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1.
The potential of the eulophid parasitoid Phymastichus coffea LaSalle to control coffee berry borer Hypothenemus hampei (Ferrari) populations under field conditions in Colombia was evaluated. Parasitoid adults were released one, five and nine days after artificial infestations of 90-, 150- and 210-day-old coffee berries with H. hampei females. The position of the beetle inside the berry and the parasitism levels were assessed ten days after each P. coffea release. Parasitism of H. hampei by P. coffea was significantly affected by the age of the berries at the time of infestation, and by the position of the beetle inside the berries. Highest levels of parasitism were recorded in 150-day-old berries (75-85%) and in 90-day-old berries (75%) when P. coffea were released one day after the artificial infestation with H. hampei. In 150-day-old berries, highest levels of parasitism were recorded for H. hampei found in the outer layer of the endosperm followed by beetles penetrating the exocarp. Increasing the time of P. coffea releases after the artificial infestations with H. hampei led to decreased levels of parasitism in beetles attacking 90- and 150-day-old coffee berries. Low levels of parasitism were recorded in H. hampei females infesting older coffee berries because most of the beetles had already constructed galleries deep in the endosperm of the berries, i.e. out of reach of the parasitoid. The potential of P. coffea for biological control of coffee berry borer in Colombia is discussed.  相似文献   

2.
Adults of Cephalonomia stephanoderis Betrem were detected (in November 2003) during the sampling of Coffea canephora Pierre ex A. Froehner berries damaged by Hypothenemus hampei Ferrari (Coleoptera: Scolytidae) in Ouro Preto D'Oeste - Rond?nia, Brazil (10 degrees 45'S and 62 degrees 15'W). From January to July 2004, the parasitoid was monthly sampled in 200 berries damaged by H. hampei. Probably, C. stephanoderis can already exert some parasitism pressure at the coffee berry borer population. The occurrence of this parasitoid in natural conditions points out to another alternative for the biological control of the H. hampei in Rond?nia. This is the first record of C. stephanoderis in coffee plantations of the Brazilian Amazonia.  相似文献   

3.
The most abundant marine fungi encountered in various regions of the Sea of Japan belong to the genera Penicillium, Aspergillus, Wardomyces, Trichoderma, Chrysosporium, and Chaetomium. Facultative marine fungi of the genera Scytalidium, Verticillium, and Oidiodendron and obligate marine fungi of the genus Dendryphiella are much less abundant. The composition of marine sediments and the anthropogenic load on them were found to influence the abundance and species diversity of fungi, as well as the occurrence of fungal strains producing hemolytically active substances. The biodiversity of mycobiota and the abundance of hemotoxin-producing fungi in marine sediments may be used to evaluate the anthropogenic load on marine biocenoses. Hemolytic compounds were produced by 57% of the fungi isolated from marine sediments. The hemolytic activity of Chaetomium spiculipilium was revealed in the fraction of the culture liquid containing extracellular fatty acids and pigments. The fatty acid composition of this marine fungus was determined.  相似文献   

4.
The currently existing sample procedures available for decision-making regarding the control of the coffee berry borer Hypothenemus hampei (Ferrari) (Coleoptera: Curculionidae: Scolytinae) are time-consuming, expensive, and difficult to perform, compromising their adoption. In addition, the damage functions incorporated in such decision levels only consider the quantitative losses, while dismissing the qualitative losses. Traps containing ethanol, methanol, and benzaldehyde may allow cheap and easy decision-making. Our objective was to determine the economic injury level (EIL) for the adults of the coffee berry borer by using attractant-baited traps. We considered both qualitative and quantitative losses caused by the coffee borer in estimating the EILs. These EILs were determined for conventional and organic coffee under high and average plant yield. When the quantitative losses caused by H. hampei were considered alone, the EILs ranged from 7.9 to 23.7% of bored berries for high and average-yield conventional crops, respectively. For high and average-yield organic coffee the ELs varied from 24.4 to 47.6% of bored berries, respectively. When qualitative and quantitative losses caused by the pest were considered together, the EIL was 4.3% of bored berries for both conventional and organic coffee. The EILs for H. hampei associated to the coffee plants in the flowering, pinhead fruit, and ripening fruit stages were 426, 85, and 28 adults per attractive trap, respectively.  相似文献   

