Effect of explant's size and phytohormonal composition of nutritive medium on post-vitification recovery of garlic meristems

2015 ◽  
Vol 25 (1) ◽  
pp. 13-23
Author(s):  
Mariya V. Shevchenko ◽  
◽  
Aleksandr N. Sukach ◽  
Keyword(s):  
Nutritive Medium

IMPACT OF SORBITOL- INDUCED OSMOTIC STRESS ON SOME BIOCHEMICAL TRAITS OF POTATO IN VITRO

2020 ◽  
Vol 51 (4) ◽  
pp. 1038-1047
Author(s):  
Mawia & et al.
Keyword(s):  
Ascorbic Acid ◽  
Osmotic Stress ◽  
Cytoplasmic Membrane ◽  
Genotypic Variation ◽  
Membrane Damage ◽  
Membrane Integrity ◽  
Culture Collection ◽  
Nutritive Medium ◽  
Starting Point

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.

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

2009 ◽  
pp. 201-207 ◽  
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.

scholarly journals Mycopopulation of spices

2008 ◽  
pp. 1-9 ◽  
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.

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

1993 ◽  
Vol 105 (3) ◽  
pp. 861-866 ◽  
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.

Multifactor experiment on a nutritive medium

2021 ◽  
pp. 87-92
Author(s):  
E. J. Snell ◽  
H. R. Simpson
Keyword(s):  
Nutritive Medium ◽  
Multifactor Experiment

CULTIVATION OF POLIOMYELITIS VIRUS IN TISSUE CULTURE

1952 ◽  
Vol 30 (3) ◽  
pp. 231-245 ◽  
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.

Fruit Flies & the Gut Microbiome: Redesign-Your-Bacteria Lab Exercise

2019 ◽  
Vol 81 (1) ◽  
pp. 47-51 ◽  
Author(s):  
Elizabeth Skendzic ◽  
Cynthia Keler
Keyword(s):  
Experimental Design ◽  
Gut Microbiome ◽  
Food Additives ◽  
Model System ◽  
Fruit Flies ◽  
Significant Gain ◽  
Gram Stain ◽  
Nutritive Medium ◽  
The Impact ◽  
Mrs Medium

This lab introduces students to experimental design in an inquiry lab exercise that investigates the gut microbiome, basic microbiology techniques, and the broader topic of bacteriology. Fruit flies are used as a model system to study the impact that foods, food additives, and/or antibiotics have on the gut microbiome. One of the major bacteria in the guts of fruit flies is Lactobacillus, which is easy to grow in the lab. This exercise is done in three consecutive lab sessions. During Lab 1, students prepare a standard nutritive medium that has been mixed with a substance of their choice, add the fruit flies to the medium, and practice serial dilution with a simulation. During Lab 2, students plate mashed fruit flies on MRS medium to look at the change in Lactobacillus levels. During Lab 3, students count and determine the change in the number of Lactobacillus in their tested substance, Gram stain selected colonies, and discuss their results as a class. SALG surveys indicated a significant gain in their understanding of the microbiology concepts introduced in this lab.

scholarly journals Chemical Composition of Celandine (Chelidonium majus L.) Extract and its Effects on Botrytis tulipae (Lib.) Lind Fungus and the Tulip

2013 ◽  
Vol 41 (2) ◽  
pp. 414 ◽  
Author(s):  
Marcel PARVU ◽  
Laurian VLASE ◽  
Laszlo FODORPATAKI ◽  
Ovidiu PARVU ◽  
Oana ROSCA-CASIAN ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Gas Exchange ◽  
Plant Extract ◽  
Transpiration Rate ◽  
Photosynthetic Apparatus ◽  
Chelidonium Majus ◽  
Gas Exchange Parameters ◽  
Nutritive Medium ◽  
Exchange Parameters

In this study, the content of chelidonine and berberine alkaloids, and sterols and phenols in the Chelidonium majus plant extract were analyzed. Subsequently, the effects of the extract on the germination and growth of Botrytis tulipae fungus on nutritive medium were compared to the effects of fluconazole. The plant extract was used at the minimum inhibitory concentration on B. tulipae developed in tulip leaves and the in vivo effects were investigated. The influence of different concentrations of C. majus extract on the physiological processes of the tulip (gas exchange parameters, photosynthetic light use efficiency, and induced chlorophyll fluorescence) were also tested to assess the applicability of the extract for the protection of ornamental plants against fungal infection. Our results demonstrated that 2% celandine extract does not significantly change the gas exchange parameters (transpiration rate, carbon dioxide uptake, and stomatal conductivity) of leaves exposed for 2 h, and does not interfere with the photochemical processes in the leaves. However, in higher concentrations, it increases the transpiration rate and net carbon dioxide influx. At concentrations of 15% and 20%, the extract lowers the potential quantum yield efficiency of photosystem II and the vitality index of the photosynthetic apparatus. Therefore we recommend the use of lower concentrations (≤6%) of celandine extract for the biological protection of tulips against gray mold.

