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1.
Seventy-five species in addition to 5 varieties of cellulose-decomposing which belong to 27 genera were collected during this investigation. Aspergillus (12 species + 4 varieties), Alternaria (4 species), Stachybotrys (3 species + 1 variety), and Penicillium (12 species) were of high frequency of occurrence, of which A. fumigatus, A. niger, A. terreus, A. alternata, A. tenuissima, S. atra, P. citrinum and P. corylophilum were the most common. Six genera were of moderate frequency and these were Botryotrichum (2 species), Macrophomina (1 species), Drechslera (5 species), Ulocladium (4 species), Chaetomium (7 species) and Curvularia (4 species) of which B. atrogriseum, D. spicifera, D. sativus, Ubotrytis, C. spirale and C. lunata were the most prevalent. Five and twelve genera were recovered on cellulose-Czapek's agar plates in low and rare frequency of occurrence, respectively.  相似文献   

2.
《Journal of bryology》2013,35(2):137-146
Abstract

Epiphytic bryophytes were studied on two tree species with different bark characteristics (Alnus glutinosa and Carpinus betulus) in two vertical ranges (0–60 and 60–200 cm height above ground on the trunk) in a stream valley in the Carpathian Basin (N.W. Hungary). There is a significant difference in the species composition of the trees. Dicranum montanum and Platygyrium repens occurred significantly more often on Alnus glutinosa, whereas Frullania dilatata and Radula complanata were more often on Carpinus betulus in both vertical ranges. Orthotrichum species were typical only in the vertical range 60–200 cm on Carpinus betulus, whereas Plagiothecium nemorale and Metzgeria furcata were typical of Alnus glutinosa and Carpinus betulus, respectively, in the vertical range 0–60 cm. Although most of the bryophyte species have significant phorophyte preferences, Hypnum cupressiforme (in both vertical ranges) and Isothecium alopecuroides (in vertical range 0–60 cm) are indifferent in this respect. Our findings showed clearly that phorophyte preference and vertical position on the trunk are not independent variables. We investigated the independence of the frequencies and abundances of bryophyte species in the two vertical ranges separately on the two tree species. The species form four different groups: (1) species with greater abundance in the higher vertical range; (2) species with smaller abundance in the higher vertical range; (3) indifferent species with nearly uniform abundances in both vertical ranges; (4) species present only in one vertical range. It was found that even a single bryophyte species can show different vertical preferences depending on tree species. No significant relationships were found between the abundances of bryophytes and distance from the stream, slope of the bark surface and trunk circumference. Species-specific traits appear to explain individual phorophyte preferences; however, in several cases chemically mediated effects of the bark appeared to be important.  相似文献   

3.
Food plant preferences of some Lepidoptera species associated with particular colour of the flowers were investigated. Based on 1,329 field observations of 43 Lepidoptera and 66 plant species, Lepidoptera showed a high tendency (G-test, G adj = 698.6, df = 6, P < 0.001) to use the yellow (29%) and pink (28%) coloured flowers for foraging. Compared to the other colours it was evident that plants with red flowers (2%) were not preferred. Moreover, the plants with red (H = 0.435) and yellow-white (H = 0.543) flowers were not visited by diverse Lepidoptera species. Although yellow and pink flowers were most frequently visited, the highest degrees of the Lepidoptera diversity values were associated with the plants having blue (H = 0.647) and purple (H = 0.634) flowers. Species of Nymphalidae were most numerous (14 spp.) in the study area and the members of this family were observed 430 times on 39 different plant species, but never on plants with red flowers. Pieris rapae was the most abundant species that occurred 136 times on a total of 21 different plant species of which eight had yellow flowers. But, this species has never been seen while feeding on red flowers.  相似文献   

