The mycology of the freeliving baboon (Papio sp.)

Summary Three field trips were conducted to study the mycoflora of the baboon in its native habitat, East Africa. The flora of the throat, nose, ear, rectum, vagina, and skin of over 300 male and female baboons was studied. A total of 1102 yeast isolates was obtained. None of the molds isolated were of known significant pathogenicity, while yeast isolates were found to belong to the following major genera:Candida, Cryptococcus, Rhodotorula, Saccharomyces, Torulopsis, andTrichosporon. Candida albicans was found to be the yeast most frequently isolated in both 1964 and 1966, while species ofRhodotorula andCryptococcus were more frequently found in 1968. It is our belief that various ecological and geographical conditions have an effect on the mycoflora of the animals, specifically from the quantitative point of view.     

The distribution of peanut fungi in the Southeastern United States

During a four-year survey in Alabama, Georgia, North Carolina, Oklahoma, Texas and Virginia of the fungi associated with peanut shells and seeds 70 genera and 146 species of fungi were identified. Twenty-seven genera and 60 species were isolated from peanut fruits for the first time. Nine genera are Phycomycetes, 17 are Ascomycetes, and 44 are Deuteromycetes. A total of 110 genera and about 200 species of fungi have now been reported from peanuts. A key to the genera reported in this study is included, along with the distribution by state for each species.Journal Series Paper No. 1066, University of Georgia College of Agriculture Experiment Stations, College Station, Athens. This work was supported in part by funds under Cooperative Agreement No. 12-14-100-9378 (34), administered by Crops Research Division, Agricultural Research Service, U. S. Department of Agriculture.     

Yeasts associated with pods and exudates of algarrobo trees (Prosopis spp.) and species of columnar cacti in northwest Argentina

Yeasts were isolated from exudates of algarrobo trees from nine sites in northwest Argentina, three in the Chaco region, from pods of algarrobo and acacia, collected in the Quebrada de Cafayate, and from rot pockets in decaying columnar cacti at Cachi (Parc Nacional des Cardons), and at Las Ruinas de Quilmes. Most of the yeasts isolated from exudates of algarrobo were identified asBullera variabilis, Candida famata, Cryptococcus albidus and otherCryptococcus species,Debaryomyces hansenii, Pichia angusta (Hansenula polymorpha),Pichia ciferrii, Pichia farinosa andTorulaspora delbrueckii. OtherCandida, Kluyveromyces andPichia species were found. Most species were osmotolerant. The high sugar content of the exudates influenced the nature of the yeast species present. The pods containedCryptococcus spp.,Candida famata andCandida ciferrii spp. Half the species isolated from rotting cactus wereCryptococcus species.Pichia membranaefaciens andTorulaspora delbrueckii were also isolated. Of 553 cultures investigated, 49 utilized methanol.Deceased on July 24th, 1995     

Studies on fungi associated with tomato fruits and effectiveness of some commercial fungicides against three pathogens

Among 39 fungal species and one variety belonging to 16 genera isolated from 116 healthy tomato fruits collected from markets in Assiut, Egypt, during 1994,Aspergillus niger was found to be the most prevalent, being isolated from 84.6% of the samples. Of 11 species recovered from 156 diseased tomatoes,Alternaria alternata, Rhizopus stolonifer andA. niger were the most common and isolated from 52.7%, 35.9% and 25.0% of the samples, respectively. Experiments for comparison of the effects of medium containing tomato juice with synthetic medium on the mycelial growth of nine fungal species indicated that, the tomato juice medium was more suitable for growth of all fungal species. The effect of five commercial fungicides and sodium hypochlorite when applied as post-harvest dips after inoculation was studied in laboratory againstA. alternata, A. niger andR. stolonifer. At 10 and 100 µg ml^–1, neither of the fungicide caused a noticeable inhibition ofAlternaria rot. At 1000 µg ml^–1 benlate, rovral and sumisclex completely preventedAlternaria andAspergillus rot, whereas cuprosan and ridomil were ineffective against rotting caused byA. niger. Rhizopus rot development was inhibited by over 50% with one treatment only (rovral at 1000 µg ml^–1). Sodium hypochlorite has good curative properties against fruit rots especially those caused byA. alternata andA. niger.     

