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1.
Five isolates of a species of Colletotrichum were collected from Japanese barnyard millet (Echinochloa utilis) in Japan. Although the fungus had once been identi-fied as C. graminicola sensu lato, it was clearly different from C. graminicola isolated from maize (Zea mays) in its falcate and short conidia, 18.0–22.2 μm in length, cultural characteristics, and specific pathogenicity to E. utilis. Moreover, molecular phylogenetic analyses using sequences of rDNA-ITS, HMG, and SOD2 indicated a monophyly of the isolates. A new species, Colletotrichum echinochloae, is then proposed based on the morphological, pathological, and molecular characteristics.  相似文献   

2.
Ascomata of a powdery mildew-like fungus have been found on Carpinus laxiflora in Tochigi Prefecture of Japan since 2003. The morphological and molecular characteristics of this fungus are reported, and a new species, Erysiphe fimbriata, is proposed. It has large chasmothecia (200–250 μm in diameter) with long (up to 4–5 mm in length), fimbriate appendages arising from the upper half of the chasmothecia and turning upward, and numerous asci (22–38 per chasmothecium). Erysiphe fimbriata is a unique fungus both genetically and morphologically.  相似文献   

3.
A survey for entomopathogenic fungi of Musca domestica adults was conducted in poultry houses in La Plata, Buenos Aires province, Argentina, during the years 2002 and 2003. Adult house flies were found infected with the fungus Beauveria bassiana (Bals.) Vuill. (Deuteromycotina: Hyphomycetes) from field collections, with a natural infected prevalence between 0.4–1.45%. This is the first record of natural infections of house flies caused by B. bassiana for the neotropics. Pathogenicity assays under laboratory conditions showed 94% adult mortality at 14 days post challenge. CIC fellow  相似文献   

4.
Circa 1900, a farmer from the eastern US planted 11 American chestnut (Castanea dentata) seeds on a newly established farm near West Salem in western Wisconsin. These trees were very successful, producing a large stand of over 6,000 trees. Since this area is well outside the natural range of chestnut, these trees remained free from chestnut blight until 1987. In the West Salem stand, chestnuts are the dominant species of a mixed forest community, reminiscent of the chestnut–oak ecosystems of pre-1900 Appalachia. To identify putative mycorrhizal associates of chestnut in this unique forest, our approach was twofold: (1) an extensive fruiting body survey was conducted for four seasons that yielded approximately 100 putative mycorrhizal species and (2) a belowground molecular approach was used to generate DNA sequences of the internal transcribed spacer region from ectomycorrhizae. Unexpectedly, chestnut did not appear to be the dominant underground ectomycorrhizal-forming plant species. This study highlights the need to identify the plant host species when conducting belowground molecular-based surveys and provides preliminary identification of ectomycorrhizal fungi associated with a disjunct stand of American chestnut. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

5.
A new species from the Bolivian highlands is described as Elaphoglossum cristatum. It is very similar to E. engelii but is characterized by a (for subsect. Muscosa unique) cristate perispore structure with irregular deposits (versus papillate spores), more densely ciliate petiole scales (50–80 versus 10–30 cilia per scale), somewhat thicker blade texture, denser scale cover, and paler, more reddish rhizome scales.  相似文献   

6.
The metabolites of endophytic fungus Penicillium sp. from the leaf of Hopea hainanensis were reported for the first time. By bioassay-guided fractionation, the EtOAc extract of a solid-matrix steady culture of this fungus afforded six compounds, which were identified through a combination of spectral and chemical methods (IR, MS, 1H- and 13C-NMR) to be monomethylsulochrin (1), rhizoctonic acid (2), asperfumoid (3), physcion (4), 7,8-dimethyl-iso-alloxazine (5) and 3,5-dichloro-p-anisic acid (6). Compounds 2, 3 and 6 were obtained from Penicillium sp. for the first time. All of the six isolates were subjected to in vitro bioactive assays including antifungal action against three human pathogenic fungi Candida albicans, Trichophyton rubrum and Aspergillus niger and cytotoxic activity against the human nasopharyngeal epidermoid tumor KB cell line and human liver cancer HepG2 cell line. As a result, compounds 24 and 6 inhibited the growth of C. albicans with MICs of 40.0, 20.0, 50.0 and 15.0 μg/ml, respectively and the compound 6 showed growth inhibition against A. niger with MICs of 40.0 μg/ml. In addition, compounds 13 and 6 exhibited cytotoxic activity against KB cell line with IC50 value of 30.0, 20.0, 20.0, 5.0 μg/ml, respectively and against HepG2 cell line with IC50 value of 30.0, 25.0, 15.0, 10.0 μg/ml, respectively.  相似文献   

