Behavior of Fusarium roseum 'Sambucinum' under carbon starvation conditions in relation to survival in soil

1969 ◽  
Vol 15 (1) ◽  
pp. 117-126 ◽  
Author(s):  
G. J. Griffin ◽  
T. Pass
Keyword(s):  
Latent Period ◽  
Direct Observation ◽  
Germ Tube ◽  
Carbon Starvation ◽  
Glucose Medium ◽  
Glucose Depletion ◽  
High Germination ◽  
Germ Tubes ◽  
Starvation Conditions ◽  
Exogenous Source

Direct observation of washed macroconidia of F. roseum 'Sambucinum' infested in rewetted soil and incubated at 6 °C indicated that germination increased to 79% at 4 days and increased slowly thereafter. Lysis of germ tubes was inhibited and most germ tubes were not lysed even after 48 days incubation. Small two- or three-celled macroconidia were commonly produced on germ tubes. In contrast, peak germination (39%) occurred at 2 days in rewetted soil incubated at 25 °C with germ tube lysis occurring rapidly between 4 and 8 days. Only sparse sporulation was observed. After 9 months, survival of F. roseum 'Sambucinum' was much greater in soil incubated at 6 °C than at 25 °C.Macroconidia required an exogenous source of carbon for high germination and formed one- or two-celled chlamydosporic macroconidia in media lacking exogenous carbon. After 9 months incubation under carbon starvation conditions at 25 °C chlamydosporic macroconidia had a longer latent period and a much slower rate of germination than macroconidia. Germinated macroconidia formed two- or three-celled macroconidia within 24 h when transferred to media lacking exogenous carbon. Four-celled macroconidia were produced by F. roseum 'Sambucinum' in a dilute glucose medium before exhaustion of the glucose while F. solani 'Coeruleum' formed chlamydospores in this medium after glucose depletion. Behavior of F. roseum 'Sambucinum' under carbon starvation conditions is similar to behavior in rewetted soil in the mode of sporulation and in the formation of chlamydosporic macroconidia, but differs by a lack of appreciable germination and by a greatly reduced lysis of fungal structures.

Exogenous carbon and nitrogen requirements for chlamydospore germination by Fusarium solani: dependence on spore density

1970 ◽  
Vol 16 (12) ◽  
pp. 1366-1368 ◽  
Author(s):  
G. J. Griffin
Keyword(s):  
Salt Solution ◽  
Inorganic Salt ◽  
Spore Density ◽  
Solution Ph ◽  
Carbon And Nitrogen ◽  
High Germination ◽  
Germ Tubes ◽  
Chlamydospore Germination ◽  
Exogenous Nitrogen ◽  
Exogenous Source

Chlamydospores were formed on germ tubes of macroconidia of F. solani after germination at 3 × 105 conidia/ml in an inorganic salt solution (pH 5.7) containing glucose (40 μg C/ml) plus NH4Cl (2.6 μg N/ml), and at 3 × 103 conidia/ml in salt solution containing no glucose or NH4Cl. After 5 days, chlamydospores formed in the low conidial density system required an exogenous source of carbon for high germination, whereas chlamydospores formed in the high conidial density system required both exogenous carbon and nitrogen for high germination. Chlamydospores formed in the high conidial density system did not require exogenous nitrogen for high germination when the spore density (chlamydospores plus some ungerminated conidia) was reduced from 3 × 105 to 3 × 104 spores/ml; high germination was observed at 3 × 103 spores/ml in the absence of both exogenous carbon and nitrogen.

Ethanol and carbon-source starvation enhance the accumulation of HSP80 in Neurospora crassa

1988 ◽  
Vol 34 (2) ◽  
pp. 162-168 ◽  
Author(s):  
H. S. Roychowdhury ◽  
M. Kapoor
Keyword(s):  
Heat Shock ◽  
Neurospora Crassa ◽  
Carbon Catabolite Repression ◽  
Normal Growth ◽  
Carbon Starvation ◽  
High Molecular Mass ◽  
Sucrose Starvation ◽  
Shock Response ◽  
Shock Proteins ◽  
Starvation Conditions