The mycoflora of peanuts in Egypt

Twenty-six genera and Sixty-six species, in addition to two varieties of Aspergillus nidulans and one variety of Humicola grisea were isolated from 80 peanut seed (uncovered or covered within shell at the time of sampling) samples and 40 samples of shells collected from different places in Egypt.At 28 °C, the broadest spectrum of genera and species was recorded in the shells (21 genera and 53 species), followed by the naked seeds (16 genera and 38 species) and the covered seeds (17 genera and 33 species). Aspergillus and Penicillium were regularly the most common genera in the three substrates. A. niger, A. fumigatus, A. flavus A. terreus, A. ochraceus and P. funiculosum were generally the most common fungal species recovered from the three substrates. A. flavus was represented in 80%, 60% and 80% of the samples constituting 16.1%, 8.4% and 27.2% of the total count of fungi of the shells, covered and uncovered seeds respectively.At 45 °C, nine genera and sixteen species were collected of which Aspergillus fumigatus was extremely dominant in the three substrates, followed by A. terreus and A. niger. Penicillium was completely eliminated.     

Purified moniliformin does not affect the force or rate of contraction of isolated guinea pig atria

Aspergillus flavus Link ex Fries and A. parasiticus Speare can invade peanut kernels and under certain environmental conditions produce unacceptable levels of the mycotoxin aflatoxin. A concerted effort is underway to reduce aflatoxin contamination in peanut and peanut products. A potentially effective method of control in peanut is the discovery and use of genes for resistance to either fungal invasion or aflatoxin formation. The objective of the present experimental study was to develop an effective and efficient procedure for screening individual plants or pods of single plants for resistance to invasion by the aflatoxigenic fungi and subsequent aflatoxin production. Methods of obtaining adequate drought-stress and fungal infection were developed through this series of experiments. By completely isolating the pods from the root zone and imposing drought-stress only on pegs and pods, high levels of fungal infection were observed. High amounts of preharvest aflatoxin accumulation were also produced by completely isolating the pods from the root zone. Mid-bloom inoculation with A. parasiticus-contaminated cracked corn and drought-stress periods of 40 to 60 days were the most effective procedures. This technique was used to assess peanut genotypes previously identified as being partially resistant to A. parasiticus infection or aflatoxin contamination, and segregating populations from four crosses. Variability in aflatoxin contamination was found among the 11 genotypes evaluated, however, none were significantly lower than the standard cultivars. Broad-sense heritability of four crosses was estimated through evaluation of seed from individual plants in the F₂ generation. The heritability estimates of crosses GFA-2 × NC-V11 and Tifton-8 × NC-V11 were 0.46 and 0.29, respectively, but mean aflatoxin contamination levels were high (73,295 and 27,305 ppb). This greenhouse screening method could be an effective tool when genes for superior aflatoxin resistance are identified.Cooperative investigation of the USDA-ARS and the University of Georgia, College of Agriculture.     

Evaluation of selected geocarposphere bacteria for biological control of Aspergillus flavus in peanut

Selected bacterial strains isolated from the region of peanut pod development (geocarposphere) and two additional bacterial strains were screened as potential biological control agents against Aspergillus flavus invasion and subsequent aflatoxin contamination of peanut in laboratory, greenhouse, and field trials. All 17 geocarposphere strains tested delayed invasion of young roots and reduced colonization by the fungus in a root-radicle assay used as a rapid laboratory prescreen. In a greenhouse study, seven bacterial strains significantly reduced pod colonization by A. flavus compared to the control. In a field trial, conducted similarly to the greenhouse assay, pods sampled at mid-peg from plants seed-treated with suspensions of either 91A-539 or 91A-550 were not colonized by A. flavus, and the incidence of pods invaded from plants treated with either 91A-539 or 91A-599 was consistently lower than nonbacterized plants at each of five sampling dates. At harvest, 8 geocarposphere bacterial strains significantly lowered the percentage of pods colonized (> 51%) compared to the control. Levels of seed colonization ranged from 1.3% to 45% and did not appear related to aflatoxin concentrations in the kernels.     