Paper 7: Properties of Synovial Fluid

1966 ◽  
Vol 181 (10) ◽  
pp. 25-29 ◽  
Author(s):  
D. V. Davies
Keyword(s):  
Hyaluronic Acid ◽  
Synovial Fluid ◽  
Normal Animal ◽  
Chemical Components ◽  
Weissenberg Rheogoniometer ◽  
Nutritive Medium ◽  
Shear Rates ◽  
Joint Lubrication ◽  
Normal Human ◽  
Human Joints

Synovial fluid functions both as a lubricant and as a nutritive medium in joints. Its chemical composition suggests that it is a dialysate of blood plasma with the addition of the mucosubstance, hyaluronic acid. In addition the fluid contains a small cellular component. The quantities of some of the chemical components are apparently anomalous and need explanation. The hyaluronic acid, probably combined with a small amount of protein, is believed to be secreted by the cells lining the joint cavity, the synovial cells. The volume and naked eye appearance of the fluid vary from joint to joint in the same species and in the same joint from species to species. The volume of fluid that can be aspirated from normal human joints is too small for most chemical and physical investigations and recourse must be made to fluids from the larger domestic animals and to pathological human fluids. The most characteristic property of the fluid is its viscosity. This has been investigated using the Weissenberg rheogoniometer. This allows of a study of the viscosity and elasticity of the fluids at different shear rates. Results on fluid from both normal animal joints and pathological human joints will be presented. Their relevance in joint lubrication will be discussed.

The Behaviour of Larvae of Culicoides circumscriptus Kieff. (Dipt., Ceratopogonidae) towards Light Stimuli as influenced by Feeding, with Observations on the Feeding Habits

1958 ◽  
Vol 49 (4) ◽  
pp. 785-802 ◽  
Author(s):  
P. Becker
Keyword(s):  
Feeding Habits ◽  
Fourth Instar ◽  
The Other ◽  
Larval Diet ◽  
Surface Material ◽  
Nutritive Medium ◽  
Nutritional Needs ◽  
Light Stimuli ◽  
Series Of Experiments ◽  
Size Of Particles

The larvae of Culicoides circumscriptus Kieff. are mostly negatively phototactic when extracted from mud and placed in water. Experiments show, however, that if kept without food over a period of time a large proportion becomes positively phototactic. The provision of food causes them to revert to a photonegative taxis which may be permanent as long as suitable food is given, or temporary if the food does not satisfy their nutritional requirements. On the other hand, the provision of a completely non-nutritive medium does not bring about such a reversion. The significance of this behaviour is discussed in the light of the habits of the larvae in the field.Most of the experiments were carried out with batches of fourth-instar larvae, but in a few, third-instar larvae and fourth-instar larvae near to pupation were used. From the results it is suggested that the processes of ecdysis and pupation may bring about a reversal from photonegative to photopositive taxis independent of the need for food.The significance of the behaviour of the larvae towards light stimuli is discussed in relation to their habits in the field. It is assumed that its function is to maintain the larvae on the surface of the mud while feeding and to drive them below when they have fed, and that some other type of tropism must initially drive them to the surface or keep them below according to their nutritional needs.It is shown that the behaviour towards light stimuli of the larvae of C. maritimus Kieff. differs somewhat from that of C. circumscriptus and reasons are suggested for this.A second series of experiments designed to throw some light on the food requirements of the larvae is described. In a discussion on the results of these it is shown that the larvae feed on material both on the surface of the mud and below the surface, and it is suggested that larvae which have fed on sub-surface food become positively phototactic when they require food from the surface and, having fed there, revert to photonegative behaviour. If, however, photopositive larvae have not previously had the opportunity to feed on sub-surface material they continue to act as completely starved larvae and remain photopositive in spite of their having fed on surface material.The detailed constituents of the larval diet have not been worked out. The larvae appear to be detritus feeders, feeding mainly on vegetable matter and bacteria obtained on or below the surface of the mud, though green algae are not an important part of their diet. They are carnivorous on occasion but are normally not so when other food is readily available. They are selective in their choice of food and at least three factors, sapidity, texture and the size of particles, appear to influence this selection.

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