In Neurospora crassa, heat shock results in the induction of 9 to 11 heat shock proteins (HSP), of which HSP80 is the most abundant and the first to be synthesized. The induction of HSP80 was investigated during normal growth (2% sucrose) and under sucrose starvation. Transfer of mycelium to a medium supplemented with ethanol stimulated the synthesis of HSP80, even at the normal growth temperature of 28 °C. It was also synthesized under carbon starvation conditions, where the medium was supplemented with 0.02% sucrose, 0.3% acetate, 0.2% lactate, or ethanol. A 30–35 kilodalton polypeptide was induced by heat shock in carbon-sufficient media, but in 0.02% sucrose and 0.3% acetate containing media it was synthesized at normal temperatures. While the overall heat shock response remained unaltered in these cultures, the abundance of HSP90 and HSP70, relative to HSP80, was greater. HSP80 appears to be controlled by carbon-catabolite repression as well as heat shock. Another high molecular mass protein (tentatively designated alc'80') was observed to be induced by heat shock, provided carbon starvation conditions prevailed concurrently.

Anastomosis of germ tubes and migration of nuclei in germ tube networks of the soybean rust pathogen, Phakopsora pachyrhizi

2011 ◽  
Vol 132 (2) ◽  
pp. 163-167 ◽  
Author(s):  
R. Vittal ◽  
H. -C. Yang ◽  
G. L. Hartman
Keyword(s):  
Germ Tube ◽  
Soybean Rust ◽  
Phakopsora Pachyrhizi ◽  
Rust Pathogen ◽  
And Migration ◽  
Germ Tubes

Production of actinomycin D with immobilizedStreptomyces parvullus under nitrogen and carbon starvation conditions

1988 ◽  
Vol 10 (5) ◽  
pp. 331-336 ◽  
Author(s):  
Mina Dalili ◽  
Pao C. Chau
Keyword(s):  
Actinomycin D ◽  
Carbon Starvation ◽  
Starvation Conditions

Ascospore germination, growth in culture, and imperfect spore formation in Cookeina sulcipes and Phillipsia crispata

1975 ◽  
Vol 53 (1) ◽  
pp. 56-61 ◽  
Author(s):  
J. W. Paden
Keyword(s):  
Germ Tube ◽  
Outer Wall ◽  
Wall Layer ◽  
Spore Formation ◽  
Spore Surface ◽  
No Formation ◽  
Ascospore Germination ◽  
Germ Tubes

Ascospores of Cookeina sulcipes germinate by one of two modes: (1) by the production of blastoconidia on sympodially proliferating conidiogenous cells which may arise from any point on the spore surface, and (2) by a thick polar germ tube. No ascospores were seen to germinate both ways. The conidiogenous cells are occasionally modified into narrow hyphae. The blastoconidia germinate readily but are evidently very short-lived. Ascospores of Phillipsia crispata germinate by two polar germ tubes; there is no formation of blastoconidia. In both species the inner ascospore wall separated from an outer wall layer during germination. In culture both C. sulcipes and P. crispata form arthroconidia. The arthroconidia are uninucleate; they germinate readily and reproduce the species when transferred to fresh plates.

Carbon dioxide induces endotrophic germ tube formation in Candida albicans

1990 ◽  
Vol 36 (4) ◽  
pp. 249-253 ◽  
Author(s):  
Ruth C. Mock ◽  
Jordan H. Pollack ◽  
Tadayo Hashimoto
Keyword(s):  
Carbon Dioxide ◽  
Candida Albicans ◽  
Sodium Bicarbonate ◽  
Key Words ◽  
Germ Tube ◽  
Tube Formation ◽  
Chemical Inducers ◽  
Tube Emergence ◽  
Ph Range ◽  
Germ Tubes

Candida albicans formed germ tubes when exposed to air containing 5 to 15% carbon dioxide (CO2). The CO2-mediated germ tube formation occurred optimally at 37 °C in a pH range of 5.5 to 6.5. No germ tubes were produced at 25 °C, even when the optimal concentration of CO2 (10%) was present in the environment. The requirement of CO2 for germ tube formation could be partially substituted by sodium bicarbonate but not by N2. Carbon dioxide was required to be present throughout the entire course of germ tube emergence suggesting that its role is not limited to an initial triggering of morphogenic change. We suggest that carbon dioxide may be a common effector responsible for the germ tube promoting activity of certain chemical inducers for C. albicans. Key words: Candida albican germ tubes, CO2-induced germ tube formation, endotrophic germ tube formation.

scholarly journals Regulation of Pathogenic Spore Germination by CgRac1 in the Fungal Plant Pathogen Colletotrichum gloeosporioides