Contribution of the mesophilic fungi of different spices in Egypt

Thirty-eight genera and 81 species of fungi were isolated and identified from 120 samples of 24 kinds of spices collected from different places at Assiut Governorate, Egypt. Predominant genera wereAspergillus (25 species) andPenicillium (7 species) of whichA. flavus, A. niger, A. ochraceus, A. fumigatus, A. flavus var.columnaris, A. terreus, P. chrysogenum andP. corylophilum were the most commonly occurring.     

Mycotoxin-producing potential of fungi associated with qat (Catha edulis) leaves in yemen

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.     

Distribution of fungi on two mite species and their habitats in Egypt

Fungi associated with two mite species,Acotyledon krameri andTyrophagus putrescentiœ, and their habitats were studied using 1% glucose-Czapek's and potato-dextrose agar media at 28±2°C. A total of 54 species and one variety belonging to 25 genera were recovered from different habitats of mite species; 36 species and one variety belonging to 18 genera were associated with mite bodies. Nearly most fungal species isolated from mite bodies were also encountered in their habitats. The most common species wereAspergillus flavus, A. fumigatus, A. niger, Mucor racemosus, Nectria hœmatococca. A. terreus, Scopulariopsis brevicaulis andTrichurus spiralis were isolated only from mite bodies whereasFusarium oxysporum, Penicillium chrysogenum, P. corylophilum, P. funiculosum andRhizopus stolonifer were recovered from the mite habitats.A. krameri individuals survived well onCunninghamella elegans, F. oxysporum andM. racemosus cultured on both type of media, whereasCylindrocarpon destructans was best forT. putrescentiœ survival.     

Mould biodiversity in homes I. Air and surface analysis of 130 dwellings

Summary Air and surface sampling to quantify and identify fungi were conducted over a 10-year period in 130 Belgian homes, including flats and houses. Homes were selected based on the medical files of allergic, mostly asthmatic patients to assess possible mould responsibility in the aetiology of the disease. Air sampling was done with Reuter centrifugal air sampler using different sampling times and incubation temperatures to detect mesophilic and thermotolerant or thermophilic fungi. More than 50 genera were detected, withCladosporium, Penicillium andAspergillus being the most common. The main species detected wereAspergillus versicolor, several species ofPenicillium, Cladosporium sphaerospermum andCladosporium herbarum. Surface sampling was conducted concomitant with air sampling. Surfaces with and without visible mould growth were tested equally by Rodac contact plates or swabs. AlthoughCladosporium herbarum was shown to be a common species in indoor environments by air sampling, it was not detected by surface sampling from visible mould growth. This finding suggests that its presence in dwellings is from an outdoor origin and not indicative of indoor proliferation.Aspergillus versicolor, Cladosporium sphaerospermun, andPenicillium chrysogenum were the most common species isolated from surfaces showing visible mould growth.     

