In vitro germination of Entomophthora egressa resting spores

1976 ◽  
Vol 54 (10) ◽  
pp. 1131-1134 ◽  
Author(s):  
Richard A. Nolan ◽  
Gary B. Dunphy ◽  
Donald M. MacLeod
Keyword(s):  
Spore Germination ◽  
Germ Tube ◽  
In Vitro Germination ◽  
Effect Of Ph ◽  
High Ph ◽  
Ph Values ◽  
Resting Spore ◽  
Resting Spores ◽  
Hyphal Bodies

The resting spores of Entomophthora egressa MacLeod and Tyrrell germinated to produce a single germ tube, which in turn, produced a solitary, terminal germ conidium. The level of resting spore germination obtained in shaken, liquid, steam-sterilized media after 12 h of incubation at pH 7.5 was 93%. The effect of pH on resting spore germination in filter-sterilized media was investigated; in the range pH 4.5 to 9.5, pH 8.5 and 9.5 were optimal (100% germination after 96 h). No germination occurred at pH 4.5 to 6.5 before 96 h. At values greater than pH 6.5, the proportion of resting spores which germinated to form a single germ tube with a solitary germ conidium decreased, and the resting spores increasingly germinated by forming one to five hyphae. At high pH values (pH 7.5 to 9.5) septa occurred in the hyphae after 120 h of incubation. This latter phenomenon may have been correlated with the occurrence of hyphal bodies in shaken media at high pH (pH 8.5). The germination of resting spores to form hyphae at high pH levels may indicate the presence of a mechanism for infection via the gut.

In vitro germination of Entomophthora aphidis resting spores

1975 ◽  
Vol 53 (12) ◽  
pp. 1188-1191 ◽  
Author(s):  
David Tyrrell ◽  
Donald M. MacLeod
Keyword(s):  
Germ Tube ◽  
Terminal Cell ◽  
In Vitro Germination ◽  
Germination Process ◽  
Resting Spores ◽  
Nutrient Reserves

On germination, resting spores of Entomophthora aphidis produce a septate sporogenous germ tube, which in turn gives rise to two or occasionally three germ conidia, one conidium being formed by the terminal cell and the others from cells lower down the tube. The resting spores possess sufficient endogenous nutrient reserves to complete the germination process.

Aliphatic acids as spore germination inhibitors of wood-decay fungi in vitro

1985 ◽  
Vol 63 (2) ◽  
pp. 337-339 ◽  
Author(s):  
Elmer L. Schmidt
Keyword(s):  
Spore Germination ◽  
Germ Tube ◽  
White Rot Fungi ◽  
Wood Decay ◽  
White Rot ◽  
Malt Extract ◽  
Decay Fungi ◽  
Aliphatic Acids ◽  
Wood Decay Fungi

Influences of eight saturated aliphatic acids (C5–C10, C12, and C16) on basidiospores of four isolates of wood-decay fungi (Poria tenuis and Trametes hispida, white rot fungi, and two isolates of the brown rot fungus Gloeophyllum trabeum) were observed in vitro. Spore responses after 24 h on malt extract agar containing 10, 102 or 103 ppm of each acid included normal germination, delay of germ tube emergence, vacuolation and degeneration of spore cytoplasm, and prevention of germ tube development without spore destruction. Acids of chain length C5–C10 prevented spore germination and killed spores of all fungi at concentrations of 20–50 ppm in media, whereas other acids tested were less active. Spore germination assay of decay fungi may prove useful as a screening tool to compare potency of wood preservatives.

Effect of light exposure on in vitro germination and germ tube growth of eight species of rust fungi

Mycologia ◽  
2010 ◽  
Vol 102 (5) ◽  
pp. 1134-1140 ◽  
Author(s):  
James W. Buck ◽  
Weibo Dong ◽  
Daren S. Mueller
Keyword(s):  
Germ Tube ◽  
Light Exposure ◽  
Rust Fungi ◽  
Tube Growth ◽  
In Vitro Germination ◽  
Effect Of Light ◽  
Germ Tube Growth

The effect of temperature on in vitro germination and germ tube growth of urediniospores of Tranzschelia discolor

1990 ◽  
Vol 41 (3) ◽  
pp. 479 ◽  
Author(s):  
PJ Ellison ◽  
BR Cullis ◽  
RW Bambach ◽  
PF Kable
Keyword(s):  
Germ Tube ◽  
Three Dimensional ◽  
Tube Growth ◽  
Effect Of Temperature ◽  
In Vitro Germination ◽  
Three Dimensional Models ◽  
C 30 ◽  
Tranzschelia Discolor ◽  
Germ Tube Growth