4.
DNA barcodes were studied for 1,353 specimens representing 272 morphological species belonging to 149 genera and 55 families of Perciformes from the South China Sea (SCS). The average Kimura 2‐parameter (K2P) distances within species, genera and families were 0.31%, 8.71% and 14.52%, respectively. A neighbour‐joining (NJ) tree, Bayesian inference (BI) and maximum‐likelihood (ML) trees and Automatic Barcode Gap Discovery (ABGD) revealed 260, 253 and 259 single‐species‐representing clusters, respectively. Barcoding gap analysis (BGA) demonstrated that barcode gaps were present for 178 of 187 species analysed with multiple specimens (95.2%), with the minimum interspecific distance to the nearest neighbour larger than the maximum intraspecific distance. A group of three Thunnus species (T. albacares, T. obesus and T. tonggol), a pair of Gerres species (G. oyena and G. japonicus), a pair of Istiblennius species (I. edentulous and I. lineatus) and a pair of Uranoscopus species (U. oligolepis and U. kaianus) were observed with low interspecific distances and overlaps between intra‐ and interspecific genetic distances. Three species (Apogon ellioti, Naucrates ductor and Psenopsis anomala) showed deep intraspecific divergences and generated two lineages each, suggesting the possibility of cryptic species. Our results demonstrated that DNA barcodes are highly reliable for delineating species of Perciformes in the SCS. The DNA barcode library established in this study will shed light on further research on the diversity of Perciformes in the SCS.  相似文献   

5.
Three species of the genus Cacopsylla were collected from Sorbus japonica in Japan. Two of them, Cacopsylla elegans and Cacopsylla sorbicoccinea, are described as new species based on adults and fifth (final) nymphal instars. The third species, Cacopsylla midoriae, is newly transferred from the genus Psylla. The adult of C. midoriae is redescribed and the nymph is described for the first time. A key to the species feeding on S. japonica (adults and nymphs) is provided. The three species were observed to coexist on the same tree of S. japonica in northern Kyushu. Such coexistence of psylloid congeners is uncommon in Japan.  相似文献   

6.
Maghazy SM 《Mycopathologia》2002,154(4):171-175
In order to estimate the prevalence of dermatophytes and other fungi on healthy children hairs and nails, 92 hair samples and 85 nail samples (groups of 10 finger nails from each child) were collected from 5 nurseries (children aged 9 months up to 4 years) in Assiut city. From hair samples 22 species were collected, Trichophyton (2 species) and Microsporum (2 species) were the only recovered dermatophytes in addition to well known keratinophilic genus Chrysosporium (4 species). From nail samples, 18 species were identified, Trichophyton was represented by 4 species, Microsporum, 2 species and Chrysosporium, 4 species. Also, several other saprophytes and cycloheximide resistant fungi were isolated. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

7.
Abstract

A survey of planktonic dinoflagellates and related cysts was carried out in the Gulf of Trieste throughout one year from April 1992 to March 1993. 113 taxa were recovered by the analysis of phytoplankton net samples. The most represented genera were Protoperidinium (34 species), Ceratium (24 species), Dinophysis (15 species), Gonyaulax (11 species) and Prorocentrum (8 species). A particular attention was given to potentially toxic species belonging to the genera Dinophysis, Alexandrium and Prorocentrum. The highest number of species (67 species) was recorded in July, and the lowest one (18 species) in February.

33 cyst morphotypes were recorded by the analysis of sediment samples. The most represented genera were Protoperidinium (8 morphotypes), Scrippsiella (3 morphotypes), Gonyaulax (3 morphotypes) and Alexandrium (2 morphotypes); the cysts most frequently found were those of Conyaulax polyedra and Alexandrium pseudogonyaulax.  相似文献   