7.
Beata Zimowska 《Biologia》2010,65(4):603-608
In the years 2004–2006 the species P. sclareae was isolated from sage stems showing the symptoms in the form of bark peeling off and breaking. On the basis of 5 isolates randomly chosen from the fungus population, morphology and the conditions of temperatures favourable for the most intensive growth and creation of the fungus infectious material were studied. The temperature of −6°C was viewed as unfavourable for the fungus growth, and that of 32°C was considered to prevent the formation of picnidia and conidia. The dynamic growth of the colonies and the formation of numerous picnidia and conidia were observed at the temperatures ranging from 20°C to 28°C.  相似文献   

8.
Symptoms of fairy rings caused by Lepista sordida have been reported on Zoysiagrass (Zoysia spp.) turf maintained at fairway height (2 cm), but not on bentgrass (Agrostis spp.) maintained at putting green height (0.5 cm). The mycelia of this fungus inhabit primarily the upper 0–2 cm layer of the soil extending into the thatch. To compare conditions for the mycelial growth in Z. matrella turf to those in A. palustris turf, we examined the effects of nutrients, temperature, water potential, and pH in the field as well as in the laboratory. Greater growth of the mycelia was observed in medium that included hot water extracts from soil of the 0–1 cm zone in Z. matrella turf compared to that from A. palustris. The upper soil layer in Z. matrella turf contained more organic matter from clippings than that in A. palustris. The temperature and water potential of the 0–2 cm soil zone in Z. matrella turf were also more favorable for the mycelial growth. The soil pH values of this zone in Z. matrella turf were less favorable compared to A. palustris but within the range for accelerating mycelial growth. Part of this study was presented orally at the 46th meeting of the Mycological Society of Japan in 2002  相似文献   

9.
 A marine fungus was isolated from the black tiger prawn Penaeus monodon at Nha Trang, Vietnam, on March 20, 2001 and named isolate NJM 0131. The fungus was identified as Haliphthoros milfordensis from the characteristics of asexual reproduction, and its physiological characteristics were investigated. Although the optimum temperature for growth of the isolate was 25°–30°C, the fungus grew at a wide range of temperatures (15°–40°C). H. milfordensis grew well in 50%–100% seawater, but poorly in PYG agar containing 1.0%–5.0% NaCl and KCl. The fungus grew at a wide range of pH (4.0–11.0) with the optimum pH value of 7.0–9.0. The isolate also showed pathogenicity to swimming crab larvae (Portunus trituberculatus) by artificial infection, but mortality was not high. This is the first report of disease in the black tiger prawn P. monodon in Vietnam caused by H. milfordensis. Received: July 22, 2002 / Accepted: January 21, 2003 Correspondence to:K. Hatai  相似文献   

10.
Eastern cottontail (Sylvilagus floridanus, fam. Leporidae), introduced into Piedmont (Italy) in the 1960s, was studied as carrier of dermatophyte fungi. Of 216 hair samples collected from animals culled between September 1999 and July 2000 in the Province of Alessandria (Piedmont, Italy) during a pest control project, 57 (26.4%) yielded dermatophyte colonies. As two different species of dermatophytes grew from two samples, a total of 59 fungal isolates (26.5%) were obtained. Six dermatophyte species both geophilic (M. gypseum, M. cookei, Trichophyton ajelloi, T. terrestre) and zoophilic (M. canis, T. mentagrophytes) were identified. No sex-related differences were found but season-related differences were observed. The highest prevalence of dermatophyte-positive samples was recorded in May–September, due to the geophilic fungi whose prevalence decreased during colder and increased during warmer months ( p < 0.001). The presence of zoophilic dermatophytes, T. mentagrophytes, commonly associated with rodents, small mammals and lagomorphs and M. canis, usually correlated with domestic environment, did not change the whole year round. As Eastern cottontail has been showed to be a carrier of dermatophytes transmissible to man (M. canis, T. mentagrophytes and M. gypseum), it may represent a source of infection for gamekeepers, hunters and veterinarians.  相似文献   

11.
Summary This study reports a protocol for successful micropropagation of Decalepis arayalpathra (Joseph and Chandras) Venter. (Janakia arayalpathra Joseph and Chandrasekhran; Periplocaceae), a critically endangered and endemic ethnomedicinal plant in the southern forests of the Western Ghats which is overexploited for its tuberous medicinal roots by the local Kani tribes. Natural regeneration is rare and conventional propagation is difficult. Conservation of the species through micropropagation was attempted. The nodal explants of greenhouse-raised plants, were more desirable than cotyledonary nodal explants of aseptic seedlings. The basal nodes (73%) of 12–16-wk-old greenhouse-grown plants cultured in Murashige and Skoog (MS) medium containing 12.96 μM 6-benzyladenine (BA), 2.48 μM 2-isopentenyladenine (2-ip) and 2.68 μM α-naphthaleneacetic acid (NAA) formed 16–17 cm long unbranched robust solitary shoots in 8 wk. Cotyledonary nodal explants cultured in the same medium showed multiple shoot formation and axillary branching. But the shoots were thin, fragile and not suitable for mass propagation. Single nodes of a solitary shoot subcultured on MS medium containing 2.22 μM BA and 0.24 μM 2-ip together produced 9.8±0.3 nodes from 18.0±0.6 cm long shoots within 5–6 wk. The basal nodes of the shoots so formed were repeatedly subcultured to increase the stock of propagules while the 2.5–3.0 cm terminal cuttings were used for rooting. The best root induction (68%) and survival (86%) was achieved on half-strength MS medium supplemented with 1.07 μM NAA. Field-established plants showed uniform growth and phenotypic similarity to parental stock.  相似文献   

