CULTURAL STUDIES OF SEXUAL REPRODUCTION OF CERATOCYSTIS FAGACEARUM

1967 ◽  
Vol 45 (8) ◽  
pp. 1235-1242 ◽  
Author(s):  
W. R. Bell ◽  
C. L. Fergus
Keyword(s):  
Cultural Studies ◽  
Sexual Reproduction ◽  
Great Reduction ◽  
Agar Medium ◽  
Distilled Water ◽  
Ceratocystis Fagacearum ◽  
Optimum Ph ◽  
Pyrimidine Moiety

The optimum KH2PO4 concentration for perithecium production by Ceratocystis fagacearum in a semi-synthetic agar medium was 7.4 × 10−1 M. A great reduction in the number of perithecia occurred at 0.1 M and none were formed at 0.2 M concentration. The optimum pH was 5.2 and no perithecia formed at pH 7.0. Either exogenous thiamine or its pyrimidine moiety is absolutely essential for perithecium formation. Pyridoxine, inositol and biotin were not required for growth or reproduction. Receptivity of 14-day-old cultures remained high for longer periods when stored at 12 °C than at 3 °C or 21 °C. Of the 17 isolates studied, 14 produced sterile perithecia before conidia were applied experimentally. Attempts to fertilize these were unsuccessful. Perithecia which did not extrude ascospores formed on colonies following application of conidia. In such perithecia, opened ostiolar hyphae did not necessarily indicate sterility. Neither abrasion of colonies, nor brushing with sterile distilled water or with a filtrate of sonic-disrupted condia, increased sterile perithecium production. However, brushing the colonies with an extract of germinated conidia did increase their formation.

scholarly journals The Effect of pH Stress on the Survival of Rhizobium Trifolii and Sinorhizobium Meliloti in Vitro

2013 ◽  
Vol 70 (2) ◽  
pp. 449-450
Author(s):  
Monica NISTE ◽  
Roxana VIDICAN ◽  
Ioan ROTAR ◽  
Rodica POP
Keyword(s):  
Sinorhizobium Meliloti ◽  
Agar Medium ◽  
Rhizobium Trifolii ◽  
Ph Values ◽  
Optimum Ph ◽  
Yeast Extract Mannitol ◽  
Rhizobial Species ◽  
The Impact ◽  
Different Soils

Nitrogen-fixing symbiotic bacteria known as rhizobia can exist in different soils and adapt to different environmental conditions. The aim of this study was to determine the impact of pH on the growth of Rhizobium trifolii and Sinorhizobium meliloti. Rhizobial species were isolated using yeast extract mannitol agar medium) in which the pH values were adjusted to 5.0, 6.0, 8.0 and 9.0 by adding HCl and NaOH. The optimum pH for rhizobia is neutral or slightly alkaline (pH 8) and they are more sensitive to acidity. Sinorhizobium meliloti developed better in an acid medium compared to Rhizobium trifolii.

scholarly journals Factors Which Influence the Acquisition of Flagella by the Amoeba, Naegleria Gruberi

1956 ◽  
Vol 33 (3) ◽  
pp. 583-603
Author(s):  
E. N. WILLMER
Keyword(s):  
Sodium Bicarbonate ◽  
Sodium Phosphate ◽  
Sodium Lactate ◽  
Lithium Salts ◽  
Distilled Water ◽  
Free Swimming ◽  
Low Concentrations ◽  
Amoeboid Form ◽  
Optimum Ph ◽  
Naegleria Gruberi

1. When placed in distilled water Naegleria gruberi changes from an amoeboid organism, with little evidence of polarity, to a highly polarized free-swimming flagellate. The details of this metamorphosis are described. The change is reversible. 2. Alteration of osmotic pressure is not in itself the direct cause of the metamorphosis, though the loss of certain ions is clearly important. 3. The metamorphosis is favoured by the presence of low concentrations (less than M/80) of sodium bicarbonate, sodium lactate and sodium phosphate. 4. The flagellate form probably occurs most frequently in conditions of neutrality; but, in the presence of phosphate, acid conditions tend to be more favourable to the flagellate form, while in the presence of bicarbonate the optimum pH is nearer pH 8.0. 5. The metamorphosis to the flagellate form is suppressed by a variety of agents including lithium salts, magnesium chloride and the sulphate ion under some conditions. These all act at concentrations which leave the amoeboid form in full activity. In some cases their action is decreased by the presence of bicarbonate in the medium.