8.
The distribution, species composition and abundance of carabid beetles in monospecific plantations of three different coniferous tree species (Japanese spruce, Sakhalin fir and larch) were investigated by baited pitfall traps in Hokkaido, Japan. In total, 16 150 carabid beetles consisting of 31 species in 13 genera were collected in 2011 and 2012. The most predominant species was Pterostichus thunbergii Morawitz, followed by Synuchus melantho (Bates) and Carabus opaculus (Putzeys). Average numbers of beetles per trap were significantly reduced in larch. Large‐sized Carabus species (C. arboreus arboreus Lewis and C. opaculus) were collected in large numbers in Japanese spruce. There was no significant difference in diversity and equitability among the three kinds of plantation. The ordination of redundancy analysis showed that medium‐sized forest generalists, Pterosticus subovatus (Motschulsky) and P. thunbergii, were highly associated with Japanese spruce and Sakhalin fir, and the forest specialist Synuchus nitidus (Motschulsky) was with Sakhalin fir. In contrast, in larch there was no such associated forest species, and some species of Carabus, Pterostichus and Synuchus were considerably reduced in number, suggesting that larch has unfavorable effects on some forest species. The most important environmental variables influencing carabid assemblages were soil moisture and foliage layer cover. Practices in forest management to minimize the effects of plantations on carabid assemblages are discussed.  相似文献   

9.
In a survey on heterostigmatic mites (Acari: Prostigmata: Heterostigmata) associated with insects including ants in northwestern Iran, two new species of myrmecophilous mites of the genus Scutacarus (Acari: Scutacaridae) were found. They are S. shajariani sp. nov. phoretic on Tetramorium sp. (Hymenoptera: Formicidae) and S. ebermanni sp. nov. phoretic on Messor sp. The mentioned new species belong to groups of species with reduced setae e and h2, and no setae 4b, respectively. These two new species are described and illustrated, and world keys are provided for respective species groups.  相似文献   

10.
The effects of salinity on the reproduction of coastal submerged macrophyte species were studied on samples of communities from six seasonal marshes in two outdoor experiments performed in autumn and in spring. The submerged macrophyte communities were submitted to five different salinity levels (0, 1, 2, 4 and 6 g/1 Cl?1). In a companion paper (Grillas, van Wijck & Bonis 1993) three groups of species were distinguished on the basis of their biomass production over the salinity range 0 to 6 g/1 Cl?1: (1) glycophytes (non-salt-tolerant species), (2) salt-tolerant species and (3) halo-phytes. This part of the study describes the impact of salinity on the reproduction of the individual species during the two experiments. The species differ in their capacity to reproduce in the autumn; only Zannichelliapedunculata and Tolypella hispánica were able to produce fruits in that season. For all species reproduction was greater in spring and strongly correlated with biomass, except for Chara canescens. Differences in reproductive effort over the salinity range amplified the halophytic nature of Ruppia marítima and Chara canescens and the intolerance of Callitriche truncata and Chara contraria. For the other species, reproductive effort did not differ significantly over the salinity range. Regarding the effect of salinity on biomass and reproductive effort of individual species, there were large differences in the total weight of propagules produced at the community level and in the relative contribution of individual species. The resulting quantitative changes in the species composition of the seed bank could affect the structure of the communities by their effects on the establishment and survival of species populations.  相似文献   

11.
Sixty-nine species and four varieties that belong to 28 genera of terrestial fungi were recovered from polluted and non-polluted water and mud samples on glucose and cellulose-Czapek's agar at 28°C. The most common species from the two substrates on the two types of media were Aspergillus flavus, A. fumigatus, A.niger, Cladosporium cladosporioides, Fusarium oxysporum, Mycosphaerella tassiana and Penicillium chrysogenum. Twenty-six species belonging to 14 genera were isolated from polluted (26 species and 14 genera) and non-polluted (17species and 10 genera) mud samples on Sabouraud's dextrose agar at 28°C. The most prevalent species were Acremonium retiulum, Alternaria alternata, Aspergillus flavus, Aphanoascus fulvescens, A. terreus, Aphanoascus sp., Penicillium funiculosum and Stachybotrys chartarum.  相似文献   

