STUDIES IN THE GENUS CALICIOPSIS

1963 ◽  
Vol 41 (4) ◽  
pp. 503-543 ◽  
Author(s):  
A. Funk
Keyword(s):  
Pure Culture ◽  
Nitrogen Sources ◽  
Developmental Studies ◽  
Extensive Field ◽  
Carbon Compounds ◽  
Effects Of Ph ◽  
Pure Cultures ◽  
Dark Staining ◽  
Host Parasite ◽  
A New Species

Three species of the genus Caliciopsis, all of which produce cankers on conifers, were investigated with respect to development, morphology, general biology, and pathogenicity. Caliciopsis orientalis is described as a new species. Developmental studies have shown that the ascocarps originate from the surface of an erumpent stroma. The female sexual structures are formed from dark-staining hyphae which arise in the core of the young ascocarp. Certain of these hyphae send out trichogynes which penetrate to the outside of the ascocarp. The hyphae enlarge greatly and produce clusters of ascogonia by a budding process or through meristogenous division of the hyphal cells. The ascogonia may further divide by septum formation and thus become multicellular. Septate, branching ascogenous hyphae grow out from the ascogonia and give rise to tufts of asci from the terminal cells. The stalks of the asci elongate enormously as they are carried up into the hymenium. Homologous development and structure were shown in several members of the Caliceaceae. Differences in the final appearance of the hymenium were attributed to the absence of extensive ascogenous hyphae in the Caliceaceae, but the fundamental similarities were interpreted as evidence of a phylogenetic relationship with Caliciopsis. Comparison of the asci, hymenium, and general habit of two genera of the Coryneliaceae with Caliciopsis confirmed the opinion of previous workers that the two groups are related. Observations on fruiting cycles revealed developmental correlations which indicated the possibility of functional spermatia, but experimental spermatization failed to prove this. Data on spore dissemination, germination, and penetration were also gathered. Canker anatomy and host–parasite relationships were elucidated. Pure cultures were obtained from both spermatia and ascospores. The latter were used to determine nutritional requirements of the fungus by measuring growth response to 14 carbon compounds, 5 nitrogen sources, and 7 vitamins. The effects of pH, temperature, and aeration on vegetative growth in pure culture were also studied. Extensive field observations revealed that one species (C. pseudotsugae) is widespread in British Columbia on three native conifers, and that in addition to primary pathogenicity it offers opportunities for associative effects to other forest pathogens which may result in serious damage. Behavior in pure culture confirmed the evidence of association between the pathogens involved. Pathogenicity was proved by extensive field inoculations.

A new species of Hypatima Hübner (Lepidoptera: Gelechiidae) injurious to mango trees in East Africa

1989 ◽  
Vol 79 (3) ◽  
pp. 411-420 ◽  
Author(s):  
K. Sattler ◽  
A. B. Stride
Keyword(s):  
Life History ◽  
New Species ◽  
East Africa ◽  
Female Genitalia ◽  
Field Observations ◽  
Laboratory Studies ◽  
Male And Female ◽  
Extensive Field ◽  
A New Species

AbstractHypatima mangiferae Sattler sp. n. is described from Kenya, where its larva is injurious to commercial mango trees. A description of its life-history, based on extensive field observations and laboratory studies, is also provided. The moth, its male and female genitalia and the damage caused by the larva are illustrated.

scholarly journals A New Phytophthora sp. Causing a Basal Canker on Beech in Italy

Plant Disease ◽  
2003 ◽  
Vol 87 (8) ◽  
pp. 1005-1005 ◽  
Author(s):  
E. Motta ◽  
T. Annesi ◽  
A. Pane ◽  
D. E. L. Cooke ◽  
S. O. Cacciola
Keyword(s):  
New Species ◽  
Central Italy ◽  
European Beech ◽  
Phytophthora Species ◽  
Deciduous Tree ◽  
Reference Isolate ◽  
European Chestnut ◽  
Pure Cultures ◽  
Basal Portion ◽  
A New Species