scholarly journals Tumebacillus luteolus sp. nov., isolated from soil

2015 ◽  
Vol 65 (Pt_11) ◽  
pp. 4107-4112 ◽  
Author(s):  
Jihee Her ◽  
Sathiyaraj Srinivasan ◽  
Sang-Seob Lee
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
Gene Sequence ◽  
Agar Medium ◽  
Sequence Similarity ◽  
Diaminopimelic Acid ◽  
Rrna Gene ◽  
16S Rrna Gene Sequences ◽  
Optimum Ph ◽  
The 16S Rrna Gene

Two strains of Gram-stain-positive, aerobic, spore-forming and rod-shaped bacteria, designated U13T and U14, were isolated from soil of the Ukraine. Comparative analysis of the 16S rRNA gene sequences indicated that these strains belong to the genus Tumebacillus, with the highest 16S rRNA gene sequence similarity with Tumebacillus ginsengisoli Gsoil 1105T (95.48 % and 95.49 %, respectively). Strains U13T and U14 had iso-C15 : 0 and summed features 1 and 4 as the main fatty acids, and were able to grow at pH ranging from pH 5.0 to 9.0 (optimum pH 6.0–7.0), temperatures ranging from 25 to 42 °C (optimum 28–37 °C) and with 0–1 % (w/v) NaCl (optimum 0 %, w/v) on R2A agar medium. Chemotaxonomic data revealed that the cell-wall peptidoglycan type of the two strains was type A1γ (meso-diaminopimelic acid). On the basis of the evidence from this study, strains U13T and U14 represent a novel species of the genus Tumebacillus, for which the name Tumebacillus luteolus sp. nov. is proposed. The type strain is U13T ( = KEMB 7305-100T = JCM 19866T) and a second strain is U14 ( = KEMB 7305-101 = JCM 19867).

Effect of sodium chloride and seawater in Sabouraud dextrose agar medium on some human-pathogenic fungi

1979 ◽  
Vol 57 (21) ◽  
pp. 2418-2421 ◽  
Author(s):  
Comfort A. Ekundayo
Keyword(s):  
Sodium Chloride ◽  
Agar Medium ◽  
Basal Medium ◽  
Pathogenic Fungi ◽  
Geotrichum Candidum ◽  
Distilled Water ◽  
Sabouraud Dextrose Agar ◽  
Colony Diameter ◽  
Sterile Seawater ◽  
Fungal Isolates

Nine human-pathogenic fungal isolates from Nigeria were cultured on Sabouraud dextrose agar prepared with seawater and solutions containing different concentrations of sodium chloride. Growth was determined by measuring colony diameter after incubation for a maximum of 15 days at 30 °C. The fungi grew and sporulated on seawater, Sabouraud dextrose agar, and Sabouraud dextrose agar containing up to 3.4% NaCl. Growth, however, decreased with increasing concentrations of sodium chloride in the basal medium. Little or no growth occurred in media containing 6.4% NaCl.Aspergillus fumigatus Link, Candida albicans (Robin) Berkh, and Geotrichum candidum Link remained viable for up to 8 weeks in distilled water, 0.85 and 1.7% NaCl solutions, 5 weeks in 3.4% NaCl and sterile seawater, and 4 weeks in 6.8% NaCl.

scholarly journals Fragmentation in the Genus Autolytus and in other Syllids

1927 ◽  
Vol 14 (4) ◽  
pp. 869-876 ◽  
Author(s):  
E. J. Allen
Keyword(s):  
Sexual Reproduction ◽  
Sea Water ◽  
The Body ◽  
Distilled Water ◽  
Ordinary Mode ◽  
Low Salinity ◽  
Anterior Segments

In a former paper (Allen, Phil. Trans. Roy. Soc. B., Vol. 211, p. 131, 1921) it was shown that the Syllid Procerastea Halleziana Malaquin, addition to the ordinary mode of sexual reproduction which occurs in this group, reproduced asexually by a process of fragmentation, followed by the regeneration by each fragment of a new head and series of anterior segments and of a new pygidium and posterior segments. The fragments usually consisted of sections of two, three, or four segments each, in the region of the body behind the seventh setigerous segment. It was further shown that this breaking up of Procerastea, which could be produced artificially at any time by treating the worms with sea-water of low salinity, made by adding distilled water to natural sea-water, took place according to a definite law. The first section consisted normally of the head and setigerous segments 1 to 7, then followed three sections of two segments each (Segments 8 and 9; 10 and 11; 12 and 13), then three sections of three segments (14–16; 17–19; 20–22), followed by four or five sections of four segments each, and then a number of sections of three segments.

scholarly journals Natronorubrum aibiense sp. nov., an extremely halophilic archaeon isolated from Aibi salt lake in Xin-Jiang, China, and emended description of the genus Natronorubrum

