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1.
Eleven new species of the genus Pseudocercospora were found on Byrsonima spp. from the Cerrado in Brazil: Pseudocercospora annellidica, P. byrsonimae-basilobae, P. byrsonimae-coccolobifoliae, P. byrsonimicola, P. byrsonimigena, P. campograndensis, P. grajauensis, P. mutabiliconidiophorum, P. pediformiconidiorum, P. planaltinensis, and P. subhyalina. The new species are described, illustrated and compared with hitherto described Pseudocercospora spp. on various hosts belonging to the Malpighiaceae, and all species concerned are keyed out.  相似文献   

2.
Four new Passalora species were found on leaves of Cerrado native plants of the genus Peixotoa (Malpighiaceae). Two of the new Passalora species (P. peixotae-reticulatae and P. cerradensis) belong in Section Mycovellosiella, while P. peixotoae-goianae and P.brasilianensis belong in Section Phaeoramularia.  相似文献   

3.
A new ascomycete genus placed in family Capnodiaceae found in the Brazilian Cerrado is described and designated Plurispermiopsis, type species P. cerradensis.  相似文献   

4.
Cercosporoid hyphomycetes on living leaves of plants were collected in Panama, identified, described, and illustrated. Newly described species are Passalora guraniae from Gurania sp. (Cucurbitaceae), Pseudocercospora arrabidaeae from Arrabidaea cf. candicans (Bignoniaceae), Pseudocercospora hymenaeae from Hymenaea courbaril (Caesalpinioideae/Fabaceae), Pseudocercospora solandrae from Solandra sp. (Solanaceae), and Verrucisporota struthanthicola from Struthanthus sp. (Loranthaceae). New reports for Panama are Cercospora glauciana from a new host plant genus (Rhynchospora, Cyperaceae), Pseudocercospora acalyphicola from a new host plant species (Acalypha macrostachya, Euphorbiaceae), Pseudocercospora cecropiae, Pseudocercospora cecropiicola, Pseudocercospora cecropiigena, Pseudocercospora mirandensis, and Ramularia rubella.  相似文献   

5.
Spatial autocorrelation is the lack of independence between pairs of observations at given distances within a geographical space, a phenomenon commonly found in ecological data. Taking into account spatial autocorrelation when evaluating problems in geographical ecology, including gradients in species richness, is important to describe both the spatial structure in data and to correct the bias in Type I errors of standard statistical analyses. However, to effectively solve these problems it is necessary to establish the best way to incorporate the spatial structure to be used in the models. In this paper, we applied autoregressive models based on different types of connections and distances between 181 cells covering the Cerrado region of Central Brazil to study the spatial variation in mammal and bird species richness across the biome. Spatial structure was stronger for birds than for mammals, with R(2) values ranging from 0.77 to 0.94 for mammals and from 0.77 to 0.97 for birds, for models based on different definitions of spatial structures. According to the Akaike Information Criterion (AIC), the best autoregressive model was obtained by using the rook connection. In general, these results furnish guidelines for future modelling of species richness patterns in relation to environmental predictors and other variables expressing human occupation in the biome.  相似文献   

6.
Annona crassiflora (Annonaceae) is a protogynous beetle-pollinated savannah tree species, widely distributed in the savannahs of the Cerrado biome. Studies on the mating system and pollen dispersal of protogynous species are very scarce. Here, we used six microsatellite loci to assess the mating system and pollen dispersal of A. crassiflora in a savannah remnant in Central Brazil. We mapped and sampled leaves of 112 adult trees and collected 74 fruits from 20 mother trees (1–4 fruits per plant) to obtain the seeds used (460) for mating system and parentage analyses. Annona crassiflora has predominantly allogamous mating systems, with a high multilocus outcrossing rate (tm?=?0.974, SE?=?0.011) that did not differ among mother trees (F?=?1.32, p?=?0.165). However, tmts was variable among seed trees, indicating that some seeds were produced by mating among relatives. Our results also showed multiple paternity within fruits. Multilocus correlation of outcrossed paternity was high (rp?=?0.302, SE?=?0.045), indicating that for each mother tree, the probability that the same pollen donor sired two random sibs was 30.2%, and the mean number of pollen donors per mother tree was high (6.3). We detected a maximum pollen dispersal distance of 360.7 m and an average of 124.3 m (SD?=?80 m), but most pollination events (73%) occurred at shorter distances (<?160 m), indicating short-distance pollen dispersal, most likely due to the pollinator behaviour.  相似文献   