In autumn 2001, bleeding cankers were observed on the basal portion of the trunk of a declining tree in a forest stand of European beech (Fagus sylvatica L.) in Latium (central Italy). A Phytophthora sp. was isolated consistently from infected trunk bark using whole apples as bait. Isolations were made from brown lesions that developed in the apple pulp around the inserted bark pieces. Pure cultures were obtained by using hyphal tip transfers. Colonies were stellate on V8 juice agar (V8A), uniform to slightly radiate on cornmeal agar, and cottony, without a distinct growth pattern on potato dextrose agar (PDA). On V8A, radial growth rates were 2.1, 4.8, and 4.5 mm/day at 10, 15, and 20°C, respectively. Colonies grew slowly at 5 and 25°C, but failed to grow at 30°C. On PDA, growth was 1.7 and 1.4 mm/day at 15 and 20°C, respectively. Catenulate hyphal swellings formed on solid and liquid media. Sporangia formed abundantly at 15°C, were ovoid to obpyriform, semipapillate, occasionally bipapillate, and had narrow exit pores (mean diameter = 5.4 μm). On V8A, pores were 40 to 50 μm in length and 25 to 40 μm in breadth. Isolates were homothallic with paragynous antheridia, oogonia were spherical with diameters from 32 to 35 μm, and oospores were plerotic with diameters from 20 to 30 μm. Electrophoretic banding patterns of mycelial proteins and isozymes (alkaline phospatase, esterase, glucose-6-phospate dehydrogenase, malate dehydrogenase, and superoxide dismutase) of beech isolates were distinct from those of reference isolates of semipapillate Phytophthora species, including P. citricola, P. hibernalis, P. ilicis (IMI 158964), P. psychrophila (CBS 803.95), and P. syringae from citrus fruits, whose identification had been confirmed on the basis of internal transcribed spacer (ITS)-restriction fragment length polymorphism (RFLP) patterns and sequences. Conversely, the electrophoretic phenotype and the ITS-RFLP pattern (and sequence) of the beech isolates were identical to those of a reference isolate (Ph24) from Quercus cerris, which was originally identified as P. syringae on the basis of morphological and cultural characters (1). However, the isolate Ph24 has been reexamined, and morphological and cultural characteristics as well as the ITS sequence would indicate that this isolate is a new species not yet formally described, for which the name P. pseudosyringae has been suggested (2). The pathogenicity of a beech isolate (IMI 390500) was compared to that of an Italian P. cambivora isolate from European chestnut by inoculating the stems of 16-month-old beech seedlings (10 replicates), which were placed at 18°C with a 12-h photoperiod. The beech isolate produced lesions averaging 2 cm long after 2 months, while those produced by the P. cambivora isolate averaged 3 cm. Control seedlings inoculated with sterile agar did not develop symptoms. The pathogen was reisolated from lesions to fulfil Koch's postulates. To our knowledge, this is the first report of this new Phytophthora sp. on beech in Italy. Conversely, the same species has been reported to be associated with decline of oak stands (1). References: (1) G. P. Barzanti et al. Phytopathol. Mediterr. 40:149, 2001. (2) T. Jung et al. Phytophthora pseudosyringae sp. nov., a new species causing root and collar rot of deciduous tree species in Europe. Mycol. Res. (In press).

EFFECTS OF pH AND NITROGEN SOURCES ON GROWTH OF MICROCYSTIS AERUGINOSA KÜTZ.

1962 ◽  
Vol 8 (1) ◽  
pp. 1-11 ◽  
Author(s):  
Jack McLachlan ◽  
P. R. Gorham
Keyword(s):  
Growth Inhibition ◽  
Microcystis Aeruginosa ◽  
Nitrate Nitrogen ◽  
Nitrogen Sources ◽  
Cesium Chloride ◽  
Potassium Nitrate ◽  
Degree Of Ionization ◽  
Ph Values ◽  
Effects Of Ph ◽  
Ph Range

Microcystis aeruginosa Kütz. (strain NRC-1) grew equally well throughout the pH range 6.5 to 10 when provided with suitable media. Toxicity of tris(hydroxymethyl)aminomethane (TRIS) towards the alga was found to decrease as the pH decreased and could be correlated with the degree of ionization of the TRIS molecule. Other organic buffers examined were either toxic at all concentrations and pH values tested or promoted lysis. When TRIS was used as a buffer, higher concentrations of cesium chloride and potassium nitrate were tolerated without growth inhibition at pH 6.5 than at 7.5. In the presence of TRIS, Microcystis grew equally well with nitrate, ammonium, or urea as nitrogen sources. Eight out of 20 amino compounds examined served as nitrogen sources in TRIS-buffered medium, but growth was poorer than with nitrate nitrogen.

Effect of Enrichment Media and Sampling Protocol on Recovery of Listeria monocytogenes

1990 ◽  
Vol 53 (6) ◽  
pp. 505-507 ◽  
Author(s):  
J. S. BAILEY ◽  
D. L. FLETCHER ◽  
N. A. COX
Keyword(s):  
Listeria Monocytogenes ◽  
Pure Culture ◽  
Sampling Protocol ◽  
Enrichment Broth ◽  
Secondary Enrichment ◽  
Pure Cultures ◽  
University Of Vermont

These studies examined the differences in recovery of Listeria monocytogenes from pure culture and in the populations of mixed aerobic microflora from chicken and Brie cheese incubated in University of Vermont (UVM) and Listeria enrichment broth (LEB) enrichment broths for different times and conditions. No significant differences were observed in levels of L. monocytogenes from pure cultures in UVM or LEB on any sampling day. No differences were observed in the levels of mixed microflora from Brie cheese in either UVM or LEB, but from chicken rinse the level of mixed flora competitors was significantly higher on all sampling days in LEB as compared to UVM. No differences were observed between a single enrichment in UVM or LEB for 2 d and a transfer to a secondary enrichment tube after 1 d. Overall, the level of mixed microflora capable of growing in enrichment broths was greater from chicken rinse than from Brie cheese. The ratio of L. monocytogenes to mixed microflora which survived the selective enrichments was most favorable for recovery of L. monocytogenes after 2 d of enrichment.