12.
We tested whether differences in the herbivory tolerance of plant species is related to their abundance in grassland communities and how herbivory and nutrient availability affect competitive balances among plant species through changes in their tolerance. The experimental approach involved a simulated grazing treatment (clipping) of two competitive grass species (Arrhenatherum elatius and Holcus lanatus) and two subordinate forb species (Prunella vulgaris and Lotus corniculatus) along a gradient of nutrient availability and under conditions of competition. Total standing, aboveground, root, and regrowth biomass were evaluated at the end of the experiment as an estimate of the capacity to compensate for twice removing aboveground biomass at different nutrient levels (NPK). Although clipping had a more pronounced negative effect on dominant plant species (Arrhenatherum and Holcus) than on subordinate species, the negative effects on dominant species were offset by the application of fertilizer. The combined effect of fertilizer and competition had more negative effects on the performance of Lotus and Prunella than on the dominant species. In terms of competition, the regrowth ability of Arrhenatherum and Holcus increased with the application of fertilizer, while the opposite pattern was observed for Lotus and Prunella. The addition of fertilizer has a positive effect on both grass species in terms of growth in clipped pots and competition, while subordinate species did not respond to the addition of fertilizer to the clipped pots and were negatively affected by competition with both grass species. The results suggest (1) that species replacement towards subordinate species as a function of herbivory is partially dependent on the herbivory tolerance of that species, (2) competitive relations between competitive grass species and subordinate forb species change under different environmental conditions, and (3) although grazing disturbance significantly influences competitive relations in favor of less competitive species, increasing nutrient levels counteract the negative effect of grazing on dominant competitive plant species.  相似文献   

13.
唐梦  陈静  杨灵懿  贾翔  刘济铭  段劼 《生态学报》2023,43(24):10156-10170
生物燃油树种是发展生物质能源,实现化石能源替代战略的重要物质基础,明确当前和未来气候变化下我国生物燃油树种适生区分布,对保护和利用生物燃油树种,促进林业生物能源产业发展,保障能源安全和实现“双碳”目标具有重要意义。基于我国10个主要生物燃油树种的1037条树种分布数据和20个环境变量,利用最大熵模型(MaxEnt)预测了各树种当前和未来气候情景下(2050年和2070年的RCP4.5情景)的潜在适生区,得到了影响各树种分布贡献率最大的环境因子,并对我国各区域主要种植树种进行了区划。结果表明:(1)MaxEent模型预测效果较好,各树种模拟结果AUC值均在0.9以上。(2)影响各种分布的贡献率较高的环境因子因树种而异,最暖季度降水量和温度季节性变化标准差的相对贡献率较高。(3)10个生物燃油树种极高适生区面积范围在43.38万km2—117.74万km2之间,可根据模拟结果将树种分布划分为北部、中东部、东南部和西南部4个亚区,北部亚区主要树种为文冠果(Xanthoceras sorbifolium)和欧李(Cerasus humilis),中东...  相似文献   

14.
Generalist predators and the prey species Frankliniella occidentalis (Pergande) were periodically sampled from 64 weed species to determine their numerical interrelationships in three ecologically different locations in the eastern Mediterranean region of Turkey in 2002–2003. Adult and nymph stages of seven hemipteran predator species were recorded: Deraeocoris pallens Reuter, Geocoris arenarius (Jakovkev), Nabis punctatus Costa, Orius laevigatus Fieber, Orius majusculus (Reuter), Orius niger (Wolff) and Piocoris erythrocephalus (Peletie and Serville). The most common and abundant predator species was O. niger, which was found on 53 weed species in the winter–spring and summer–fall periods; the highest total numbers of O. niger adults per weed species were 139, 275, 266 and 325 on Urtica urens, Sinapis arvensis, Lamium amplexicaule and Mentha aquatica, respectively. Relatively higher numbers of Orius spp. nymphs were detected on the weed species Echium plantagineum, Cichorium intybus, Heliotropium europeum, Mentha aquatica and Polygonum aviculare. Orius spp. were attracted to flowers in significantly higher numbers than to leaves of the investigated weeds. No significant correlation was found between the numbers of Orius spp. and F. occidentalis on the major weed species, except E. plantagineum. These findings suggest that weeds may provide Orius spp. with resources other than prey, such as nectar and pollen, shelter, and breeding sites. The weed species on which relatively higher numbers of Orius adults and nymphs were found may be considered as candidates for studies aiming to include weeds to enhance integrated pest management of F. occidentalis on crops.  相似文献   

