scholarly journals Effects of temperature on in vitro response of Trichoderma strains against strawberry pathogen Rhizoctonia solani Kühn.

2017 ◽  
Vol 38 (SI 2 - 6th Conf EFPP 2002) ◽  
pp. 620-622
Author(s):  
M. Porras ◽  
C. Barrau ◽  
B. Santos ◽  
F.T. Arroyo ◽  
C. Blanco ◽  
...  
Keyword(s):  
Rhizoctonia Solani ◽  
Analysis Of Variance ◽  
Radial Growth ◽  
Local Strain ◽  
Effect Of Temperature ◽  
Trichoderma Spp ◽  
Inhibiting Effect ◽  
In Vitro Response ◽  
Effects Of Temperature

Effect of temperature on growth and antagonistic ability of Trichoderma spp. isolated from local strawberry culture and commercial product, against Rhizoctonia solani, strawberry pathogen, was studied in vitro. Trials were carried out twice, at 10, 25 and 30°C. Inhibitor effect was evaluated by radial growth measures of established duals on PDA’s dishes, using Royse and Ries formula, to evaluate the percentage inhibition of radial growth. Design of dishes was a randomized complete block, considering 10 replicates. Data were analyzed statistically by two-way analysis of variance. The objective has been to determine the most competitive Trichoderma strain and the best temperature that produce the inhibiting effect on the pathogen growth. Local strain has the best behavior at 10 and 25°C.

Flow and thermal responses of aortic baroreceptors

1993 ◽  
Vol 70 (6) ◽  
pp. 2596-2605 ◽  
Author(s):  
P. A. Munch
Keyword(s):  
Aortic Arch ◽  
Neural Control ◽  
Effect Of Temperature ◽  
Wide Range ◽  
Activation Response ◽  
Flow Through ◽  
Effects Of Temperature ◽  
Aortic Arch Pressure ◽  
Aortic Baroreceptors

1. The aims of this study were 1) to determine whether the impulse activity in rabbit aortic baroreceptors (BRs) was influenced by changes in nonpulsatile flow through the aortic lumen and 2) to examine the BR and aortic arch responses to changes in temperature. 2. An in vitro aortic arch-aortic nerve preparation was used to record suprathreshold steady-state discharge in a total of 29 single-unit BRs from 12 New Zealand white rabbits. Changes in BR frequency were measured relative to control and were recorded simultaneously with aortic arch pressure, flow, temperature, diameter, and calculated wall shear stress (Sw). 3. With pressure held constant, stair-step increases in flow (3–18 ml/min) constricted the arch and evoked two types of BR responses: activation in most units (15 of 17 BRs tested) and inhibition in 2 units. The activation response appeared closely related to the changes in flow and Sw, but also appeared related to uncontrolled changes in perfusate temperature. 4. When the effects of temperature were examined more closely with pressure and flow held constant, controlled step increases in temperature (between 32 and 42 degrees C) constricted the arch and again evoked two BR responses: activation in 11 of 14 BRs tested and inhibition in 3 units. The Q10 for the activation response was 1.55 +/- 0.08 (mean +/- SE), which was not significantly different from the Q10 for activation when temperature varied with flow (1.65 +/- 0.1, P < 0.05). Thus the effect of temperature on most BRs was directionally and quantitatively similar in the presence and absence of changes in flow. 5. Last, when flow was examined over a wide range (15–515 ml/min) with temperature and pressure held constant, stair-step increases in flow failed to produce any change in BR frequency in each of 15 fibers tested (10 arches). The lack of response was not due to a functionally damaged preparation because the usual BR and aortic arch responses to pressure and to drug-evoked vasoconstriction (norepinephrine) and endothelial-mediated vasodilation (acetylcholine) were intact. 6. These results demonstrate that aortic BRs in rabbits are not sensitive to flow and thus are not likely influenced by fluctuations in cardiac output apart from associated changes in pressure. The aortic BRs are affected directly by variations in temperature and in some cases indirectly by temperature-related vasoconstriction. The effects of temperature may have important implications for neural control of the circulation when core temperature varies because of physiological and environmental stress.

