Multifactor experiment on a nutritive medium

This study had as principal objective identification of osmotic-tolerant potato genotypes by using "in vitro" tissue culture and sorbitol as a stimulating agent, to induce water stress, which was added to the culture nutritive medium in different concentration (0,50, 110, 220, 330 and 440 mM). The starting point was represented by plantlets culture collection, belonging to eleven potato genotypes: Barcelona, Nectar, Alison, Jelly, Malice, Nazca, Toronto, Farida, Fabulla, Colomba and Spunta. Plantlets were multiplied between two internodes to obtain microcuttings (in sterile condition), which were inoculated on medium. Sorbitol-induced osmotic stress caused a significant reduction in the ascorbic acid, while the concentration of proline, H2O2 and solutes leakage increased compared with the control. Increased the proline content prevented lipid peroxidation, which played a pivotal role in the maintenance of membrane integrity under osmotic stress conditions. The extent of the cytoplasmic membrane damage depends on osmotic stress severity and the genotypic variation in the maintenance of membranes stability was highly associated with the ability of producing more amounts of osmoprotectants (proline) and the non-enzymic antioxidant ascorbic acid in response to osmotic stress level. The results showed that the genotypes Jelly, Nectar, Allison, Toronto, and Colomba are classified as highly osmotic stress tolerant genotypes, while the genotypes Nazca and Farida are classified as osmotic stress susceptible ones.

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Mineral fertilizers as a governing factor of the regulation of the number of fungi in soil

Zbornik Matice srpske za prirodne nauke ◽

10.2298/zmspn0916201p ◽

2009 ◽

pp. 201-207 ◽

Cited By ~ 2

Author(s):

Marijana Pesakovic ◽

Dragutin Djukic ◽

Leka Mandic ◽

Milan Rakicevic ◽

Rade Miletic

Keyword(s):

Soil Fungi ◽

Mineral Fertilizer ◽

Mineral Fertilizers ◽

Nitrogen Rate ◽

Nutritive Medium ◽

Governing Factor ◽

Npk Fertilizer ◽

Set Up ◽

The One ◽

Fertilizer Rates

Over 2003-2005 period, a study was performed on the effect of different rates of NPK fertilizer of formulation 8:16:24 + 3% MgO (N1 - 400 kg ha-1; N2 - 600 kg ha-1; N3 - 800 kg ha-1; N4 - 1000 kg ha-1) on development of the soil fungi. The trial was set up in the experimental plum orchard established by Fruit Research Institute Cacak, and the laboratory of Department of Microbiology, Faculty of Agronomy Cacak. Unfertilized soil was used as the control soil. Each of the stated variants was carried out in three replications. The size of the basic plot was 68 m2. The effect of the studied mineral fertilizer rates was determined three times over the growing season, the number of fungi being checked by the indirect rarefaction method on Chapek nutritive medium. The results of the study inferred that the application of mineral fertilizers brought about the decrease in the number of fungi. Of all studied variants, the one with the highest nitrogen rate (variant N4) exhibited the strongest effect. The influence of the fertilizer was highest at the third sampling. Furthermore, the effect was highest in season 2003.

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Mycopopulation of spices

Acta periodica technologica ◽

10.2298/apt0839001d ◽

2008 ◽

pp. 1-9 ◽

Cited By ~ 5

Author(s):

Gordana Dimic ◽

Suncica Kocic-Tanackov ◽

Aleksandra Tepic ◽

Biserka Vujicic ◽

Zdravko Sumic

Keyword(s):

Ochratoxin A ◽

Nutritive Medium

The presence of fungi in cinnamon, marjoram, caraway and clove was investigated. Total fungal counts determined on SMA nutritive medium ranged from 8.0 (clove) to 3.3 ? 104 per g (caraway) and from 6.0 to 5.2 ? 104 per g on MY50G medium for the same spices. The most frequent contaminants of spice samples were the genera: Eurotium (90%), Aspergillus (80%), Penicillium (75%), Cladosporium (45%), Rhizopus, Scopulariopsis and Syncephalastrum (25%). Producers of sterigmatocystin (80%) were dominant. Producers of aflatoxin (60%) and ochratoxin A (30%) were isolated from the samples.

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Kinetics of endosomal pH evolution in Dictyostelium discoideum amoebae. Study by fluorescence spectroscopy

Journal of Cell Science ◽

10.1242/jcs.105.3.861 ◽

1993 ◽

Vol 105 (3) ◽

pp. 861-866 ◽

Cited By ~ 11

Author(s):

L. Aubry ◽

G. Klein ◽

J.L. Martiel ◽

M. Satre

Keyword(s):

Dictyostelium Discoideum ◽

Fluid Phase ◽

Lag Phase ◽

Nutritive Medium ◽

Chase Period ◽

Endosomal Acidification ◽

Fluid Phase Endocytosis ◽

Endosomal Ph ◽

Efflux Kinetics ◽

Secondary Lysosomes

The evolution of endo-lysosomal pH in Dictyostelium discoideum amoebae was examined during fluid-phase endocytosis. Pulse-chase experiments were conducted in nutritive medium or in non-nutritive medium using fluorescein labelled dextran (FITC-dextran) as fluid-phase marker and pH probe. In both conditions, efflux kinetics were characterized by an extended lag phase lasting for 45–60 min and corresponding to intracellular transit of FITC-dextran cohort. During the chase period, endosomal pH decreased during approximately 20 min from extracellular pH down to pH 4.6-5.0, then, it increased within the next 20–40 min to reach pH 6.0-6.2. It was only at this stage that FITC-dextran was released back into the medium with pseudo first-order kinetics. A vacuolar H(+)-ATPase is involved in endosomal acidification as the acidification process was markedly reduced in mutant strain HGR8, partially defective in vacuolar H(+)-ATPase and in parent type strain AX2 by bafilomycin A1, a selective inhibitor of this enzyme. Our data suggest that endocytic cargo is channeled from endosomes to secondary lysosomes that are actively linked to the plasma membrane via recycling vesicles.

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CULTIVATION OF POLIOMYELITIS VIRUS IN TISSUE CULTURE

Canadian Journal of Medical Sciences ◽

10.1139/cjms52-031 ◽

1952 ◽

Vol 30 (3) ◽

pp. 231-245 ◽

Cited By ~ 1

Author(s):

Joan C. Thicke ◽

Darline Duncan ◽

William Wood ◽

A. E. Franklin ◽

A. J. Rhodes

Keyword(s):

Tissue Culture ◽

Cell Morphology ◽

Synthetic Medium ◽

Embryonic Brain ◽

Human Embryonic Kidney ◽

Virus Growth ◽

Nutritive Medium ◽

Poliomyelitis Virus ◽

Cytopathogenic Effect ◽

And Control

This paper presents observations on the growth of Lansing poliomyelitis virus in fluid cultures of various human embryonic and adult tissues. The evidence suggests that viral multiplication has occurred in cultures of monkey testis, human embryonic kidney, and mixtures of brain and cord. Satisfactory virus growth has been obtained particularly in cultures containing human embryonic brain and cord. Virus is present in tissue culture fluids in which the original inoculum has been diluted 10−33.3 by subcultivation. Preliminary observations suggest that a synthetic medium (Mixture 199) devised by Morgan, Morton, and Parker is superior to Hanks–Simms solution as a nutritive medium in such cultures. The cytopathogenic effect of the virus, as revealed by pH determinations and cell morphology, has been noted, although a characteristic pH differential between virus infected and control flasks was not commonly observed. Attempts to grow the virus on a larger scale in Kolle flasks are described.

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