Fruiting ofLyophyllum tylicolor in plate culture on Soytoneglucose agar and urea-treated soil extract agar

Lyophyllum tylicolor, which forms mycelial basidia (and basidiospores), produced fruit-bodies when cultivated at 20°C under continuous illumination of 400–700 lux on agar plates containing Bacto-Soytone and glucose or an extract from urea-treated soil. Under these conditions, mycelial basidia were also observed on the Soytone-glucose agar, but not on the soil extract agar. In darkness, fruit-bodies and mycelial basidia were not observed on either medium. In culture on the soil extract agar, fruit-body primordia were produced at the position of the margin of the colony when it was transferred from darkness to continuous light; stipes did not elongate under illumination of ca. 2000 lux; and mycelial basidia and basidiospores, but not fruit-bodies, developed when glucose concentration in the medium was as high as 1% (w/v).     

Taxonomy ofPenicillium nalgiovense isolates from mould-fermented sausages

A large number ofPenicillium nalgiovense isolates from mould fermented sausages and the ex type culture were examined for characters of morphology, physiology and production of secondary metabolites. To separate biotypes within theP. nalgiovense species, the data obtained were evaluated using multivariate statistical methods. The macromorphological characters of the ex type culture and isolates from meat products appeared to be distinctive. The ex type culture is characterized by a brown reverse on both Czapek yeast extract and malt extract agar while the isolates from meat products have a yellow to orange reverse. Proteolytic and/or lipolytic activity was demonstrated by 75% of the examined cultures and all of them demonstrated ability to utilize lactate as sole carbon source. Growth on creatine sucrose agar was very inhibited and acid production was absent or very weak. TLC analysis showed production of three unknown secondary metabolites that constituted the characteristic profile. HPLC analysis showed production of only three known secondary metabolites; chrysogine (96%), nalgiolaxin and nalgiovensin (9%). The ex type culture produced nalgiolaxin and nalgiovensin but not chrysogine. The chemometric evaluation showed thatP. nalgiovense isolates from meat products from a homogenous species, which can not be divided into biotypes. The only indication of grouping, beside a separation of the ex type culture, was related to the conidium colour (white, turquoise or grey green). The examinedP. nalgiovense isolates showed some resemblance (morphologically and chemically) toP. chrysogenum.     

不同植被类型植物物种多样性

为了评价大面积人工种植杜仲对当地植物多样性的影响,以河南省汝阳县不同植被类型为研究对象,通过群落学调查,运用重要值、Shannon-Wiener物种多样性指数(H)、Simpson物种多样性指数(D)和均匀度指数(JH')等指标,统计分析杜仲人工林、温带落叶阔叶林(以下简称次生林)和撂荒地3种不同植被类型的植物物种多样性,探讨杜仲种植对植物多样性的影响。调查发现,杜仲林样地中出现植物82种,隶属39科63属,草本层为最发达的一层;次生林样地中出现植物70种,隶属32科62属,乔木层为最发达层;撂荒地样地中出现植物84种,隶属35科69属,无乔木层。杜仲林物种丰富度和多度均不亚于次生林和撂荒地,且杜仲林草本层物种丰富度和植株总数均高于次生林。统计分析显示,杜仲林乔木层、灌木层和草本层多样性指数H和D值、均匀度指数JH'值与其它两种植被类型相比无显著性差异(P0.05)。因此,种植杜仲过程中采用合理密度,适当管理,不仅能提供叶、花、果等资源,而且能够丰富草本植物的种类和数量,增加植物物种多样性。     

Efficacy of seed-based media for the mould-yeast conversion of Blastomyces dermatitidis

The efficacy of 20 seed-based media is reported for the in vitro mould-yeast conversion of Blastomyces dermatitidis, employing pharmamedia agar, peptone glucose agar, glucose agar and water agar as controls. The mould-yeast conversion varied significantly according to the culture medium, fungal strains and incubation period (p<0.01). Garden-pea, chick-pea, cow-pea, soyabean, peanut, green gram, French bean, lentil, okra and cottonseed converted all of the 7 B. dermatitidis test strains after 5 days of incubation at 37 ° C. Although the efficacy of many of these seed media was found to be at par with pharmamedia agar — a commercial cottonseed embryo-derived protein, garden-pea seed agar is adopted because of the wider availability and low fat content of this seed. The recommended composition of the medium comprises 2% aqueous seed extract, 2% glucose and pH 6–7. Only nigerseed and sunflower seeds failed to support the conversion of B. dermatitidis. Of the control media, peptone glucose agar, glucose agar and water agar did not support the conversion of 2 of the B. dermatitidis test strains. The mechanism underlying variable mould-yeast conversion of B. dermatitidis on seed-based media is not clearly understood. However, most of the seeds supporting excellent mould-yeast conversion are known for their high protein content. The conversion was apparently not affected by the fat content of the seeds or by incorporation of glucose in the medium.     