A new feather mite species of the genus Neumannella Trouessart, 1916 (Analgoidea, Dermoglyphidae) from the Red-winged Tinamou Rhynchotus rufescens (Temminck, 1815) (Aves, Tinamiformes) with remarks to the evolution of host-parasite associations of the genus

2014 ◽  
Vol 59 (2) ◽  
Author(s):  
Jacek Dabert
Keyword(s):  
New Species ◽  
Evolutionary History ◽  
Morphological Characters ◽  
Mite Species ◽  
Feather Mite ◽  
History Of ◽  
Host Parasite ◽  
Reconciliation Method ◽  
A New Species ◽  
Mite Family

AbstractNeumannella skorackii, a new species of the feather mite family Dermoglyphidae (Acari, Astigmata) is described from the Red-winged Tinamou Rhynchotus rufescens (Temminck, 1815) (Aves, Tinamiformes) from Paraguay and a key to all known species of the genus is provided. The phylogenetic relationships (MP analysis of 25 morphological characters) between Neumannella species along with the evolutionary history of host-parasite associations revealed by Jungle reconciliation method are reconstructed. Relatively low cospeciation contribution to the recent host-parasite associations is discovered.

Taxonomic Studies on Australian Isolates of Stemphylium spp. And Associated Teleomorphs

1986 ◽  
Vol 34 (3) ◽  
pp. 281 ◽  
Author(s):  
JAG Irwin ◽  
R Dill-Macky ◽  
M Stirling
Keyword(s):  
Medicago Sativa ◽  
Pure Culture ◽  
Herbarium Specimens ◽  
Simmondsia Chinensis ◽  
Pure Cultures ◽  
Taxonomic Studies ◽  
Ascospore Morphology

Taxonomic studies on monosporic pure cultures of Australian isolates of Stemphylium revealed the presence of three species, namely S. botryosum, S. globuliferum and S. vesicarium. A group intermedi- ate between S. botryosum and S. vesicarium but more closely resembling S. vesicarium was recognised. The circumscription of S. vesicarium was broadened to accommodate this taxon which was found on Medicago sativa, M. rugosa and Simmondsia chinensis. Studies on herbarium specimens deposited as S. botryosum on M. sativa from a number of overseas locations indicated that in all cases the pathogen fitted our concept of S. vesicarium. Teleomorphs were induced in pure culture for each of the above-mentioned anamorphs, and in all instances the teleomorph was identified as Pleospora herbarum. The ascospore morphology was similar for all isolates, and the shape of the ends of the spore and the number of longitudinal septa were variable characters even within an isolate. However, the teleomorphs could be separated into two distinct groups on the basis of ascal length.

Description of a new marine planktonic cyanobacterial species Synechococcus moorigangaii (Order Chroococcales) from Sundarbans mangrove ecosystem

Phytotaxa ◽  
2019 ◽  
Vol 393 (3) ◽  
pp. 263 ◽  
Author(s):  
TARKESHWAR SINGH ◽  
PUNYASLOKE BHADURY
Keyword(s):  
New Species ◽  
16S Rrna ◽  
Model Organism ◽  
Nitrogen Sources ◽  
Mangrove Ecosystem ◽  
Fatty Acid Analysis ◽  
Ammonium Ion ◽  
Cyanobacterial Species ◽  
Rrna Phylogeny ◽  
A New Species