Effect ofAspergillus parasiticus soil inoculum on invasion of peanut seeds

Environmental control plots adjusted to late season drought and elevated soil temperatures where inoculated at peanut planting with low and high levels of conidia, sclerotia, and mycelium from a brown conidial mutant ofAspergillus parasiticus. Percentage infection of peanut seeds from undamaged pods was greatest for the subplot containing the high sclerotial inoculum (15/cm² soil surface). Sclerotia did not germinate sporogenically and may have invaded seeds through mycelium. In contrast, the mycelial inoculum (colonized peanut seed particles) released large numbers of conidia into soil. Soil conidial populations of brownA. parasiticus from treatments with conidia and mycelium were positively correlated with the incidence of seed infection in undamaged pods. The ratio ofA. flavus to wild-typeA. parasiticus in soil shifted from 7:3 to 1:1 in the uninoculated subplot after instigation of drought, whereas in all subplots treated with brownA. parasiticus, the ratio of the two species became approximately 8:2. Despite high levels of brownA. parasiticus populations in soil, nativeA. flavus often dominated peanut seeds, suggesting that it is a more aggressive species. Sclerotia of wild-typeA. parasiticus formed infrequently on preharvest peanut seeds from insect-damaged pods.     

Peanut Chlorotic Ringspot Virus (PCRV), a Newly Discovered Virus Infecting Peanut (Arachis hypogaea L.)

A virus causing wide chlorotic ringspot (PCRV) associated with chlorotic line pattern and motthng on an Erictoides hybrid growing in USDA-OSU greenhouses, Stillwater, Oklahoma, was discovered. The virus was isolated and characterized and found to differ in symptomology, host range and serological properties from all the previously described viruses infecting peanut, particularly those reported in the United States to be the most important ones, peanut mottle virus, peanut stripe virus, and tomato spotted wilt virus. The virus was transmitted by both mechanical inoctilation and grafting to fourteen peanut cultivars causing identical symptoms to those originally observed on the Erictoides hybrid. In addition to peanut, the virus systemically infected Pisum sativum L. ‘Little marvel’ causing mainly mosaic and Lupinus albus L. ‘Tiftwhite’ producing severe malformation and remarkable reduction in leaflet area. The virus did not infect many other plant species of which cowpea ‘California blackeye’ (Vigna unguiculata L.) and at least five cultivars of soybean (Glydne max L.) are known to be susceptible hosts to peanut mottle virus. Phaseolus vulgaris L. ‘Topcrop’ and Chenopodium amaranticohr Coste & Reyn were found to be two useful local lesion assay and diagnostic hosts for PCRV. The virus elicited necrotic local lesions on the first and chlorotic ringspots on the second. PCRV had a dilution end point between 10^?5 and 10^?6, thermal inactivation point between 55°C and 60°C, and longevity in vitro up to 6 days but not 7 days. Virus particles viewed hy electron microscopy and the negative stain uranyl aceute were flexuous filamentous particles ranging in length from 750–850 nm. In both indiren PAS-ELISA and Ouchterlony double immunodiffusion test, PCRV was serologically related to a PMV isolate from Oklahoma (PMV-OK.) but not to bean yellow mosaic virus, peanut stripe virus, potato virus Y, watermelon mosaic virus 1, watermelon mosaic virus 2, wheat streak mosaic virus, and zucchini yellow mosaic virus.     

Comparative identification by fatty acid analysis of soil,rhizosphere, and geocarposphere bacteria of peanut (Arachis hypogaea L.)

Bacterial isolates were collected from the geocarposphere, rhizosphere, and root-free soil of field grown peanut (Arachis hypogaea L.) at three sample dates, and the isolates were identified by analysis of fatty acid methyl-esters to determine if qualitative differences exist among the bacterial microflora of these zones. Five bacterial genera were associated with isolates from soil, while pod and root isolates constituted 16 and 13 genera, respectively, indicating that bacterial diversity was higher in the rhizosphere and geocarposphere than in soil. The dominant (most frequently identified) genus across all three samples dates was Flavobacterium, for pods, Pseudomonas for roots, and Bacillus, for root-free soil. Sixteen bacterial taxa were only isolated from the geocarposphere, 7 only from the rhizosphere, and 5 only from soil. These results show that specific bacterial taxa are preferentially adapted to colonization of the geocarposphere and suggest that the soil, rhizosphere, and geocarposphere constitute three distinct ecological niches. Bacteria which colonize the geocarposphere should be examined as potential biological control agents for pod-invading fungi such as the toxigenic strains of Aspergillus flavus and A. parasiticus.     