Canthaxanthin pigment does not maintain color in carmine bee-eaters

Carmine bee-eaters (Merops nubicus) in captivity lost feather color when fed diets supplemented with canthaxanthin (23 mg/kg dry matter), a pigment and concentration known to maintain adequate color in numerous other bird species. Supplementation of whole insects with natural mixed carotenoids including α- and β-carotene, zeaxanthin, cryptoxanthin, and lutein resulted in a quantifiable change in feather color in this species. Positive identification of feather pigments and elucidation of metabolic pathways of color production in bee-eaters remain to be completed; initial data suggest α-carotene or derivatives as primary pigments or precursors in this species. © 1996 Wiley-Liss, Inc.     

Carotenoids of the lily beetle (Lilioceris lilii) and of its food plant (Lilium hansonii)

Six carotenoids were identified in the leaves of Lilium hansonii, and of these, only two, namely β-carotene and 5,6-monoepoxy-β-carotene were found in the lily beetle. Further, 4-OH, 4,4¹-di-OH, and keto-carotenoids were found either in the larvae or in the adults of the beetle. As these were not found in its food plant, the insect must have been able to convert ingested carotenoids into these compounds. The presence of isozeaxanthin and absence of cantaxanthin in the larvae while both compounds were found in the adults suggest a precursor-product relationship. This is in agreement with possible pathways leading to the formation of keto-carotenoids.     

Survey on the mycoflora of Egyptian wheat grains and their lemmae and paleae

The plating technique has been used to study the fungus floras of covered and uncovered wheat grains and their lemmae and paleae on glucose-cellulose and 40% sucrose-Czapek's agar at 28° C. Seventy-two species and 28 genera were collected from the three microhabitats on the three types of media. On glucose-Czapek's agar the most frequent species were Aspergillus niger, A. flavus, A. terreus, A. nidulans, Alternaria alternata, Cladosporium herbarum and Fusarium Oxysporum. On cellulose and 40% sucrose-Czapek's agar, the composition of fungal floras of the three substrates and the frequency of prevalence of the individual fungi were basically similar to those obtained on glucose agar, but the frequency of some species was promoted or decreased.     

Functional aspects of secondary carotenoids in Haematococcus lacustris (Girod) Rostafinski (Volvocales). V. Influences on photomovement

Secondary carotenoids are suspected to modulate photomovement in Haematococcus lacustris [Girod] Rostafinski (Volvocales). To investigate the influence of these extrachloroplastic ketocarotenoids on phototactic and photophobic responses in the flagellate stage of the green alga, flagellate suspensions differing in the content of secondary carotenoids were grown from green and red aplanospores. Photo-orientation of these flagellates induced by unilateral irradiation was investigated using a computer-aided system for microscopic image analysis. Results were hypothetically summarized as follows: (1) Diminution of precision of the positive phototaxis was found in red flagellates. This might be due to cellular shading of the blue-light-sensitive photoreceptor by secondary carotenoids. (2) Red flagellates exhibited an increase in the photophobic response. This finding is discussed in relation to an adaptive increase of the photoreceptor sensitivity, thought to be a result of the higher optical density of the corresponding cell suspension in the blue wavelength region.     