The effect of temperature on in vitro germination and germ tube growth of urediniospores of Tranzschelia discolor was studied over time under constant temperature conditions. Studies were carried out on 1% water agar in the dark at 3�C, 5�C, 8�C, 10�C, 15�C, 20�C, 25�C, 28�C, 30�C and 32�C. Germination was observed at all temperatures between 5 and 30'C, and occurred rapidly over most of this range. At 2 h, germination exceeded 80% at temperatures between 10 and 28�C, and this level was reached at 3 h at 8�C. Germination at 5 and 30�C was much reduced and at 7 h reached only 44% and 38% respectively. Germ tube growth occurred most vigorously at 15 and 20�C, reaching lengths in excess of 500 8m at 9 h. The optimum range was narrower than that for germination, and growth was reduced or poor at 8�C, 10�C, 25�C and 28�C, which were favourable temperatures for germination. Average germ tube lengths at 9 h at these temperatures were 55, 245, 273 and 62 8m, respectively. Three-dimensional models were derived relating germination and germ tube growth to time and temperature.

scholarly journals Pecan Pollen Stored Over a Decade Retains Viability

HortScience ◽  
2002 ◽  
Vol 37 (1) ◽  
pp. 176-177 ◽  
Author(s):  
Darrell Sparks ◽  
I.E. Yates
Keyword(s):  
Liquid Nitrogen ◽  
Pollen Morphology ◽  
Germ Tube ◽  
Pollen Grains ◽  
Carya Illinoinensis ◽  
In Vitro Germination ◽  
Fresh Pollen

In vitro germination of freshly collected pollen and pollen stored 1, 10, 11, 12, and 13 years in liquid nitrogen was examined for `Desirable' pecan [Carya illinoinensis (Wangenh.) C. Koch]. Viability of pollen stored in liquid nitrogen for 1, 10, 11, 12, and 13 years was not diminished in comparison to that of fresh pollen. Morphology of stored pollen grains and the germ tube was normal. Thus, liquid nitrogen may offer a means of haploid preservation of pecan.

scholarly journals In vitro effect of substrate, temperature and photoperiod on Phakopsora pachyrhizi urediniospore germination and germ tube growth

2015 ◽  
Vol 41 (2) ◽  
pp. 101-106
Author(s):  
Marta Maria Casa Blum ◽  
Erlei Melo Reis ◽  
Francieli Tavares Vieira ◽  
Rita Carlini
Keyword(s):  
Substrate Temperature ◽  
Spore Germination ◽  
Leaf Extract ◽  
Germ Tube ◽  
Tube Growth ◽  
Tube Length ◽  
Germ Tube Length ◽  
Soybean Leaf ◽  
Germ Tube Growth

In vitro experiments were conducted to assess the effects of substrate, temperature and time of exposure to temperature and photoperiod on P. pachyrhizi uredospore germination and germ tube growth. The following substrates were tested: water-agar and soybean leaf extract-agar at different leaf concentrations (0.5, 1.0, 2.0 and 4.0 g of leaves and 15g agar/L water), temperatures (10, 15, 20, 25, 30, and 35oC) and times of exposure (1, 2, 3, 4, 5, 6, 7, and 8 hours) to temperature and 12 different photoperiods. The highest germination and germ tube length was found for the soybean leaf extract agar. Maximum P. pachyrhizi uredospore germination was obtained at 21.8 and 22.3°C, and maximum germ tube growth at 21.4 and 22.1°C. The maximum uredospore germination was found at 6.4 hours exposure, while the maximum germ tube length was obtained at 7.7 h exposure. Regarding photoperiod, the maximum spore germination and the maximum uredospore germ tube length were found in the dark. Neither spore germination nor uredospore germ tube growth was completely inhibited by the exposure to continuous light.

scholarly journals Hydrogen bonds are a primary driving force forde novoprotein folding

2017 ◽  
Vol 73 (12) ◽  
pp. 955-969 ◽  
Author(s):  
Schuyler Lee ◽  
Chao Wang ◽  
Haolin Liu ◽  
Jian Xiong ◽  
Renee Jiji ◽  
...  
Keyword(s):  
Protein Folding ◽  
Hydrogen Bonds ◽  
Driving Force ◽  
De Novo ◽  
High Ph ◽  
Proline Isomerization ◽  
Ph Values ◽  
Protein Secondary Structures