7.
郭英兰 《菌物学报》2016,(5):545-548
报道2种中国假尾孢菌,其中有1个新种,即寄生在海南地黄连Munronia pinnata上的地黄连假尾孢Pseudocercospora munroniae;另1个是中国新记录种,即寄生在荜拔Piper longum上的胡椒生假尾孢Pseudocercospora piperigena。提供了各个种的形态描述、图及与近似种区别的讨论。研究的标本保存在中国科学院菌物标本馆(HMAS)。  相似文献   

8.
《Acta Oecologica》2006,29(1):9-15
Broad-scale correlations between species richness and human population suggest that processes driving species richness, mainly related to high ecological productivity, may also drive human populations. However, it is still under debate if this coincidence implies conflicts between biodiversity conservation and human development. In this paper, we analyzed the relationships among human population size, species richness and irreplaceability in Brazilian Cerrado. We analyzed a dataset with 131 species of anurans distributed in 181 cells with 1° of spatial resolution covering the biome. We found a positive correlation between human population size and anuran species richness (r = 0.46; P = 0.033 with 19.5 geographically effective degrees of freedom, v*), but the irreplaceability of each cell was poorly correlated with human population size (r = 0.075; P = 0.323; v* = 173.9). The 17 cells in the 97 optimal reserve networks contained a total human population ranging from 2942,195 to 4319,845 people, representing on average 11.8% of the human population in the entire Cerrado grid. The comparison of these observed values with 10,000 values from randomly generated networks suggests a relatively high flexibility in optimal complementarity sets for reserve selection. Our results indicated that correlation between richness and human population does not necessarily result in conflicts, given the opportunities for conciliating conservation and development. However, the analyses performed here are initial explorations within the framework of conservation biogeography, so more detailed studies are necessary to establish conservation planning at regional and local scales.  相似文献   

9.

Pollen grains have a relatively simple structure and microscopic size, with two or three cells surrounded by the protective sporoderm at maturity. The viability and efficiency of pollen transport from anther to stigma depends on pollen physiological properties, especially the relative water content of the vegetative cell. Pollen transport is a crucial fate for most angiosperms that depends on biotic pollinators and studies focusing on understanding the morpho-physiological properties of pollen grains are still scarce, especially to tropical open physiognomies as the Brazilian Cerrado. Therefore, we investigate some structural and physiological aspects of pollen grains from six native species naturally growing in one Cerrado area: Campomanesia pubescens (Myrtaceae), Caryocar brasiliense (Caryocaraceae), Erythroxylum campestre (Erythroxylaceae), Lippia lupulina (Verbenaceae), Pyrostegia venusta (Bignoniaceae), and Xylopia aromatica (Annonaceae). We selected dehiscent anthers and mature pollen grains to analyze (1) the anther wall and pollen microstructure, (2) the pollen water status at the time of anther dehiscence, and (3) the pollen chemical compounds. In all analyzed species, the anther and pollen developed in a successfully way, and except for Caryocar brasiliense, all species were able to emit pollen tubes in the germination tests. As expected for a dry and open environment, most species dispersed their pollen grains in a partially dehydrated form, as indicated by our harmomegathy experiment. As indicated by our study, the pollen ability in preventing dissection, maintaining its viability in a dry and hot environment during its transport from anther to stigma, may be related to the sporoderm apertures and to the reserve compounds, mainly carbohydrates in the form of hydrolysable starch grains.