Physiological characteristics of cyanobacteria in pulp and paper waste-treatment systems

An investigation was made into the physiological characteristics of the extensive cyanobacterial communities in pulp and paper secondary waste-treatment systems, including the capacity of isolates to biodegrade organic contaminants in these systems. Although pulp and paper waste-treatment systems were found to be severely light-limited, photosynthesis-irradiance curves indicated that shade-adapted cyanobacterial communities could fix conspicuous amounts of inorganic carbon via photosynthesis. Of 21 cyanobacterial strains isolated from pulp and paper waste-treatment systems located in 4 countries, all except one were capable of glucose uptake in the light, and 19 also showed uptake in the dark. In the 6 species tested, glucose and acetate addition stimulated growth in low light in all except one species. Aphanocapsa rivularis grew equally well on glucose and acetate in the dark but Pseudanabaena sp. grew well on acetate, and minimally on glucose. Growth stimulation by glucose and acetate in these two strains was greater in low than in high light. Pseudanabaena sp. and Phormidium animale both accumulated 2,4-dichlorophenol and 3-chlorobenzoate but showed minimal mineralization to CO₂. None of the four species tested could accumulate or degrade phenol or dichloroacetate. It is concluded that, depending on the light conditions, cyanobacteria contribute organic carbon in photosynthesis, and/or remove small organic molecules during mixotrophic and heterotrophic growth but are not important degraders of contaminants in these waste treatment systems.     

FUNCTIONAL ASPECTS OF SECONDARY CAROTENOIDS IN HAEMATOCOCCUS LACUSTRIS (VOLVOCALES). III. ACTION AS A “SUNSHADE”1

We investigated the protection from photoinhibition by different developmental stages of Haematococcus lacustris [Girod] Rostafinski using chlorophyll fluorescence measurements of single cells and suspensions. An overall correlation between higher cellular content of secondary carotenoids and the capacity to withstand excessive irradiation was observed in flagellated cells and aplanospores of H. lacustris. Low-light-reversible spreading of extra-chloroplastic secondary carotenoids occurred in the periphery of the cell during strong irradiation. This process resulted in increased shading of the cup-shaped chloroplast as demonstrated by a decrease in chlorophyll fluorescence. Extrachloroplastic accumulation of secondary carotenoids in H. lacustris can be interpreted as a specific adaptation to habitats that exhibit strong insolation.     

SECONDARY CAROTENOID ACCUMULATION IN SCENEDESMUS KOMAREKII (CHLOROPHYCEAE, CHLOROPHYTA)

As Scenedesmus komarekii Hegewald was cultured under high light intensity and nitrogen limitation, the color of cells progressed from green to brown, and finally through orange to brick red. The secondary carotenoids astaxanthin and canthaxanthin, as well as apolar carotenoids, were detected in the brown and orange cells. These carotenoids were contained in lipoidal globules that were first formed at the periphery of the cell and progressively propagated toward its inside, eventually filling most of it. The chloroplast was single and parietal in the green cells. As the cells turned brown, the chloroplast divided into several small lobes and was pushed toward the interior by the accumulating lipoidal globules. Sometimes the outer layer of the wall of the brown cell developed one or two diametrically opposed swellings. Once the cells became orange or red, neither lipoidal globules nor any major organelles were distinguishable. The cell wall in the orange cells became thick because of the formation of electron-dense granules between its outer and inner layers. The mode of the secondary carotenoid accumulation in S. komarekii differs from that of Haematococcus, an alga well known for its ability to accumulate secondary carotenoids, but resembles that of " Chlorella " zofingiensis (= Mychonastes zofingiensis (Dönz) Kalina et Punčochářová).     

Ecosystem recovery in terra firme forests after cutting and burning: a comparison on species richness, floristic composition and forest structure in the Jaú National Park, Amazonia