2006 ◽  
Vol 56 (7) ◽  
pp. 1515-1517 ◽  
Author(s):  
Heng-Lin Cui ◽  
Dilbr Tohty ◽  
Jie Feng ◽  
Pei-Jin Zhou ◽  
Shuang-Jiang Liu
Keyword(s):  
Gene Sequence ◽  
Agar Medium ◽  
Novel Species ◽  
Salt Lake ◽  
Rrna Gene ◽  
Halophilic Archaeon ◽  
Optimum Ph ◽  
Emended Description ◽  
Extremely Halophilic Archaeon ◽  
Sequence Similarities

An extremely halophilic archaeon (strain 7-3T) was isolated from Aibi salt lake in Xin-Jiang, China. It formed small (<1.0 mm), red, elevated colonies on salt-milk agar medium. Strain 7-3T was able to grow at pH 6.5–9.5 (optimum pH 8.0) and at 20–50 °C (optimum 45 °C). Analysis of its 16S rRNA gene sequence indicated that strain 7-3T was phylogenetically related to members of the genus Natronorubrum, with sequence similarities of 97.0 % to Natronorubrum bangense A33T and 95.2 % to Natronorubrum tibetense GA33T. The G+C content of its DNA was 61.2 mol% (T m). Levels of DNA–DNA relatedness to Nrr. bangense and Nrr. tibetense were 45 and 37 %, respectively. It is concluded that strain 7-3T (=CGMCC 1.4299T=JCM 13488T) should be classified as the type strain of a novel species of the genus Natronorubrum, for which the name Natronorubrum aibiense sp. nov. is proposed. Based on the properties of Nrr. aibiense given here and of those of Nrr. bangense and Nrr. tibetense described previously, an emended description of the genus Natronorubrum is presented.

scholarly journals The Oxidizing Enzymes of Sugarcane: Tyrosinase (Polyphenol oxidase)

1969 ◽  
Vol 50 (2) ◽  
pp. 113-130
Author(s):  
Alex G. Alexander
Keyword(s):  
Ascorbic Acid ◽  
Polyphenol Oxidase ◽  
Room Temperature ◽  
Distilled Water ◽  
Optimum Temperature ◽  
Meristematic Tissue ◽  
Manganese Zinc ◽  
Mesh Screen ◽  
Freeze Dried ◽  
Optimum Ph

A study was made of the distribution and properties of tyrosinase (polyphenol oxidase) in sugarcane. The enzyme was extracted with phosphate buffer (pH 7) from freeze-dried tissues which had been ground to pass a 60-mesh screen. Tyrosinase was assayed spoctrophotometrically at 390 mµ by measuring the optical density increase of a buffered mixture of catechol and enzyme. Fractionation of cane extracts with ammonium sulfate showed that tyrosinase is precipitated readily from 20- to 70-percent saturation. The richest source of the enzyme was meristematic tissue. Considerable activity was also obtained from leaves — 1 and 0, whereas only traces of the enzyme were present in both 8 to 10 and 1 to 3 nodes and internodes. Tyrosinase preparations were heat-sensitive, losing most of their activity within 2-1: hours of extraction at room temperature (28-29°C.) and laboratory temperature (19-21°C). In contrast, to cane peroxidase, no recuperative capacity was evident after inactivation by boiling. Substrates acted upon by tyrosinase included tyrosine, catechol, DOPA (3,4, dihydroxyphenylalanine), pyrogallol, guaicol, resorcinol, hydroquinone, and paracresol. No reaction was observed with phenol or metacresol. Optimum temperature was about 21°C, and optimum pH was 7.5. Apparent Km was 4.0 X 10-3 mols of catechol per liter. Thiourea and hydroxylamine markedly inhibited the enzyme at concentrations of 1 umol/ml.  Cysteine, ascorbic acid, and cyanide caused virtually complete inhibition at this concentration. Carbon monoxide likewise inhibited. Tyrosinase which was inactivated by KCN was reactivated following prolonged dialysis against distilled water and addition of copper. No other metal tested (molybdenum, manganese, zinc, iron, magnesium) served to reactivate the catalyst. Possible roles and significance of cane tyrosinase are discussed.

scholarly journals Growth effectivity of molds in contact with methylxanthines

2019 ◽  
Vol 282 ◽  
pp. 02058
Author(s):  
Klára Kobetičová ◽  
Václav Kočí ◽  
Michaela Petříková ◽  
Kristýna Šimůnková ◽  
Robert Černý
Keyword(s):  
Building Materials ◽  
Agar Medium ◽  
The Other ◽  
Distilled Water ◽  
Toxic Substances ◽  
Mold Growth ◽  
Chemical Substances ◽  
Test Conditions ◽  
Solid Agar ◽  
Specific Species