5.
Falling of berries bored by Hypothenemus hampei (Ferrari) may be the major loosing factor during the fruiting period. However, only those bored berries which remain in the soil surface before a new yielding period have been recognized as responsible for the damage level Ho achieved by new developing berries. In this paper, we investigated in the plants and in the soil surface, the presence of Coffea canephora cv. Conilon berries bored by H. hampei during the yielding period in Ouro Preto d'Oeste, Rond?nia, Brazil. We took samples, weekly, from December 2000 to June 2001. The data were submitted to the Surviving Regression Analysis, based on a censored Weibull model. During the yielding period, berries fall down continuously and, in average, the proportion of H. hampei bored berries was 4 to 20 times higher in the soil (P < 2,3 x 10-18, n = 62,747) than in the plants. Thus, we argue that adding the "soil environment" to the integrated management strategies could point to new technologies for the control of this insect.  相似文献   

6.
AIMS: To examine how UVC affects the different genera of fungi commonly isolated from grapes, with the aim of understanding changes in mycobiota during grape ripening and possible applications for preventing grape decay during storage. METHODS AND RESULTS: Spores of Aspergillus carbonarius, Aspergillus niger, Cladosporium herbarum, Penicillium janthinellum and Alternaria alternata (between 100-250 spores/plate agar) were UVC irradiated for 0 (control), 10, 20, 30, 60, 300 and 600 s. Plates were incubated at 25 degrees C and colonies were counted daily up to 7 days. Alternaria alternata and Aspergillus carbonarius were the most resistant fungi. Conidial germination in these species was reduced by approx. 25% after 10 s of exposure, compared with greater than 70% reduction for the remaining species tested. Penicillium janthinellum spores were the most susceptible at this wavelength. UVC exposures of 300 s prevented growth of all isolates studied, except for Alternaria alternata. CONCLUSIONS: UVC irradiation plays a major role in selecting for particular fungi that dominate the mycobiota of drying grapes. SIGNIFICANCE AND IMPACT OF THE STUDY: The UVC irradiation of harvested grapes could prevent germination of contaminant fungi during storage or further dehydration.  相似文献   

7.
There were 1762 fungi isolated from the atmosphere of Trujillo city (Peru) during the year 1971. These isolants belonged to 23 genera of fungi. The most frequently isolated were: Cladosporium, Penicillium, Fusarium, Stemphylium, Alternaria, Helminthosporium, Aspergillus and Tilachlidium. Nine genera are reported for first time from the air of the city (Tilachlidium, Cephalosporium, Mucor, Aureobasidium, Hormiscium, Trichoderma, Stachybotrys, Paecilomyces and Fisidium). Six genera may be alergenic for asthmatic patients of Trujillo city.  相似文献   

8.
山东省烟草根际土壤真菌多样性研究   总被引:1,自引:1,他引:1  
为了有助于研究烟草根际土壤真菌与根茎病害发生程度的相互关系,文中对采自山东省6个地区的122份烟草根际土壤样品进行了真菌的分离和培养,采用形态学方法进行鉴定,并分析了菌群的多样性组成。从山东烟草根际土壤中分离和鉴定出真菌22属79种,其中接合菌门4属6种,子囊菌门1属1种,无性型真菌17属72种。优势真菌种群为青霉属(Penicillium)、木霉属(Trichoderma)、镰孢菌属(Fusarium)和曲霉属(As-pergillus),所占分离真菌总菌数的比例分别为22.39%、13.62%、12.69%和9.88%。6个采样地区间真菌菌群的多样性水平存在差异,其中诸城地区的多样性指数(H′=2.066 6)、均匀度指数(J=0.689 8)和丰富度指数(R=3.730 1)均最高。  相似文献   