Six hectares, three in a primary forest and three in a 40 year old secondary forest were inventoried for all trees with Diameter at Breast Height (DNH) of 10 cm or greater in a terra firme forest 200 km north-east of Manaus, central Amazonia in order to compare the difference between structure, species richness and floristic composition. Both species richness and tree density were significantly higher in the upland forest than in the secondary forest. The forest structure pattern analysed (DBH, basal area and estimated dry biomass) did not differ significantly between the two forest types. Similarity indices at species level were only 14%. In the 3 ha of primary forest the number of species varied from 137 to 159, the number of individuals from 639 to 713, total basal area from 32.8 to 40.2 m² and estimate total of above-ground dry biomass (AGBM) from 405 to 560 tons per ha. In the 3 ha of secondary forest, the number of species varied from 86 to 90, the number of individuals from 611 to 653, total basal area from 28.8 to 39.9 m² and estimated total AGBM from 340 to 586 tons per ha. Family Importance Value (FIV) is the sum of relative density, dominance and richness of a family. The most important families in relation to FIV were Burseraceae, Chrysobalanaceae, Lecythidaceae, Myristicaceae, Bombacaceae, Fabaceae and Mimosaceae in the 3 ha of primary forest, while Burseraceae, Lecythidaceae, Sapotaceae, Arecaceae and Cecropiaceae were the most important families in the 3 ha of secondary forest. Importance Value Index (IVI) is the sum of relative density, dominance and frequency of a species. Alexa grandiflora (Caesalpiniaceae), Sckronema micranthum (Bombacaceae) and Pourouma guianensis (Cecropiaceae) were the most important species in relation IVI, in the primary forest, while Eschweilera grandiflora (Lecythidaceae), Protium apiculatum (Burseraceae) and Bertholletia excelsa (Lecythidaceae) were the most important species in the secondary forest. We conclude that species richness was significandy different between the two forests, but that forest structure patterns analysed in this study (DBH, basal area and dry biomass) were similar. This demonstrates that 40 years was sufficient time for the secondary forest to recover the original structure of the primary forest, but not the original species richness. The low species similarity between the two forests indicates that the floristic composition was quite distinct and that the mixture of primary forest and disturbed forest has led to an increase in total species diversity.     

Secondary Carotenoids of Eremosphaera viridis De Bary (Chlorophyceae) Under Nitrogen Deficiency*

Under nitrogen deficiency the unicellular chlorococcalean green alga, Eremosphaera viridis De Bary, was able to synthesize secondary carotenoids (SC). Nine SC were identified as six astaxanthin esters, echinenone, canthaxanthin and a lutein ester, previously not described in green algae under nitrogen deficiency. These SC, jS-carotene and the main part of lutein were located in lipid bodies outside the chloroplasts in the cytosol. The synthesis of SC could be inhibited by the herbicides norflurazon and nicotine. This result supported the idea that SC in cells ot Eremosphaera viridis were synthesized de novo rather than derived from primary carotenoids.     

Mycotoxin production by different ochratoxigenic <Emphasis Type="Italic">Aspergillus</Emphasis> and <Emphasis Type="Italic">Penicillium</Emphasis> species on coffee- and wheat-based media

Ochratoxin A (OTA) is one of the most widespread mycotoxins, and is produced by several Aspergillus or Penicillium species. Human exposure to OTA is mainly by intake of contaminated food, with cereal products, followed by coffee and red wine as the main sources of OTA. In this study, the OTA production of four ochratoxigenic fungi (two Aspergillus and two Penicillium species) was investigated in four different media, i.e. wheat and coffee model media as food-based media and two standard laboratory media (malt extract glucose agar, MEA and yeast extract sucrose agar, YES). Colony growth was documented and OTA concentrations in cultures were determined at day 2, 4 and 8 of incubation at 25°C by high-performance thin-layer chromatography (HPTLC) and high-performance liquid chromatography (HPLC). OTA production clearly depended upon time of incubation, fungal species, and medium composition. On coffee based medium, moderate OTA levels were produced by A. ochraceus BFE635 (9.8 μg/g) and by A. niger BFE632 (10.6 μg/g) on day 8 of incubation. In wheat-based medium, these strains produced much more OTA than in coffee. The highest OTA concentration (83.8 μg/g on day 8) was formed by A. ochraceus BFE635 followed by the other Aspergillus niger BFE632 (49 μg/g). Lower OTA levels were produced by P. verrucosum BFE550 and P. nordicum BFE487, in both wheat and in YES medium, whilst OTA was hardly detectable in coffee and in MEA in case of P. nordicum. Colony growth of the tested strains on different media was not indicative of OTA production. Guttation droplets developed on wheat-based medium with the Aspergillus strains within a week, and this phenomenon coincided with the high OTA amounts formed by these species. Results from this study add to our knowledge on the behaviour of ochratoxigenic fungal species when cultured on food based media.     

Four new species of yeast isolated from insect frass in bark ofTsuga heterophylla (Raf.) Sargent

Summary In a study of the yeasts associated with insect frass underneath the bark ofTsuga heterophylla (the Pacific Coast hemlock) four new species of yeast were found. These were described asSporobolomyces singularis, Bullera tsugae, Cryptococcus skinneri andCandida oregonensis. Sporobolomyces singularis is a non-pigmented species, which required an amendment of the genus definition. Ballistospore formation of the new species ofSporobolomyces and ofBullera was absent on malt agar and on potato glucose agar, but positive on corn meal agar. An unusual case of quantitative transgalactosylation by growing cells ofSporobolomyces singularis on lactose has been described. It has been proposed to establish a “Candida parapsilosis Group” of species to whichC. oregonensis was assigned. Supported by a fellowship of the Calouste Gulbenkian Foundation, Lisbon, Portugal.     