15.
Abstract. Seed mortality (caused by predators and pathogens) and germination were compared between Puerto Rico and Costa Rica on landslides in lower montane wet forest. Seeds of six common species on five Puerto Rican landslides and four common species on two Costa Rican landslides were used with a Cecropia species and a Gonzalagunia species included at both sites. In the Puerto Rican experiments Cecropia schreberiana was the only species to show significant seed predation (which was due to insects), pathogens grew from all species and fewer seeds were lost to predators than pathogens. Also in Puerto Rico mean germination across all species was 57 % before dispersal (filled seeds collected while still on the tree) and 71 % after, with Phytolacca rivinoides seeds germinating most abundantly, followed in descending order by Ocotea leucoxylon, Cecropia spec, Miconia racemosa, Palicourea riparia and Gonzalagunia spicata. In the Costa Rican experiments three species had significant predation: Cecropia polyphlebia and Urera caracasana (both due to insects) and Witheringia coccoloboides (due to mammals); pathogenic disease caused more seed loss than predation, and germination was high (61 % pre-dispersal, 69 % post-dispersal). Similarities between these island and mainland sites included (1) percentage of seeds lost to predation and percentage lost to pathogens (all in the 5–15 % range), (2) generalist pathogens which claimed more seeds than predators and (3) majority germination with a general increase after dispersal. Finally sites were dissimilar only in the number of species with significant predation loss and whether it was by insects or mammals, casting doubt on the traditional island/mainland dichotomy.  相似文献   

16.
According to the data obtained, the Mordovian fauna of diurnal lepidopterans comprises 75 species, including Hesperiidae (7 species), Papilionidae (5), Pieridae (10), Satyridae (10), Nymphalidae (27), and Lycaenidae (16). Based on the quantitative assessments, the species were characterized as rare (1–5 ind. in the collection), scarce (6–30), common (31–170), and abundant (171–940). Species with temperate (52 species or 69.3%) and subboreal (12 species or 16.0%) ranges predominated in the latitudinal distribution pattern. The total and background species diversity of the Diurna was the highest in the forests (63 species) and meadows (52), and the lowest on the steppe slopes (6). Among the species revealed, 14 were rare: Iphiclides podalirius, Zerynthia polyxena, Parnassius apollo, Driopa mnemosyne, Colias erate, Coenonympha hero, Neptis sappho, Apatura iris, Limenitis populi, Nymphalis antiopa, Fixsenia pruni, Lycaena helle, Cupido minimus, and Maculinea arion.  相似文献   

17.
A morphometric approach proved useful for characterizing pollen from the Ambrosia species that are responsible for most ragweed hayfever and for correctly identifying individual pollen grains. Pollen was harvested from 4 species (A. trifida, A. artemisiifolia, A. bidentata, A. psilostachya) grown in Champaign County, Illinois, and observed with a scanning electron microscope. Quantitative measurements of 6 different exine characters were made on micrographs of 96 pollen grains from each species. Discriminant analysis based on these characters was used to obtain a population centroid for each species and indicated that these centroids were distinctly different. This analysis also included a species classification for individual pollen grains and indicated probability of species membership. About 86% of all individuals were correctly classified when the 4 species were included, with a range from 80% (A. artemisiifolia) to 95% (A. psilostachya). When three species (A. trifida, A. artemisiifolia, A. bidentata) were analyzed, about 87% of the individuals were correctly classified, and almost all individuals (97%) were classified correctly when only A. trifida and A. artemisiifolia were included. The validity of the derived discriminant functions was also tested by treating herbarium specimens as unknowns. The species and percentages of these individuals correctly classified were A. trifida (100%), A. artemisiifolia (58%), A. bidentata (100%), and A. psilostachya (31%). The classification results using three species were A. trifida (100%), A. artemisiifolia (75%), and A. bidentata (100%); and using two species were A. trifida (100%) and A. artemisiifolia (92%). Hence, the disciminant functions do seem valid for 3 species, but further investigation of A. psilostachya is needed. This type of approach may be useful in pollen analysis, especially where these species significantly contributed to aeroallergens.  相似文献   