EFFECT OF TEMPERATURE ON METABOLIC RATES OF LIVER AND BROWN FAT HOMOGENATES

1967 ◽  
Vol 45 (11) ◽  
pp. 1763-1771 ◽  
Author(s):  
Jane C. Roberts ◽  
Robert E. Smith
Keyword(s):  
Adipose Tissue ◽  
Oxygen Consumption ◽  
Brown Adipose Tissue ◽  
Brown Fat ◽  
Effect Of Temperature ◽  
Metabolic Rates ◽  
Brown Adipose ◽  
Rate Of Oxygen Consumption ◽  
Effects Of Temperature

The effects of temperature in vitro upon metabolic rates of homogenates of brown fat and liver from control and cold-acclimated rats have been examined over the range 10–37 °C. At all temperatures, brown adipose tissue exhibits a higher rate of oxygen consumption [Formula: see text] than does liver, α-ketoglutarate being used as substrate. At 10 °C, brown adipose tissue retains a larger percentage (36–38%) of its 37 °C metabolic rate than does liver (22–24%).Q10 values and energies of activation (Ea) have been determined and compared with other data reported for these tissues. At 20 °C, breaks appear in the Arrhenius plots for liver from both control and cold-acclimated rats and also for brown fat from control rats, but not for the brown fat from cold-acclimated rats. Thus brown adipose tissue from cold-acclimated rats retains relatively higher levels of respiration at temperatures below the 20 °C breaking point than does brown fat from control rats.In view of previously reported cold-induced increases in mass, vascularity, and [Formula: see text] of brown fat, this decreased temperature sensitivity in the cold-acclimated rats appears wholly consonant with the adaptive behavior of brown fat in its role as a thermogenic effector.

scholarly journals Selección de aislamientos de Trichoderma spp. in vitro como potenciales biofungicidas para el cont

Agriscientia ◽  
2020 ◽  
Vol 37 (2) ◽  
pp. 21-33
Author(s):  
Alejandro Andrés Pérez ◽  
M. A. Perez ◽  
B. Martinez Coca ◽  
I. N. Rollhaiser ◽  
M. C. Blengini
Keyword(s):  
Rhizoctonia Solani ◽  
Trichoderma Spp

La calidad y rendimiento en los sistemas de producción de papa se ve seriamente afectado por enfermedades por hongos como Rhizoctonia solani, cuyo control químico es ineficiente. El objetivo de este trabajo fue seleccionar aislamientos de Trichoderma spp. in vitro como potenciales biofungicidas para el control de R. solani en papa. A partir de muestras de suelo de los departamentos Calamuchita, Río Primero, Punilla y San Javier, de la provincia de Córdoba (Argentina), se aislaron e identificaron genéticamente 18 cepas nativas de Trichoderma. A través de cultivos duales in vitro se evaluó la competencia por el sustrato, micoparasitismo y capacidad de antibiosis. Se identificaron cinco cepas promisorias: T. atroviride ACp8 y CBa3, T. konigiopsis CBk2 y CBk4 y T. harzianum CBh2. Estas cepas presentaron un sobrecrecimiento mayor al 85 % sobre el patógeno; fueron muy competitivas por el sustrato (Grado 1) y presentaron una elevada capacidad de antibiosis mayor al 35 % lo que inhibió el crecimiento radial por al menos cuatro mecanismos de interacción hifal frente a R. solani. Las cepas seleccionadas que reconocen específicamente al fitopatógeno y presentan alta adaptación edafoclimática por su condición de nativas, podrán ser incorporadas al manejo del cultivo favoreciendo la sustentabilidad del sistema.