  相似文献   

10.
Five new Stenella species were found on native cerrado plants. Stenella erythroxyli-campestris, S. erythroxyli-suberosi and S. erythroxylicola were associated with plant species belonging in the family Erythroxylaceae; S. cyrtopodii was found infecting the rare Cyrtopodium eugenii (Orchidaceae), and S. ocoteae occurred on Ocotea sp. (Lauraceae). Finally Parastenella callisthenis-fasciculatae was collected on a Vochysiaceae (viz. Callisthene fasciculate) endemic to the cerrado.  相似文献   

11.
As part of studies on cerrado fungi three new hyphomycetes are described in association with trichomes on leaves of native species of Qualea (Vochysiaceae). These are: Trichomatomyces gen. nov. (type species: T. byrsonimae comb. nov.), Trichosporodochium gen. nov. (type species: T. cerradensis sp. nov.), and Phaeoidiomyces gen. nov. (type species: P. qualeae).  相似文献   

12.
Among the ascomycete isolates from soil and armadillo dung collected in São Paulo State, Brazil, a new species ofEmericella, E. montenegroi and a new variety ofE. rugulosa, E. rugulosa var.Iazulina are described and illustrated.Emericella montenegroi differs from the other known species of the genus in having ascospores with an incompletely reticulate or ribbed ornamentation on the convex walls.Emericella rugulosa var.Iazulina differs from the type variety in having blue to violet color of ascospores. Isolations ofE. corrugata andE. foveolata are also reported as a South American record. A synoptic key to all accepted species of the genus is provided.  相似文献   

13.
Neosartorya udagawae, a new heterothallic species isolated from Brazilian soil, is described and illustrated. It is characterized by dull green colony on malt extract agar, light yellow large ascomata, broadly lenticular ascospores with two equatorial or several irregular crests and tuberculate convex surfaces, and with anAspergillus anamorph.Neosartorya aureola is also described as a new record from Brazilian soil.  相似文献   

14.
Coltricia globispora sp. nov. is described as new based on specimens collected in the Parque Natural Municipal de Porto Velho, in the state of Rondônia, Brazilian Amazonia. It is characterized by small pores (7–8 per mm), monomitic hyphal system, and globose, smooth and guttulate basidiospores (5.5–6.6 (?7) μm). Phellinus griseoporus has been found for the first time in Brazil, and Cyclomyces iodinus, P. merrillii, P. membranaceus and P. umbrinellus in the Brazilian Amazonia. Coltricia cinnamomea, P. calcitratus and Phylloporia chrysites are new occurrences to the state Rondônia, while C. hamata and Phylloporia spathulata to the state of Pará. The knowledge about Hymenochaetaceae in the Brazilian Amazonia is briefly discussed, and a key to the neotropical species of Coltricia is provided.  相似文献   

15.
In this study, we aimed to assess whether free-ranging wild canids are exposed to heavy metals in one of the most developed and populated regions of Brazil. Hair of 26 wild canids (maned wolves Chrysocyon brachyurus, crab-eating foxes Cerdocyon thous, and hoary foxes Lycalopex vetulus) from the Cerrado biome in Southeast Brazil were analyzed by spectrophotometry to detect cadmium, chromium, and lead, and also the essential copper, iron, manganese, and zinc traces. All samples showed traces of copper, iron, manganese, and zinc. Non-essential lead was detected in 57% (2.35 ± 0.99 mg/kg), and chromium in 88% (2.98 ± 1.56 mg/kg) of samples. Cadmium traces (detection limit 0.8 mg/kg) were not found. Crab-eating foxes had more copper, iron, and manganese in hair than maned wolves. Correlations among element levels differed between maned wolves and crab-eating foxes. Concentrations of chromium and lead were outstandingly higher than in wild canids from other areas. Addressing the causes of such levels and the impacts of the heavy metal pollution in Neotropical ecosystems is urgent for animal health and conservation purposes. We argue that heavy metal pollution should be considered as dangerous threats to wildlife health in Brazil and recommend hair sampling as a biomonitoring tool for heavy metals in Neotropical terrestrial mammals.  相似文献   