18.
Using the seed-plate method on glucose-Czapek's agar at 28 °C (±2 °C), 24 genera and 60 species in addition to two varieties were collected from bean, broad bean, lentil, lupine and pea seeds. The most frequent genera were Aspergillus (16 species + two varieties), Penicillium (14 species), Rhizopus (1 species) and Yeasts, followed by Fusarium (3 species), Mucor (4 species) and Drechslera (3 species). From the preceding genera, Aspergillus niger, A.flavus, Penicillium citrinum, Rhizopus stolonifer, Fusarium moniliforme or F. oxysporum, Mucor hiemalis or M. racemosus and Drechslera spicifera were the most prevalent species.  相似文献   

19.
Spiders were collected by sifting leaf litter of three common tree species, Cussonia paniculata sinuata, Olea europaea africana and Searsia lancea, in an undisturbed grassland habitat in central South Africa. The study aimed to collect baseline data on spider assemblage structure, seasonality and the effects of litter structure on spider assemblages. In total, 1385 spiders were collected, representing 26 families and 56 species. Four species, Obatala sp. (Amaurobiidae, 22.7%), Camillina maun Platnick & Murphy (Gnaphosidae, 17.0%), Proevippa sp. (Lycosidae, 11.4%) and Zelotes frenchi Tucker (Gnaphosidae, 9.2%) dominated the fauna. Spider abundance was the highest in Olea litter (n = 607), followed by Searsia (n = 453) and Cussonia (n = 325). Searsia had the greatest number of species (41 spp.), followed by Olea (35 spp.) and Cussonia (30 spp.). Both spider abundance and species richness per sample varied significantly between the tree species. Of the ten most abundant species, all but two showed a significant preference for particular litter types. Mean spider abundance and species richness per sample were the lowest in Cussonia litter, which was the deepest litter type, but with the most interstitial space, whereas mean abundance and species richness per sample were the highest in Olea litter, which was the shallowest and moderately compact in structure.  相似文献   

20.
Abstract

To investigate the phylogenetic relationships between Leymus and related diploid species of the Triticeae tribe, the esterase isozyme (EST), superoxide dismutase (SOD) isozymes, and genome-specific random amplified polymorphic DNA (RAPD) markers were used to analyze for 14 Leymus species, together with two Psathyrostachys species (Ns), three Pseudoroegneria species (St), two Hordeum species (H), Lophopyrum elongatum (Ee), Australopyrum retrofractum (W), and Agropyron cristatum (P). The data were used to construct dendrograms by means of UPGMA in the NTSYS-pc computer program. The results suggested that (1) isozyme analysis can be used in the systematic studies of these perennial Triticeae; (2) there is a close relationship between Leymus, Psathyrostachys juncea, three Pseudoroegneria species, and Lophopyrum elongatum; (3) the Ns genome-specific RAPD marker was present in all 14 polyploid species of Leymus, while the Ee and P genome-specific RAPD markers were absent in 14 polyploid species of Leymus; the St, W and H genome-specific RAPD markers were present in some species of Leymus; (4) Leymus species have multiple origins, and different Leymus species derived their genomes from different donors.  相似文献   

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