9.
Mansfield MA  Kuldau GA 《Mycologia》2007,99(2):269-278
The mycobiota of fresh and ensiled maize was studied with culturing techniques and a DNA sequence-based approach. Freshly chopped and ensiled maize were collected for 2 y from 12 farms in Pennsylvania. Samples were plated on selective media and isolates identified by morphology and sequences of the internal transcribed spacer regions of rDNA, 800-900 bp of the 5' end of the translation elongation factor 1-alpha gene and a portion of the rodA gene (Aspergillus fumigatus only). ITS regions were amplified from total silage DNA, cloned, sequenced and compared to fungal ITS sequences in GenBank with the BLAST-N algorithm. For samples analyzed by both methods, the molecular technique detected a greater number of species than selective plating. Plating recovered several Penicillium and Fusarium species and Aspergillus fumigatus, while molecular analysis detected Alternaria, Penicillium and Fusarium species. Data from both methods found that Fusarium and Penicillium were the dominant mycotoxigenic fungi in silage, while yeast made up the majority all fungi recovered or detected. Known mycotoxigenic species often accounted for 50% or more of the total number of species isolated or detected at each site. Viable Fusaria were not isolated from or detected in ensiled maize, suggesting that Fusarium species do not survive the ensiling process. Results from this study suggest that given the numerous species of fungi present in silage with mycotoxin producing ability, there is a strong possibility that silage may be contaminated with multiple toxins simultaneously.  相似文献   

10.
Soil mycofloral diversity plays a pivotal role in crop production and is an integral part of any ecosystem. Pigeonpea cropping system provides a congenial environment to soil microbes by fixing nitrogen and solubilizing phosphorus which in turn provides sufficient nutrients for their prolific growth. The present study was undertaken to know the fungal diversity in calcareous soil of Bihar region in India, which are not supportive to growth of many fungi owing to high calcium content. Soil samples were collected from pigeonpea cropping system treated with native and commercial isolates of phosphorus solubilizing bacteria (PSB) and plant growth promoting rhizobacteria (PGPR) along with Rhizobium. Thirty-seven species belonging to seven genera and a group of unidentified species were isolated. Aspergillus and Penicillium were the dominant genera in all the treatments. Absidia and Cunnighmella were distributed only once as rare genera. Though single species of Pythium, Rhizopus, Periconia, Geotrichum and Gliocladium genera were recorded but their occurrence was even in all the treatments. The diversity and equitability index were not varied much in different treatments except one. The deuteromucetous fungi occupied the highest space followed by zygomycetous, mycelia sterilia and mastigomycetous fungi.  相似文献   

11.
Klich  Maren A. 《Mycopathologia》1998,142(2):97-100
Soil is presumed to be a major source of inoculum for Aspergillus flavus which contaminates cottonseed and produces the potent carcinogen, aflatoxin. Little is known about the mycoflora of the low desert soils of cotton fields where aflatoxin is a chronic problem. In this study, soils from cotton fields in southwestern Arizona and southeastern California were assayed for filamentous fungi. Forty-two taxa, predominantly in the genera Aspergillus, Penicillium and Fusarium, were isolated. To determine whether or not compounds produced by these fungi could be potential inhibitors of A. flavus, extracts of strains of each taxon were tested for their ability to inhibit growth of A. flavus. Twelve taxa produced compounds inhibitory to A. flavus, including several strains of Fusarium solani, Penicillium vinaceum and Aspergillus auricomus. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

12.
Previous studies of hypersaline environments have revealed the dominant presence of melanized yeast-like fungi and related Cladosporium spp. In this study, we focused on the genera Aspergillus and Penicillium and their teleomorphic forms. From oligotrophic and eutrophic hypersaline waters around the world, 60 different species were identified, according to their morphological characteristics and extrolite profiles. For the confirmation of five new species, additionally, sequence analysis of the internal transcribed spacer region, the partial large subunit-rDNA and the partial β-tubulin gene was performed. The species Aspergillus niger, Eurotium amstelodami and Penicillium chrysogenum were detected with the highest frequencies at all of the sampled sites; thus, they represent the pan-global stable mycobiota in hypersaline environments. Possible candidates were also Aspergillus sydowii and Eurotium herbariorum, as they were quite evenly distributed among the sampled sites, and Aspergillus candidus, which was abundant, but more locally distributed. These species and their byproducts can accumulate downstream following evaporation of brine, and they can become entrapped in the salt crystals. Consequently, marine salt used for consumption can be a potential source of food-borne fungi and their byproducts. For example, ochratoxin-A-producing species Penicillium nordicum was recovered from brine, salt and salted meat products.  相似文献   