Occurrence of fungal endophytes in cultivars ofTriticum aestivum in South Africa

Fungal endophytes were isolated from leaves, roots and stems of four wheat cultivars and a breeding line at three different sampling dates during the 1993 growing season. Of the 55 different fungal taxa encountered, 19 were present at relative importance values of more than 5%. No cultivar-related differences in the assembleges of endophytes were observed.Phoma glomerata was not restricted to only one tissue type, whereasAlternaria alternata, basidiomycete sp. 1,Pleospora herbarum andEpicoccum nigrum occurred primarily in the leaves, andFusarium avenaceum was extremely frequent in roots. In general, colonization by endophytes increased with the age of the plants. Most endophytes were isolated from wheat leaves. Successional colonization of a given tissue type was quantitative rather than qualitative, with a given fungal taxon increasing or decreasing over the period sampled, rather than replacing the fungi initially encountered.Present address: Téra d'Sott 5, CH-6949, Comano, Switzerland.     

Peanut-pod mycoflora and kernel infection

Summary The mycoflora in soil clinging to dry pods of peanuts of the Spanish variety Argentine was sampled in 2 experiments by serially washing pods for increasing periods in changes of sterile water. Of the 9 principal fungi found,Aspergillus niger, A. flavus, A. terreus, Rhizopus spp. andSclerotium bataticola were present initially in relatively small numbers and decreased rapidly in subsequent dilutions. This decrease paralleled a decrease in weight of suspended material and in percentage of soil and organic particles greater than 0.016 mm in size.Penicillium funiculosum, P. rubrum, P. citrinum, andFusarium spp. were found in large numbers and increased or slowly decreased in numbers in subsequent dilutions. In some instances variations in numbers followed trends of percentages of soil and organic particles less than 0.016 mm in size.When dry pods with this known mycoflora were allowed to hydrate over a 6-day period at 26°, 32°, or 38°C, there was extensive pod penetration and kernel infection byA. niger, A. flavus, S. bataticola andRhizopus spp. but not by other fungi. The degree ofA. flavus andA. niger infection increased with increasing temperatures.Approved by the Director as Journal Series Paper No. 135.     

The systematic significance of morphological and anatomical variation in fruits of Crotalaria and related genera of tribe Crotalarieae (Fabaceae)

The phylogenetic and taxonomic significance of morphological and anatomical trends in fruits of tribe Crotalarieae has been evaluated, with emphasis on the genus Crotalaria and its seemingly distinctive, inflated and balloon‐shaped pods. In addition to the normal explosive dehiscence as a means of dispersal, several genera (including Crotalaria) show independent evolution of modifications apparently adapted for dispersal by wind, water and gravity. Transverse sections were made of mature pods of 142 species from the 12 currently recognized genera of Crotalarieae. The taxa differ in the orientation of the fibres (related to dehiscence or non‐dehiscence), the overall thickness of the fruit wall, the relative proportions of the pericarp layers, the degree of lignification and the presence or absence of trichomes. Three basic pericarp types can be distinguished: type I, with one, two or three zones of various numbers of cell layers of fibres (almost all genera); type II, with a single cell layer of fibres (only in Rothia, Robynsiophyton, Lebeckia and Lotononis sections Listia and Leobordea); and type III, with one zone of several cell layers of gelatinous fibres and multicellular trichomes associated with the endocarp (only in some species of Calobota and Wiborgiella). Considerable variation was encountered in the tribe, but Crotalaria appears to be rather uniform, with type I predominating. © 2010 The Linnean Society of London, Botanical Journal of the Linnean Society, 2011, 165 , 84–106.     

Use of single-primer DNA amplifications in genetic studies of peanut (Arachis hypogaea L.)

