albicans (21),Cryptococcus neoformans (4), andSporotrichum schenckii (4).Many of the pathogenic fungi were found in habitats where they might be expected to occur in relation to activities of humans and animals.The probable basis for the apparent absence ofParacoccidioides brasiliensis from soil samples was discussed.The following organisms have apparently been reported for the first time from soil samples in Brasil;T. mentagrophytes, T. terrestre, T. verrucosum, A. fumigatus, C. albicans, andS. schenckii.This investigation was supported in whole by Public Health Service Research Grant Number A1-03460, from the National Institute of Allergy and Infectious diseases.  相似文献   

16.
The life history ofSmicronyx guineanus andSm. umbrinus, weevils attackingStriga hermonthica, was studied in Burkina Faso, West Africa. Field experiments were conducted in 1992 and 1993 at Kaya, in fields of sorghum (Sorghum bicolor (L.) Moench and pearl millet (Pennisetum americanum (L.) K. Schum. (syn.P. typhoides (Burm.) Stapf &; Hubb). The weevils are univoltine; the adults emerge in late August, mate and eggs are laid in the ovary ofStriga inflorescence. Larval feeding in the ovary causes galling and prevents seed production. The main damage toStriga seed capsule is caused by the larvae of at least twoSmicronyx species. Last-instar larvae drop to the soil and bury themselves to a depth of 1–15 cm, pupate and enter into dormancy. Most pupae are found in the upper 5–10 cm of the soil. The pupal period lasts from late October to late July. In May, we found 75.6% of pupae against 24.4% of adults in dormancy.  相似文献   

17.
R. J. Milner 《BioControl》1973,18(4):383-390
A dose-mortality technique was used to compare the pathogenicity ofNosema whitei for 4 stored products pests.Tribolium castaneum, T. confusum andOryzaephilus surinamensis were similar in susceptibility, whileT. anaphe was at least 100 times more susceptible. A possible explanation for this difference is thatT. anaphe has a much longer developmental time (28 days at 25°C) than the other 3 species (20 days at 25°C). The host range was studied in another 8 species from 2 orders.T. brevicornis, T. destructor, andT. madens were all susceptible while the other species tested (includingTenebrio molitor, Palorus ratzburgi andPlodia interpunctella) were refractile to infection.  相似文献   

18.
E. Tremblay 《BioControl》1984,29(2):203-209
The parasitoid complex of the Black Citrus Aphid,Toxoptera aurantii (B.d.F.) in the Mediterranean area has been complemented on the basis of samples collected in South Italy and Lebanon. To the complex presently belong 10 Ichneumonoid species of the generaAphidius Nees,Diaeretiella Staryý,Ephedrus Haliday,Lipolexis Förster,Lysiphlebus Förster,Praon Haliday andTrioxys Haliday. Of these,Aphidius colemani Viereck, in spite of its wide distribution in the Mediterranean region, seems to be restricted to Near East (Israel and Lebanon) asT. aurantii parasitoid. The nearctic speicesLysiphlebus testaceipes (Cresson) is localized in Spain, South France, Corsica, Central and South Italy, including Sicily. In Italy, this endoparasitoid has heavily interfered with the local dominant congeneric speciesLysiphlebus confusus Tremblay & Eady andLysiphlebus fabarum (Marshall). The possible associative relationships betweenLysiphlebus testaceipes andL. fabarum have been examined in the samples collected in South Italy. The results of the examination suggest that the 2 species are negatively associated with each other, i.e. the abundance of 1 of the 2 species makes it more likely that the other will decrease in numbers. Moreover, the data concerning the relative abundance of both species in the same area indicate that a shift may have occurred in favour ofL. testaceipes between 1977 and 1978. The nearctic parasitoid seems to be able to displace the 2 congeneric species by a competitive biological mechanism which is still in course of investigation.  相似文献   

19.
Y. Hironori  S. Katsuhiro 《BioControl》1997,42(1-2):153-163
Life tables for two predatory ladybirds,Coccinella septempunctata andHarmonia axyridis, were constructed in two years in which prey abundance differed. The prey aphid,Aphis gossypii, was abundant on its primary host from late May to late June. Females ofH. axyridis andC. septempumctata laid their eggs during the increase and peak in aphid abundance. The oviposition period ofC. septempunctata started before and was shorter than that ofH. axyridis. In both species, intraguild predation and/or cannibalism of the egg and fourth instar stages, but rarely of other developmental stages, were observed. Fourth instar larvae ofH. axyridis had to complete their development when aphids were scarce more frequently than those ofC. septempunctata. The highest frequency of intra- and interspecific predation was of fourth instarH. axyridis larvae. In terms of intraguild predation, the larvae ofH. axyridis preyed on larvae ofC. septempunctata, but the reverse was not observed. Percentage survival from egg to adult inH. axyridis was higher than inC. septempunctata in both years, and least in both species in the year of low aphid abundance. These results suggest that prey abundance influenced the frequency of cannibalism and intraguild predation, which were important in structuring this guild of ladybirds.  相似文献   

20.
Here 13 species of the nonfoliicolous species of the lichen familyEctolechiaceae Zahlbr. em.Haf. are reported, which were found in a collection from Brazil. Six species are described as new:Badimia corticola (sp.n.),Calopadia isidiosa (sp.n.),C. psoromoides (sp.n.),C. subfusca (sp.n.),Tapellaria corticola (sp.n.), andT. schindleri (sp.n.). Seven species have been identified with earlier described species:Calopadia chacoënsis (Malme) comb. n. (=Lopadium chacoënse Malme),C. foliicola (Fée) Vězda,C. fusca (Müll. Arg.) Vězda,C. lecanorella (Nyl.) comb. n.,C. perpallida (Nyl.) Věda,C. phyllogena (Müll. Arg.) Vězda, andTapellaria epiphylla (Müll. Arg.) Sant. A key and illustrations for all studied species are provided, and the nomenclatural problem of the correct generic name of thePyrenotrichum Mont. (anamorph) forCalopadia Vězda orTapellaria Sant. (teleomorphs) are discussed.  相似文献   

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