The genus Synechococcus is widespread across marine environments globally including in coastal habitats. In this study, culture of a new isolate (CMS01) of Synechococcus has been established and described based on polyphasic taxonomy from the world’s largest mangrove ecosystem, Sundarbans. This planktonic photoautrotroph has been proposed as a new species Synechococcus moorigangaii sp. nov. belonging to the order Chroococcales. The cells representing this proposed new species are solitary and can also form chain comprising of 4–6 cells. The shape of cell is oval to cylindrical and length ranges from 1.2–3 µm while the width ranges from 0.8–2 µm. The distribution pattern of photosynthetic filaments was found to be from the periphery of cell. Based on robust phylogeny of 16S rRNA, in addition to functional genes such as psbA, ureC, rbcL, and cbbA (multi gene phylogeny), the proposed new species differed from closest described species of Synechococcus under order Chroococcales. The fatty acid analysis indicated the presence of C12 and C14 chain fatty acids exclusive to isolate CMS01. The new isolate can grow across a range of salinity and in presence of different nitrogen sources. It has the ability to fix atmospheric di-nitrogen into ammonium ion. This new isolate of Synechococcus spp. is the first marine planktonic cyanobacterium described from a mangrove ecosystem and characterized using polyphasic approaches. Based on 16S rRNA phylogeny, this proposed new species clustered with Synechococcus strains PCC 7117, PCC 73109, PCC 7002, PCC 7003, PCC 7376 and NKNG15041c belonging to the order Chroococcales. The new species Synechococcus moorigangaii sp. nov. can serve as a model organism to understand ecophysiology and adaptation of planktonic cyanobacterial communities in mangrove ecosystems.

THE PHYSIOLOGY OF HOST–PARASITE RELATIONS: I. THE ACCUMULATION OF RADIOACTIVE SUBSTANCES AT INFECTIONS OF FACULTATIVE AND OBLIGATE PARASITES INCLUDING TOBACCO MOSAIC VIRUS

1956 ◽  
Vol 34 (3) ◽  
pp. 389-405 ◽  
Author(s):  
Michael Shaw ◽  
D. J. Samborski
Keyword(s):  
Carbon Dioxide ◽  
Tobacco Mosaic Virus ◽  
Mosaic Virus ◽  
High Rate ◽  
Fungal Mycelium ◽  
Obligate Parasites ◽  
Tracer Techniques ◽  
Metabolic Products ◽  
Carbon Compounds ◽  
Host Parasite

Excised, parasitized leaves were placed with their bases in radioactive solutions or exposed to radioactive carbon dioxide and the uptake and distribution of the tracers followed by autoradiography. Carbon dioxide and 20 other carbon compounds, including sugars, amino and organic acids, phenols, and indoleacetic acid, and/or their metabolic products, as well as phosphate and calcium, accumulated strongly at uredial and conidial colonies of the obligate parasites Puccinia and Erysiphe, respectively. Accumulation of glucose occurred in the host tissue at the sites of mildew colonies on leaves from which the ectoparasitic fungal mycelium had been removed, paralleled the respiration, rate, increased progressively with the development of the parasites, and was most marked at type 4 infections. It was inhibited by sulphur dust (with mildew), sodium azide, 2,4-dinitrophenol and, reversibly, by anaerobiosis and was, therefore, dependent on aerobic respiration. On the other hand the tracers did not accumulate within senescent rust and mildew colonies or within the necrotic lesions produced by bacterial and fungal parasites which kill the tissues of their hosts. Radioactive glucose did not, but calcium and phosphate did, accumulate within young local lesions of tobacco mosaic virus on Nicotiana. The tracers did not enter dead areas on mechanically-wounded leaves and only accumulated at fresh wounds under conditions conducive to a high rate of water loss from the damaged surface. In conjunction with more conventional methods, tracer techniques provide a powerful method of attack on the problems of host–parasite relationships.

The ecology and genetics of fitness in Chlamydomonas . II. The properties of mixtures of strains

1990 ◽  
Vol 240 (1298) ◽  
pp. 323-350 ◽  
Keyword(s):  
Pure Culture ◽  
General Tendency ◽  
Average Effect ◽  
Physical Environments ◽  
Unicellular Green Alga ◽  
Excess Production ◽  
Pure Cultures ◽  
Predictor Of Success ◽  
Genotype Interaction ◽  
Series Of Experiments

Whether or not mixtures of strains possess special properties depends on whether or not their component genotypes interact with one another. This paper describes a series of experiments designed to investigate genotype-by-genotype interaction among species of the unicellular green alga Chlamydomonas when grown axenically as liquid cultures in chemically defined media. It was shown that strains varied substantially in their average effect on the overall production of mixed cultures, and that specific interactions between pairs of genotypes were also significant, though small. This conclusion was confirmed by experiments in which strains were cultured separately in growth medium that had been con­ditioned by the prior culture of another strain. However, there was no consistent general tendency for mixtures to be more productive than the average of their components in pure culture; some mixtures in some physical environments were markedly more productive than their com­ponent means, but other mixtures in other environments were markedly less productive. The average effect of a strain on the production of mixtures was uncorrelated with its performance in pure culture, showing that fitness measured in pure culture may be a poor predictor of success in mixed populations. However, the average effect of a strain in simple mixtures was correlated with its effect in more complex mixtures. Com­plex mixtures themselves displayed properties similar to, but more extreme than, those of simple mixtures; thus, in an environment where pairwise mixtures tended to outyield pure cultures, excess production tended to increase with mixture complexity. The results of these experiments seem to be consistent with those of comparable agronomic trials.

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