16.
Anuracanthorhynchus tritaxisentis n. gen., n. sp. from the intestines of the Brazilian frog Hylodes phyllodes (Leptodactylidae) is described and illustrated. Anuracanthorhynchus tritaxisentis n. gen., n. sp., is unique among the echinorhynchid Acanthocephala by possessing a spherical proboscis supporting a small number of hooks of equal size. It is the sixth acanthocephalan species reported from South American anurans.  相似文献   

17.
Helicoma chiayiense sp. nov. and Helicosporium taiwanense sp. nov. on decaying wood submerged in a freshwater stream of Alishan area, Chiayi County, Taiwan, are described and illustrated with light and scanning electron micrographs. Helicoma chiayiense is distinct in having hyaline conidiophores arising from repent mycelium, producing broad conidia that bear secondary conidia. Helicosporium taiwanense is distinct in having robust poly-denticulate conidiophores producing conidia with a wide conidial filament. The phylogenetic relationship of these species was sought among representative taxa of the helicosporous hyphomycetes by comparing their ITS of the ribosomal DNA (rDNA).  相似文献   

18.
Pseudobombax tomentosum and P. longiflorum are common trees in the Cerrado region, but the former species is more common in forest edges while the later is present in open cerrado areas. This work aimed to investigate differences in seed germination and seedling growth in these species, from seed collected from Cerrado areas in Central Brazil. For this, a seed germination experiment was designed and included four replicates with 25 seeds per species; seeds were randomly distributed in the germination chamber. To evaluate initial seedling growth, seedlings height was measured up to 67 days after seedling emergence; besides, some of these seedlings were grown for biomass evaluation during nine months. Results showed that seeds of the two species had the same germinability (near 100%) and mean germination time (ca. 12 days). However, P. longiflorum showed a more spread seed germination through time, with higher values of coefficient of variation in germination time and uncertainty index; and lower values of synchronization than P. tomentosum. The two species showed basically the same growth pattern, but lower values for height of apical meristem, diameter of underground structures (mostly roots), dry mass of shoots, underground structure and total mass of seedlings in P. tomentosum were obtained, compared to P. longiflorum. Both species allocated more dry mass to underground structures in detriment of shoot. This probably allows resprouting behavior which prevents hydric stress and detrimental fire action typical of the open Cerrado areas.  相似文献   

19.
In the course of studies about conidial fungi that grow on plant debris in the semi-arid region of Brazil, four species of Paliphora were found on unidentified dicotyledonous plants. Paliphora intermedia and P. porosa are recorded for the first time for South America and the neotropics respectively. Paliphora inflata and P. multiseptata are proposed as new species. A key and synoptic table of characters of the five known species of Paliphora are provided.  相似文献   

20.
The antimicrobial activity of copaiba oils was tested against Gram-positive and Gram-negative bacteria, yeast, and dermatophytes. Oils obtained from Copaifera martii, Copaifera officinalis, and Copaifera reticulata (collected in the state of Acre) were active against Gram-positive species (Staphylococcus aureus, methicillin-resistant S. aureus, Staphylococcus epidermidis, Bacillus subtilis, and Enterococcus faecalis) with minimum inhibitory concentrations ranging from 31.3-62.5 microg/ml. The oils showed bactericidal activity, decreasing the viability of these Gram-positive bacteria within 3 h. Moderate activity was observed against dermatophyte fungi (Trichophyton rubrum and Microsporum canis). The oils showed no activity against Gram-negative bacteria and yeast. Scannning electron microscopy of S. aureus treated with resin oil from C. martii revealed lysis of the bacteria, causing cellular agglomerates. Transmission electron microscopy revealed disruption and damage to the cell wall, resulting in the release of cytoplasmic compounds, alterations in morphology, and a decrease in cell volume, indicating that copaiba oil may affect the cell wall.  相似文献   

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