Influence of Glyphosate on Rhizoctonia Crown and Root Rot (Rhizoctonia solani) in Glyphosate-Resistant Sugarbeet

Weed Science ◽  
2012 ◽  
Vol 60 (1) ◽  
pp. 113-120 ◽  
Author(s):  
Kelly A. Barnett ◽  
Christy L. Sprague ◽  
William W. Kirk ◽  
Linda E. Hanson
Keyword(s):  
Rhizoctonia Solani ◽  
Ammonium Sulfate ◽  
Disease Severity ◽  
Root Rot ◽  
Radial Growth ◽  
Field Experiments ◽  
Herbicide Treatments ◽  
Tolerant Variety ◽  
Crown And Root Rot

Previous greenhouse studies with a noncommercial glyphosate-resistant sugarbeet variety indicated that susceptibility to Rhizoctonia crown and root rot could increase after glyphosate was applied. Greenhouse and field experiments were conducted in 2008 and 2009 to determine if glyphosate influenced disease severity in potential commercially available varieties of glyphosate-resistant sugarbeet. In the first greenhouse experiment in 2008, Hilleshög 9027RR, the most tolerant variety to Rhizoctonia crown and root rot, exhibited an increase in disease severity when glyphosate was applied. There were no significant differences between herbicide treatments in Hilleshög 9028RR, and glyphosate decreased disease severity in Hilleshög 9032RR when compared with the no-herbicide treatment. Experiments conducted to determine if glyphosate influenced Rhizoctonia solani growth in vitro indicated that glyphosate did not increase the radial growth of R. solani, except at 10× (190 µg ae ml−1) the normal rate of glyphosate plus ammonium sulfate (AMS). Field and additional greenhouse experiments were conducted using four commercial varieties. Differences in disease severity were observed when comparing varieties, but glyphosate did not significantly influence the severity of Rhizoctonia crown and root rot when compared with the no-herbicide control. Choosing a glyphosate-resistant sugarbeet variety with the best demonstrated tolerance to Rhizoctonia crown and root rot is an important factor in reducing disease severity and maintaining sugarbeet yield.

In-vitro bioefficacy of fungal antagonists against root rot of Pea caused by Rhizoctonia solani (Kuhn)

2018 ◽  
Vol 3 (02) ◽  
pp. 166-170
Author(s):  
Safdar Kaiser Hasmi ◽  
R. U. Khan
Keyword(s):  
Growth Inhibition ◽  
Rhizoctonia Solani ◽  
Root Rot ◽  
Radial Growth ◽  
Culture Technique ◽  
Dual Culture ◽  
Time Control ◽  
Trichoderma Koningii ◽  
Petri Plate

In-vitro effectiveness of various antagonistic fungi namely Aspergillus niger, A. flavus, Trichoderma koningii, T. atroviride, and T. harzianum were evaluated against Rhizoctonia solani by dual culture technique on potato dextrose agar. According to the observation recorded after 5 days, all the treatments were found to be superior over control (R. solani), but among all treatments A. niger was found to the most effective antagonist, with highest radial growth inhibition of the pathogen (77.01 percent), followed by A. flavus, T. harzianum and T. koningii i.e., 66.23, 64.42 and 62.20 percent. While as, T. atroviride was found to be the least effective one with minimum growth inhibition i.e., 42.21 percent. Whereas, at the same time control (R. solani) showed 100 percent radial growth and covered the whole Petri Plate within 5 days. All the bio-control agents were significantly effective to inhibit the sclerotia formation and development, except T. atroviride in which formation of sclerotia was recorded, while in all other treatments complete inhibition of sclerotia formation was recorded after 10 days of incubation.

Skeletal muscle fatigue in vitro is temperature dependent

1986 ◽  
Vol 61 (2) ◽  
pp. 660-665 ◽  
Author(s):  
S. S. Segal ◽  
J. A. Faulkner ◽  
T. P. White
Keyword(s):  
Effect Of Temperature ◽  
Isometric Contractions ◽  
Temperature Dependent ◽  
Temperature Optimum ◽  
Constant Frequency ◽  
Protocol Development ◽  
Effects Of Temperature ◽  
The Relationship ◽  
Bell Shaped Curve