A recent approach to detecting genetic polymorphism involves the amplification of genomic DNA using single primers of arbitrary sequence. When separated electrophoretically in agarose gels, the amplification products give banding patterns that can be scored for genetic variation. The objective of this research was to apply these techniques to cultivated peanut (Arachis hypogaea L.) and related wild species to determine whether such an approach would be feasible for the construction of a genetic linkage map in peanut or for systematic studies of the genus. Two peanut cultivars, 25 unadapted germplasm lines of A. hypogaea, the wild allotetraploid progenitor of cultivated peanut (A. monticola), A. glabrata (a tetraploid species from section Rhizomatosae), and 29 diploid wild species of Arachis were evaluated for variability using primers of arbitrary sequence to amplify segments of genomic DNA. No variation in banding pattern was observed among the cultivars and germplasm lines of A. hypogaea, whereas the wild Arachis species were uniquely identified with most primers tested. Bands were scored (+/–) in the wild species and the PAUP computer program for phylogenetic analysis and the HyperRFLP program for genetic distance analysis were used to generate dendrograms showing genetic relationships among the diploid Arachis species evaluated. The two analyses produced nearly identical dendrograms of species relationships. In addition, approximately 100 F₂ progeny from each of two interspecific crosses were evaluated for segregation of banding patterns. Although normal segregation was observed among the F₂ progeny from both crosses, banding patterns were quite complex and undesirable for use in genetic mapping. The dominant behavior of the markers prevented the differentiation of heterozygotes from homozygotes with certainty, limiting the usefulness of arbitrary primer amplification products as markers in the construction of a genetic linkage map in peanut.     

Karyomorphological parameters and C-band distribution suggest phyletic relationships within the subtribeLimodorinae (Orchidaceae)

Karyotype attributes and heterochromatin distribution were used to characterize fourteen taxa of the subtribeLimodorinae (Orchidaceae). The karyotypes were established using morphometrical parameters following Feulgen staining and C-banding. No significant differences in heterochromatin content were found between specimens collected from various sites. Four species of theEpipactis helleborine group possess some chromosome pairs with quite similar heterochromatin patterns; some differences were found inE. distans with respect to other species of this group.Epipactis palustris differed significantly from otherEpipactis species in its different karyotype and its numerous terminal C-bands. The largest differences from the other genera were shown inLimodorum as far as karyomorphology and heterochromatin patterns were concerned. C-band distribution indicated similarity among non-homologous chromosomes, supporting a possible palaeo-polyploid origin for theCephalanthera andEpipactis karyotypes.     

Assessment of mycoflora and infestation of insects,vector of <Emphasis Type="Italic">Aspergillus</Emphasis> section <Emphasis Type="Italic">Flavi</Emphasis>, in stored peanut from Argentina

The occurrence of spoilage fungi and Aspergillus section Flavi populations, the aflatoxins incidence, the role of insects as vectors of mycotoxin-producing fungi and the AFs-producing ability of the isolated species throughout the peanut (Arachis hypogaea L.) storage period were evaluated. Analyses of fungal populations from 95 peanut seed samples did not demonstrate significant differences between the incidences in each sampling period. Aspergillus section Flavi were isolated during all incubation periods. Cryptolestes spp. (Coleoptera: Cucujidae) were collected in August, September and October with 18, 16 and 28% of peanut samples contaminated, respectively. Insects isolated during August showed 69% of Aspergillus section Flavi contamination. A. flavus was the most frequently isolated (79%) from peanut seeds and from insect (59%). The greater levels of AFB₁ were detected in September and October with a mean of 68.86 μg/kg and 69.12 μg/kg respectively. The highest proportion of A. flavus toxigenic strains (87.5%) was obtained in June. The presence of Aspergillus section Flavi and insect vectors of aflatoxigenic fungi presented a potential risk for aflatoxin production during the peanut storage period. Integrated management of fungi and insect vectors is in progress.