13.
Forty-four fungal species belonging to 20 genera were isolated from 30 samples of qat leaves. The most frequent genera wereAspergillus, Alternaria, Penicillium, andCladosporium followed byFusarium, Drechslera, Chœtomium, andMucor. The most prevalent species in above genera wereAspergillus niger, A. flavus, A fumigatus, Alternaria alternata, Penicillium chrysogenum, P. citrinum, Cladosporium cladosporioides, andFusarium verticillioides. From these fungi, 17 species (39%) related to 7 genera (35%) proved to be true endophytes. Eleven out of 75 isolates were mycotoxigenic.A. alternata produced alternariol and alternariol monomethyl ether whereasA. flavus produced aflatoxins B1 and B2. Ochratoxin A, sterigmatocystin, citrinin and T-2 toxin were produced byA. ochraceus, A. versicolor, P. citrinum andF. oxysporum, respectively. The presence of such toxigenic fungi associated with qat leaves is considered to be a threat to public health.  相似文献   

14.
Fungal pathogens have become a serious threat to wildlife, threatening populations of even once common, abundant species. We describe the mycobiota associated with the nasal hairs of three Molossid bat species, Cynomops planirostris, Molossus molossus, and Molossus rufus, in southwest Brazil. Bats were captured in the Cerrado and Pantanal biomes. We cultured 22 fungal isolates from twelve individual bats. Sixteen sequences of the ITS region were obtained, yielding 11 unique sequence types from the genera Aspergillus, Cladosporium, Paecilomyces, and Penicillium. No obvious detrimental effects on the bats from the fungi were observed, although some species or genera that we identified are known pathogens in other species. This is the first report of such fungi associated with the nasal hairs of Molossid bats. Our results indicate the need for further research on the biodiversity, ecological role, and potential effects of this mycobiota on Molossid bats.  相似文献   

15.
The microbial composition of olive mill wastewater (OMW) from four disposal ponds has been studied. Such OMW samples contained a variable (but high) number of bacteria, yeasts and molds. Among the latest, members of twelve different genera (Acremonium, Alternaria, Aspergillus, Chalara, Fusarium, Lecytophora, Paecilomyces, Penicillium, Phoma, Phycomyces, Rhinocladiella and Scopulariopsis) were found. Members of five genera (Chalara, Fusarium, Paecilomyces, Penicillium and Scopulariopsis) were widely distributed, and they were able to grow efficiently in undiluted OMW as a sole source of nutrients. Strains of Fusarium, Paecilomyces, Penicillium and Scopulariopsis showed a marked capacity for OMW detoxification, depleting its antibacterial activity almost completely.  相似文献   

16.
北京夏植黄瓜内生真菌区系研究   总被引:1,自引:0,他引:1  
为了解黄瓜植株内生真菌的区系组成及其变化,从而为进一步研究黄瓜内生真菌的生态和功能奠定基础,对采自北京延庆的不同品种和不同生育期的40株黄瓜进行了内生真菌的分离培养。经形态学鉴定和18S rDNA序列分析,分离到的1,024株内生真菌属于18属,其中Exserohilum和Neocosmospora尚未见内生真菌的报道。Alternaria、Aspergillus、Chaetomium、Cladosporium和Fusarium在各生育期和各器官普遍存在。其中,Alternaria在叶中的定殖率达47.0%,远高于在其他器官中的定殖率;Fusarium在根中的定殖率达32.5%,远高于在其他器官中的定殖率。多数真菌类群表现出不同程度的器官偏好性,有些真菌类群则只出现在特定器官中。叶和根的内生真菌类群数量和总定殖率均高于茎和果实。随着黄瓜的生长,各器官内生真菌的类群数在增加,部分真菌的定殖率也呈上升趋势,但Neocosmospora和Chaetomium在各器官中的定殖率则随植株生长呈下降趋势。  相似文献   