12.
A new Dactylella species, Dactylella alba was isolated from the ascospores of Orbilia alba collected in Wenshan County, Yunnan Province, China. Conidiophores were either not branched or occasionally branched, bearing divergent sterigmata on the tip with single conidium on each. Conidia were elongated ellipsoids, 1–2 septate, mostly 1 septate. By combining the ITS sequence with morphological characteristics, a new anamorphic species is described and illustrated together with its teleomorph.  相似文献   

13.
14.
Two extracellular chitinases were purified from Paecilomyces variotii DG-3, a chitinase producer and a nematode egg-parasitic fungus, to homogeneity by DEAE Sephadex A-50 and Sephadex G-100 chromatography. The purified enzymes were a monomer with an apparent molecular mass of 32 kDa (Chi32) and 46 kDa (Chi46), respectively, and showed chitinase activity bands with 0.01% glycol chitin as a substrate after SDS-PAGE. The first 20 and 15 N-terminal amino acid sequences of Chi32 and Chi46 were determined to be Asp-Pro-Typ-Gln-Thr-Asn-Val-Val-Tyr-Thr-Gly-Gln-Asp-Phe-Val-Ser-Pro-Asp-Leu-Phe and Asp-Ala-X-X-Tyr-Arg-Ser-Val-Ala-Tyr-Phe-Val-Asn-Trp-Ala, respectively. Optimal temperature and pH of the Chi32 and Chi46 were found to be both 60°C, and 2.5 and 3.0, respectively. Chi32 was almost inhibited by metal ions Ag+ and Hg2+ while Chi46 by Hg2+ and Pb2+ at a 10 mM concentration but both enzymes were enhanced by 1 mM concentration of Co2+. On analyzing the hydrolyzates of chitin oligomers [(GlcNAc) n , n = 2–6)], it was considered that Chi32 degraded chitin oligomers as an exo-type chitinase while Chi46 as an endo-type chitinase.  相似文献   

15.
Summary We describe an in vitro propagation protocol for Zingiber petiolatum (Holttum), I. Theilade, a rare species from the southern part of Thailand. Fruits were surface-sterilized and seeds germinated on Murashige and Skoog medium (MS) medium supplemented with 3% sucrose. Three-month-old seedlings were used as initial plant material for in vitro propagation. Terminal buds of the plants were inoculated on MS medium containing 6-benzylaminopurine (BA; 2.2–35.5 μM) alone or in combination with 1-naphthaleneacetic acid (0.5 μM). Eight weeks after inoculation, the cultures were transferred to MS medium without plant growth regulators for 4wk. The cultures transferred from MS medium with 17.8 μM BA revealed the highest shoot induction rate of 6.1±0.7 shoots per explant. Rooting was spontaneously achieved in MS medium without plant growth regulators. Rooted plants were successfully transplanted to soil.  相似文献   

16.
A new species of Hirsutella, H. proturicola, isolated from a subterranean proturan (Baculentulus densus; Protura, Hexapoda), is described and illustrated. Hirsutella proturicola is characterized by producing monoblastic phialides of 24–51.5 × 2.5–5 μm with a slightly roughened neck, fusiform and curved conidia of 9–18 × 2.5–4 μm that have a truncate base and a papillate projection often capped with sheath-like mucilage, and pluricellular, globose to subglobose chlamydospores of 21–48 × 21–41.5 μm. This species is morphologically and phylogenetically close to H. rostrata, an acaropathogenic species, but can be distinguished from the size of the phialides and the size and shape of the conidia.  相似文献   