2011 ◽  
Vol 10 (8) ◽  
pp. 1122-1130 ◽  
Author(s):  
Iris Nesher ◽  
Anna Minz ◽  
Leonie Kokkelink ◽  
Paul Tudzynski ◽  
Amir Sharon
Keyword(s):  
Cell Division ◽  
Plant Pathogen ◽  
Germ Tube ◽  
Colletotrichum Gloeosporioides ◽  
Fluorescent Protein ◽  
Nuclear Division ◽  
Simultaneous Formation ◽  
Content Type ◽  
Germ Tubes

ABSTRACT Colletotrichum gloeosporioides is a facultative plant pathogen: it can live as a saprophyte on dead organic matter or as a pathogen on a host plant. Different patterns of conidial germination have been recognized under saprophytic and pathogenic conditions, which also determine later development. Here we describe the role of CgRac1 in regulating pathogenic germination. The hallmark of pathogenic germination is unilateral formation of a single germ tube following the first cell division. However, transgenic strains expressing a constitutively active CgRac1 (CA-CgRac1) displayed simultaneous formation of two germ tubes, with nuclei continuing to divide in both cells after the first cell division. CA-CgRac1 also caused various other abnormalities, including difficulties in establishing and maintaining cell polarity, reduced conidial and hyphal adhesion, and formation of immature appressoria. Consequently, CA-CgRac1 isolates were completely nonpathogenic. Localization studies with cyan fluorescent protein (CFP)-CgRac1 fusion protein showed that the CgRac1 protein is abundant in conidia and in hyphal tips. Although the CFP signal was equally distributed in both cells of a germinating conidium, reactive oxygen species accumulated only in the cell that produced a germ tube, indicating that CgRac1 was active only in the germinating cell. Collectively, our results show that CgRac1 is a major regulator of asymmetric development and that it is involved in the regulation of both morphogenesis and nuclear division. Modification of CgRac1 activity disrupts the morphogenetic program and prevents fungal infection.

Factors influencing ascospore germination in three species of Sporormiella

1977 ◽  
Vol 55 (14) ◽  
pp. 1908-1914 ◽  
Author(s):  
Shirin Asina ◽  
Kanti Jain ◽  
R. F. Cain
Keyword(s):  
Sodium Acetate ◽  
Germ Tube ◽  
Optimal Level ◽  
Physical Factors ◽  
Optimal Temperature ◽  
Factors Influencing ◽  
Ascospore Germination ◽  
Energy Maximum ◽  
Ph Range ◽  
Exogenous Source

Ascospore germination of Sporormiella intermedia, S. isomera, and S. minima requires sodium acetate as an exogenous source of energy. Maximum ascospore germination occurs at a concentration of 5.0 g/ℓ of sodium acetate in the medium. Among the physical factors studied, the pH of the medium was found to be crucial: germination occurred within a very narrow pH range (5.0–7.0) and reached an optimal level at pH 5.5. The ascospores of S. intermedia and S. isomera germinated between 10 and 30 °C while those of S. minima germinated between 10 and 40 °C. The optimal temperature varied for each species (10–20 °C for S. intermedia; 20–25 °C for S. isomera; 30–35 °C for S. minima). At 30 °C and above, a globose vesicle formed in all three species before the formation of the germ tube. Light had no influence on ascospore germination, nor were external supplies of nitrogen or vitamins necessary for spore germination.

Emergence of the aeciospore germ tubes of Cronartium coleosporioides (=Peridermium stalactiforme) as observed by scanning electron microscope

1970 ◽  
Vol 48 (9) ◽  
pp. 1692-1692 ◽  
Author(s):  
Y. Hiratsuka
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Germ Tube ◽  
Germ Tubes ◽  
Scanning Electron

Germ tubes of Cronartium coleosporioides Arth. (= Peridermium stalactiforme Arth. and Kern) emerged between processes through short irregular slits. Germ tube walls were folded when they emerged and expanded after the emergence.

Direct Observation of Textured Lubricated Area in Starvation Conditions

2016 ◽  
Vol 2016 (0) ◽  
pp. S1150403
Author(s):  
Kazuyuki YAGI ◽  
Shintaro YAMAMOTO ◽  
Joichi SUGIMURA
Keyword(s):  
Direct Observation ◽  
Starvation Conditions
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