Molds on buildings can cause health- and aesthetic problems. Looking for suitable cheap and non-toxic substances to eliminate them is therefore an actual task. In the present study, effect of three selected methylxanthines (1,3,7-trimethylpurine-2,6-dione, 3,7-dihydro-3,7-dimethyl-1H-purine-2,6-dione and 1,3-dimethylxanthine) on growth of non-specific species of molds occurring on building materials were tested on agar medium under laboratory conditions. The chemical substances were dissolved in distilled water and applied into agar. Solid agar has been exposed to air molds for 24 hours. Agar plates were then covered with lids and placed for 5 days in a laboratory thermostat at stable test conditions (dark place, 25 °C). After that, the mycelium was observed. The results showed that 3,7-dihydro-3,7-dimethyl-1H-purine-2,6-dione and 1,3- dimethylxanthine were not effective against the molds growth. On the other hand, 1,3,7-trimethylpurine-2,6-dione was able to eliminate mold growth on agar medium at a concentration of 1 g∙l-1 or higher.

Maintaining cultures of ectomycorrhizal and plant pathogenic fungi in sterile water cold storage

1976 ◽  
Vol 22 (3) ◽  
pp. 338-341 ◽  
Author(s):  
Donald H. Marx ◽  
William J. Daniel
Keyword(s):  
Agar Medium ◽  
Water Storage ◽  
Pathogenic Fungi ◽  
Fungal Species ◽  
Plant Pathogenic Fungi ◽  
Distilled Water ◽  
Sterile Water ◽  
Pine Seedlings ◽  
Symbiotic Fungi ◽  
Petri Dishes

Mycelial cultures of 64 isolates of 14 species of ectomycorrhizal fungi and 27 isolates of 15 species of plant pathogenic fungi were grown on agar medium in Petri dishes. Mycelial discs, 8 mm in diameter, were removed from the cultures and stored in sterile distilled water in test tubes at 5 °C. Sixty-four, 61, and 41 isolates of the symbiotic fungi were viable after 1, 2, and 3 years storage respectively. Only 19, 10, and 8 isolates of the pathogenic fungi were viable after 1, 2, and 3 years storage, respectively. Time in pure culture before water storage did not affect viability of any fungal species following water storage. After 3 years storage, four fungi (three symbionts and one pathogen) were tested and found to have retained their original growth rates and root-infecting abilities on pine seedlings. The same four isolates, however, maintained on agar slants at 5 °C and subcultured every 4 to 6 months, grew slower and did not infect as many feeder roots of pine as the water-stored isolates.

scholarly journals In Vitro Propagation of Isoëtes sabatina (Isoetaceae): A Key Conservation Challenge for a Critically Endangered Quillwort

Plants ◽  
2020 ◽  
Vol 9 (7) ◽  
pp. 887
Author(s):  
Sara Magrini ◽  
Mattia M. Azzella ◽  
Rossano Bolpagni ◽  
Laura Zucconi
Keyword(s):  
Habitat Quality ◽  
In Vitro Propagation ◽  
Agar Medium ◽  
Development Stage ◽  
Critically Endangered ◽  
Distilled Water ◽  
Restricted Range ◽  
Optimized Protocol

Isoëtes sabatina is an aquatic quillwort endemic to Italy. It is one of the rarest quillworts in Europe, and is critically endangered due to restricted range and to the continuous decline of both population and habitat quality. This study aims to develop an optimized protocol to reproduce and grow I. sabatina sporelings. Mature and immature megaspores were mixed with mature microspores to evaluate the influence of the developmental stage on germination and sporeling development. Two substrates, distilled water and water-agar medium, were tested for germination and sporeling emergence, and three substrates, sand, lake sediment and water-agar, were tested for transplants. A high percentage of megaspore germination (a total of 79.1%) was obtained in both substrates, higher for mature than immature spores. A total of 351 sporelings were produced in distilled water and water-agar cultures, with similar percentages (64.5% and 69.6%, respectively). The development stage of the megaspores affected both germination and sporeling development. Sporeling emergence showed significantly higher percentages in mature megaspores than immature ones (69.6% vs. 11.6%, respectively), with 85% of germinated spores developing sporelings. Only transplants over water-agar medium were successful. This protocol could be useful for the propagation of sporelings as the key step towards the planning of in situ actions to save this Mediterranean quillwort from extinction.

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