17.
Caprella mutica Schurin is an epifaunal amphipod crustacean which originates in north-east Asia and has spread throughout the world, yet very little is known about fundamental aspects of this species biology. This paper examined the survivorship of C. mutica reared under laboratory conditions at 13–14 °C, 14 h light: 10 h dark photoperiod and fed commercial salmon feed, the diatom Cylindrotheca fusiformis Reumann and Lewin, the macroalgae, Fucus vesiculosus L. and given no additional feed. In addition, growth, maturation and reproduction of C. mutica fed C. fusiformis were assessed. No significant difference in survivorship of C. mutica was observed for the diet types over the experimental period. C. mutica was able to survive for upto 20 days without additional food. Average survival time of males and females fed the diatom, C. fusiformis was 68.8 d (range = 62–73 d) and 82.0 d (range = 76–92 d). Juvenile C. mutica emerged from the brood pouch at a body length of 1.33 mm and moulted at 5.0–11.0 day intervals. Males exhibited faster growth rates than females after Instar VII. Females produced their first brood at Instar VII, 24–26 days post-hatching and with an average body length of 8.5 mm. Each female had an average of two broods sequentially and these were released at 20.2 day intervals. Brood size for a single female increased from 11.3 (±9.9) hatchlings at Instar VII to 25.5 (±11.5) at Instar IX and the maximum number of hatchlings produced by a single female was 82. The results suggest that C. mutica exhibits a number of life-history traits that would potentially enable it to withstand global transportation and to rapidly become established in an introduced region, if environmental conditions are suitable.  相似文献   

18.
A mycelial formulation of the fungus Myrothecium verrucaria (IMI 361690) containing 0.20% Silwet L-77 surfactant was found to be highly efficacious in controlling the exotic invasive weed kudzu. The mycelium can be rapidly (48–72 h) produced in several media, including an inexpensive soy flour–corn meal medium. Mycelial yields were 2, 10, and 25 g dry weight l−1 in Czapek-Dox, Richard’s V-8, and soy flour–corn meal media, respectively. Scale-up production in soy flour–corn meal medium using laboratory fermenters (10–25 l), resulted in a mycelial formulation that caused 90% mortality of naturally-occurring mature (0.9–1.0 m in height) kudzu within 48 h after application in field experiments. HPLC analyses revealed that the mycelium produced in this liquid culture contained no detectable amounts of the trichothecene mycotoxins roridin A and verrucarin A (limit of detection 2 μg ml−1). This has resulted in a safer, yet effective bioherbicidal product. We anticipate that these findings should improve the probability of EPA registration and subsequent commercial development of this bioherbicide.  相似文献   

19.
To investigate the life history and ecology of the mudskipper Periophthalmus magnuspinnatus, observations and collection were made on coastal mudflats in southern Korea. Periophthalmus magnuspinnatus was active from May to September on the mudflats, exclusively occupying rough and elevated or sloped mudflats of the seashore or the stream mouth, usually vegetated with halophilous grasses. The congeneric species, P. modestus, mainly occurred on extensive low-elevation and level mudflats with no visible vegetation. An apparent alternation of habitat use by P. modestus took place on mudflats at the stream mouth in mid-October, when P. magnuspinnatus began wintering in its burrow and P. modestus came onto the vacated mudflats to construct burrows for wintering. The active season for P. magnuspinnatus at 17°C or higher air temperature was a little shorter than that of P. modestus. Periophthalmus magnuspinnatus constructed a burrow for the entire season in the highest area of the intertidal mudflat, where they hid themselves during high tide or when frightened, whereas P. modestus were likely to use any burrow constructed by other animals or sunken places to hide. The main stomach contents of P. magnuspinnatus were crabs and gammarids. During the reproductive season from May to July, P. magnuspinnatus performed mating behaviors and constructed a spawning burrow similar to the ones known for P. modestus, except their body color turned dark and quivering body movements were observed in the mature male instead of a pink or orange body color and wiggling body movements as in P. modestus. Eggs, measuring 1.56–1.69 mm in major axis and 0.94–1.0 mm in minor axis, were laid on the ceiling and the side wall of the “J”-shaped spawning room generally known for Periophthalmus species. Young of both species started to occur on the mudflat in June.  相似文献   

20.
Early life stages of Artedidraco skottsbergi and A. shackletoni were collected off Adélie Land. The morphology and pigmentation pattern of nine larvae and juveniles of A. skottsbergi between 17.2 and 21.4 mm in standard length (SL), and of two juveniles of A. shackletoni measuring 25.1 mm SL were described. A. skottsbergi was characterized by a heavily pigmented body, except for the caudal peduncle, with distinctively dense pigmentation on the ventrolateral half of the body and caudal section (17.2–17.9 mm SL). Furthermore, they had no pigmentation on the pectoral fin base until they attained 21.4 mm SL. Juvenile A. shackletoni had a heavily pigmented body except for the ventral side of the abdomen and the anal fin base. The proximal part of the dorsal fin and most of the anal fin were covered with melanophores. Although knowledge of larval and juvenile Artedidraco species is limited, the distribution of melanophores on the fins, pectoral fin base and caudal peduncle at each developmental stage may be useful for species identification.  相似文献   

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