Wing pigmentation in Calopteryx damselflies: a role in thermoregulation?

Body melanization may show adaptive variation related to thermoregulation ability, and it is to be expected that the degree of melanization will change among populations or closely related species across environmental gradients of solar radiation and/or environmental temperature. Some melanized secondary sexual traits may also play a role in sexual selection, leading to interpopulation variation, which would not be predicted by thermoregulation pressures alone. We studied the relationships between the interpopulation variation in wing pigmentation level (i.e. melanized secondary sexual trait) of two closely related species of Calopteryx damselfly, and both solar radiation and maximum environmental temperature estimates. Wing pigmentation differs between these species, is gender specific and is used in species' discrimination. Only Calopteryx virgo meridionalis males showed a significant negative partial correlation between wing pigmentation degree and temperature. However, C. virgo meridionalis females showed a positive significant partial correlation between wing pigmentation degree and solar radiation. Wing pigmentation in Calopteryx xanthostoma males was not related to solar radiation or temperature. Thus, thermoregulation pressures poorly explained the observed variations in wing pigmentation between populations, although they might have an adaptive significance at the species' level. As wing pigmentation showed important latitudinal variation, several other selection pressures which might act on melanized traits are briefly discussed. © 2011 The Linnean Society of London, Biological Journal of the Linnean Society, 2011, 103 , 36–44.     

Habitat constraints on carotenoid‐based coloration in a small euryhaline teleost

Display of bright and striking color patterns is a widespread way of communication in many animal species. Carotenoid‐based coloration accounts for most of the bright yellow, orange, and red displays in invertebrates, fish, amphibians, reptiles, and birds, being widely considered a signal of individual health. This type of coloration is under the influence of several factors, such as sexual selection, predator pressure, pigment availability, and light transmission. Fish offer numerous examples of visual communication by means of color patterns. We used a small cyprinodontid fish, Aphanius fasciatus (Valenciennes, 1821), as a model species to assess habitat constraints on the color display in male caudal fin. Populations from natural and open/closed artificial habitats were tested for differences in the pigmentation of caudal fins. The most important factors explaining the intensity of coloration were the habitat type and the chlorophyll concentration in the sediment, followed by water turbidity; yellow fins were observed in natural habitats with low chlorophyll concentration and high water turbidity, while orange fins occurred in artificial habitats with high chlorophyll concentration and low turbidity. Furthermore, A. fasciatus in artificial habitats showed a higher somatic and a lower reproductive allotment with respect to natural habitats, according to the existing literature on the species. Furthermore, in closed artificial habitats, where the most intense reddish coloration of caudal fins was observed, a trade‐off between somatic growth and the coloration intensity of a carotenoid‐based sexual ornament has been observed; in these populations, intensity of caudal fin coloration was negatively related to the somatic allotment. Results of this study suggested how both the pigmentation of male's caudal fin and the life history strategies of the species are constrained by habitat characteristics.     

CULTURALLY INDUCED VARIATION IN FOUR MORPHOLOGICALLY DIVERSE BLUEGREEN ALGAE

Characters used in taxonomic placement at levels from family to species appeared, disappeared, or varied widely, while others remained constant, in cultures of four disparate species of blue-green algae (Cyanophyta) under varying conditions of culture. Species of Anabaena and Gloeocapsa displayed fairly stable characteristics. Species of Calothrix and Lyngbya exhibited much greater variability, especially in twisting of filaments, presence or absence of constrictions at the cross walls, abundance of heterocysts, pseudovacuoles, fragmentation of filaments, and change of color. Color change was associated with abrupt pH shift in Lyngbya and could be reversed by adding nitrate. In the putatively nitrogen-fixing Anabaena, similar change in color with age was not associated with sharp pH shift, nor could it be reversed with nitrate. In general, growth on agar in turbulent conditions and with decreased CO₂–O₂ exchange was less than that obtainable under other conditions, and media with acid pH were partially or totally inhibitory to growth.