The protein-folding mechanism remains a major puzzle in life science. Purified soluble activation-induced cytidine deaminase (AID) is one of the most difficult proteins to obtain. Starting from inclusion bodies containing a C-terminally truncated version of AID (residues 1–153; AID153), an optimizedin vitrofolding procedure was derived to obtain large amounts of AID153, which led to crystals with good quality and to final structural determination. Interestingly, it was found that the final refolding yield of the protein is proline residue-dependent. The difference in the distribution ofcisandtransconfigurations of proline residues in the protein after complete denaturation is a major determining factor of the final yield. A point mutation of one of four proline residues to an asparagine led to a near-doubling of the yield of refolded protein after complete denaturation. It was concluded that the driving force behind protein folding could not overcome thecis-to-transproline isomerization, orvice versa, during the protein-folding process. Furthermore, it was found that successful refolding of proteins optimally occurs at high pH values, which may mimic protein foldingin vivo. It was found that high pH values could induce the polarization of peptide bonds, which may trigger the formation of protein secondary structures through hydrogen bonds. It is proposed that a hydrophobic environment coupled with negative charges is essential for protein folding. Combined with our earlier discoveries on protein-unfolding mechanisms, it is proposed that hydrogen bonds are a primary driving force forde novoprotein folding.

scholarly journals Leaf Characteristics of Euoalyptus Bicostata Maiden Et Al. Seedlings Affecting the Deposition and Germination of Spores of Phaeoseptoria Eucalypti (Hansf.) Walker

1967 ◽  
Vol 20 (6) ◽  
pp. 1155 ◽  
Author(s):  
WA Heatrer
Keyword(s):  
Negative Correlation ◽  
Spore Germination ◽  
Soluble Fraction ◽  
Water Soluble ◽  
Leaf Angle ◽  
In Vitro Germination ◽  
Water Soluble Fraction ◽  
Unit Leaf ◽  
Water Suspensions

The water�soluble fraction of the ether�soluble moiety of the glaucous coating on the juvenile leaves of seedlings of Eucalyptus bicostata Maiden et al. inhibited the in vitro germination of the conidia of Phaeoseptoria eucalypti (Hansf.) Walker. A negative correlation was obtained between susceptibility of leaves to P. eucalypti leaf spot and the weight per unit leaf area of ether-soluble substances also soluble in water. Glaucousness of seedling leaves and inhibition of spore germination both increased acropetally, glaucousness also increasing when seedlings were raised at lower temperatures. The glaucous coating of leaves was strongly hydrophobic and affected the deposition of conidia from water suspensions as did the leaf angle.

The effect of light and temperature on in vitro germination and germ tube growth of urediniospores of Tranzschelia discolor

1992 ◽  
Vol 43 (3) ◽  
pp. 451 ◽  
Author(s):  
PJ Ellison ◽  
BR Cullis ◽  
PF Kable
Keyword(s):  
Light Intensity ◽  
Germ Tube ◽  
Tube Growth ◽  
Tube Length ◽  
In Vitro Germination ◽  
Germ Tube Length ◽  
Tranzschelia Discolor ◽  
Effect Of Light ◽  
Germ Tube Growth

The effect of light on in vitro germination of urediniospores of Tranzschelia discolor was studied over time at different intensitities (up to 400 8E m-2 s-l) within the temperature range 5�C to 20�C. A model was also developed from the data to predict germination at different combinations of light, temperature and times of leaf wetness. Light retarded the germination process, and its effect increased in direct proportion to intensity. At 20�C, for example, the time taken to exceed 80% germination increased from 2 h in the dark to 9 h at 200 8E m-2 s-l. The model showed that there was an interaction between light and temperature, with the effect of light becoming more pronounced as the temperature declined below 20�C. Germination percentages of the order of 90% were, however, recorded within 24 h at all combinations of light intensity and temperature studied. Light also influenced germ tube growth, causing a reduction in the rate of growth. As in germination, its effect increased with increasing light intensity. At 20�C, the average germ tube length at 9 h was 541 8m in the dark, compared with 227 8m at 200 8E m-2 s-1 and 148 8m at 400 8E m-2 s-l. A similar effect was observed at 5�C, where the average germ tube length at 24 h was 274 8m in the dark compared with 157 8m at 200 8E m-2 s-l. The effects of light on the germination and germ tube growth of urediniospores under field conditions are discussed.

Sign in / Sign up

Export Citation Format

Share Document