17.
Seventy-eight species in addition to 1 variety of A. flavus belonging to 31 genera were collected from the rhizosphere (55 species + 1 variety and 24 genera) and phyllosphere (59 species and 22 genera) of Adiantum capillus-veneris, Ceterach officinarum, Asplenium filare and Cheilanthes catanensis.In the rhizosphere, the most common genera were Aspergillus, Penicillium, Fusarium, Mucor and yeasts. In the phyllosphere, the most prevalent fungi were Cladosporium herbarum, C. sphaerospermum, Alternaria alternata, Drechslera spicifera, Aspergillus spp., Penicillium spp., Cephalosporium roseo-griseum, Myrothecium verrucaria, Mucor racemosus and yeasts.  相似文献   

18.
We describe and interpret spatiotemporal micromycete community structure and adaptive complexes in contrasting xeric and mesic microclimates in the soils of 'Evolution Canyon' II, Lower Nahal Keziv, western Upper Galilee, Israel. A total of 192 species from 60 genera belonging to Zygomycota (nine species), Ascomycota (13 species), and mitosporic fungi (170 species) were isolated. The fungal communities on the south-facing, xeric, 'African' slope (AS) demonstrated significantly greater diversity than on the north-facing, mesic, 'European' slope (ES) and the valley bottom (VB). Seasonally, winter slope communities were less heterogeneous. Forest localities on the ES and the VB in all seasons and the shady localities on the AS in the winter were overwhelmingly dominated by mesophilic Penicillium species. The sunny locality on the AS was characterized by a dominance of melanin-containing micromycetes that was most pronounced in the summer and by high occurrence and abundance of thermotolerant and thermophilic Aspergillus and Fusarium species. Ascomycetes and zygomycetes were the minor components in all local mycobiota studied; sexual ascomycetes, being stress-selected fungi, were more than ten times more abundant in the soil of the AS than in that of the ES, with the peak of abundance in the sunny summer community. The results demonstrated a microscale adaptive spatiotemporal inter- and intraslope divergence in soil mycobiota structure. Microclimatic natural selection appears to be the major factor affecting soil fungus diversity patterns.  © 2003 The Linnean Society of London . Biological Journal of the Linnean Society , 2003, 78, 527–539.  相似文献   

19.
A study of the mycobiota in the digestive tract of 5 important species of triatomines, Triatoma brasiliensis, T. infestans, T. sordida, T. pseudomaculata and T. vitticeps, was made. The digestive tracts of 164 adults and 535 nymphs of those triatomines were studied and 393 fungal strains were isolated.The genera with the greatest number of species were Penicillium (19 species), Aspergillus (17 species) and Acremonium (5 species) and the most frequent species, in decreasing order, were Penicillium corylophilum, Aspergillus niger, Penicillium fellutanum, Cladosporium herbarum, Penicillium waksmanii, Aspergillus awamori and Paecilomyces variotii. Among the isolated fungi, we found species that are recognized as entomopathogenic and pathogenic for humans and animals.This revised version was published online in October 2005 with corrections to the Cover Date.  相似文献   

20.
Resistance of some common fungi to gamma irradiation   总被引:1,自引:0,他引:1  
Ten species of fungi representing the genera Alternaria, Aspergillus, Caldosporium, Curvularia, Fusarium, and Penicillium were examined for their relative resistance to gamma irradiation from a 137Cs source. Inactivation doses for dematiaceous fungi in agar medium ranged from 0.6 to greater than 1.7 megarads, whereas those for moniliaceous fungi were less than 0.3 megarad. D10 values (the dose required to reduce the inoculum by 1 log) for Curvularia geniculata (greater than 0.29 megarad) exceeded those for control spores of Bacillus pumilus (0.15 megarad).  相似文献   

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