Our purpose was to determine the effect of temperature on the fatigability of isolated soleus and extensor digitorum longus (EDL) muscles from rats during repeated isometric contractions. Muscles (70–90 mg) were studied at 20–40 degrees C in vitro. Fatigability was defined with respect to both the time and number of stimuli required to reach 50% of the force (P) developed at the onset of the fatigue test. Fatigue was studied during stimulation protocols of variable [force approximately 70% of maximum force (Po)] and constant frequency (28 Hz). Results for soleus and EDL muscles were qualitatively similar, but fatigue times were longer for soleus than for EDL muscles. During the variable-frequency protocol, development of approximately 70% of Po required an increase in stimulation frequency as temperature increased. During stimulation at these frequencies, fatigue time shortened as temperature increased. For both fatigue protocols, the relationship between temperature and the number of stimuli required to reach fatigue followed a bell-shaped curve, with maximum values at 25–30 degrees C. The temperature optimum for maximizing the number of isometric contractions to reach fatigue reflects direct effects of temperature on muscle function.

scholarly journals THE EFFECT OF CHITOSAN HYDROLYSATE ON THE FUNGI ALTERNARIA SOLANI, FUSARIUM SOLANI AND RHIZOCTONIA SOLANI IN VITRO

2021 ◽  
Vol 26 ◽  
pp. 200-209
Author(s):  
Balzhima Ts. Shagdarova ◽  
◽  
Natalia V. Karpova ◽  
Alla V. Il’ina ◽  
Valery P. Varlamov
Keyword(s):  
Molecular Weight ◽  
Nitric Acid ◽  
Rhizoctonia Solani ◽  
Fusarium Solani ◽  
Radial Growth ◽  
Alternaria Solani ◽  
Potato Dextrose Agar ◽  
Deacetylation Degree ◽  
Growth Experiments

Chitosan hydrolysate was obtained using nitric acid; the prevailing fraction had a molecular weight of 30 kDa and a deacetylation degree of 95%. The effect of chitosan hydrolysate when added to potato dextrose agar (PDA) in different concentrations (0.5, 1, 1.5, 2, 4, 6 and 8 mg/mL) was studied on the growth of the fungi Alternaria solani Sorauer, Fusarium solani (Mart.) Sacc. and Rhizoctonia solani J.G. Kühn. A. solani was the most sensitive to the addition of chitosan hydrolysate to PDA in radial growth experiments. On days 3 and 7 of incubation, the antifungal activity of the phytopathogen growth was 69%-92% and 69%-88%, respectively, in the concentration range of 0.5-2 mg/ml.

scholarly journals Temperature sensitivity differs between heart and red muscle mitochondria in mahi-mahi (Coryphaena hippurus)

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Gigi Y. Lau ◽  
Georgina K. Cox ◽  
John D. Stieglitz ◽  
Daniel D. Benetti ◽  
Martin Grosell
Keyword(s):  
Heart Mitochondria ◽  
Effect Of Temperature ◽  
Temperature Sensitive ◽  
Temperature Changes ◽  
Coryphaena Hippurus ◽  
Wide Range ◽  
Irreversible Effects ◽  
Effects Of Temperature ◽  
Lower Temperature

Abstract Maintaining energy balance over a wide range of temperatures is critical for an active pelagic fish species such as the mahi-mahi (Coryphaena hippurus), which can experience rapid changes in temperature during vertical migrations. Due to the profound effect of temperature on mitochondrial function, this study was designed to investigate the effects of temperature on mitochondrial respiration in permeabilized heart and red skeletal muscle (RM) fibres isolated from mahi-mahi. As RM is thought to be more anatomically isolated from rapid ambient temperature changes compared to the myocardium, it was hypothesized that heart mitochondria would be more tolerant of temperature changes through a greater ability to match respiratory capacity to an increase in temperature and to maintain coupling, when compared to RM mitochondria. Results show that heart fibres were more temperature sensitive and increased respiration rate with temperature increases to a greater degree than RM. Respiratory coupling ratios at the three assay temperatures (20, 26, and 30 °C), revealed that heart mitochondria were less coupled at a lower temperature (26 °C) compared to RM mitochondria (30 °C). In response to an in vitro acute temperature challenge, both tissues showed irreversible effects, where both heart and RM increased uncoupling whether the assay temperature was acutely changed from 20 to 30 °C or 30 to 20 °C. The findings from this study indicate that mahi-mahi heart mitochondria were more temperature sensitive compared to those from RM.

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