Lethal temperatures of citrus blackflyAleurocanthus woglumi [Hom.: Aleyrodidae] and its parasite,Amitus hesperidum [Hym.: Platygasteridae]

Entomophaga ◽  
1979 ◽  
Vol 24 (1) ◽  
pp. 35-39 ◽  
Author(s):  
R. H. Cherry
Keyword(s):  
Lethal Temperatures ◽  
Amitus Hesperidum

MICROECOLOGICAL FACTORS IN OYSTER EPIZOOTICS

1961 ◽  
Vol 39 (4) ◽  
pp. 449-485 ◽  
Author(s):  
Marshall Laird
Keyword(s):  
Crassostrea Virginica ◽  
Relevant Literature ◽  
Organic Pollution ◽  
Direct Effects ◽  
Ostrea Edulis ◽  
New Host ◽  
Lethal Temperatures ◽  
Canadian Data ◽  
Dead Animal ◽  
Favorable Conditions

On oyster beds as elsewhere, mud–water interfaces exhibit a biological film harboring saprobic microorganisms. The abundance of these is directly proportional to the amount of decomposing organic matter present. Different communities of protozoa and bacteria characterize each of the levels of organic pollution, which may be defined biologically in terms of a modification of the "Saprobiensystem" of Kolkwitz and Marsson. While the microorganisms concerned are not conspicuous on clean substrata except where especially favorable conditions are afforded certain of them by some dead animal or plant, their general abundance is indicative of pollution. This follows overaccumulation of reducible deposits, initiated by irregular tidal flushing, freshets, and winter icing, and rendering the microenvironment anaerobic. Ostrea edulis and Crassostrea virginica survive temporary exposure to the direct effects of such conditions as well as to near-lethal temperatures, but, weakened thereby, become vulnerable to invasion by saprobes from the enriched biological film. Unless environmental conditions improve before the oysters lose ability to recover, abnormal mortalities will be hastened by the activities of these microorganisms, notably Hexamita inflata (Protozoa). Relevant literature is reviewed, and possible local remedies are discussed. Canadian data are supported by original observations from Wales and Pakistan. Among other new host and locality records, Cristispira balbianii (Spirochaetales) and cercariae of a bucephalid trematode are listed from Ostrea belcheri from Karachi.

EFFECTS OF FLORIDA CITRUS PEST CONTROL PRACTICES ON THE CITRUS BLACKFLY (HOMOPTERA: ALEYRODIDAE) AND ITS ASSOCIATED NATURAL ENEMIES

1979 ◽  
Vol 111 (6) ◽  
pp. 731-734 ◽  
Author(s):  
George E. Fitzpatrick ◽  
Ronald H. Cherry ◽  
Robert V. Dowell
Keyword(s):  
Control Strategies ◽  
Integrated Control ◽  
Biological Control Agents ◽  
Chemical Treatments ◽  
Chronic Effects ◽  
Aleurocanthus Woglumi ◽  
Integrated Control Strategies ◽  
Florida Citrus ◽  
Amitus Hesperidum ◽  
Predator Complex

AbstractThe postbloom and summer sprays recommended in Florida commercial citrus cultures for management of insect and mite pests and phytopathogenic diseases caused a significant (P < 0.05) reduction of citrus blackfly, Aleurocanthus woglumi Ashby, infesting urban dooryard citrus. There were no observed adverse chronic effects on populations of the parasite Amitus hesperidum Silvestri, or the predator complex consisting of spiders, chrysopids, and coccinellids attributable to the chemical treatments. The absence of chronic pesticide-induced interference with biological control agents was interpreted as an indication of the potential for development of integrated control strategies against A. woglumi should this insect invade commercial citrus areas in Florida.

SOME LETHAL TEMPERATURE RELATIONS OF TWO MINNOWS OF THE GENUS CHROSOMUS

1966 ◽  
Vol 44 (3) ◽  
pp. 349-364 ◽  
Author(s):  
Albert V. Tyler
Keyword(s):  
Thermal Shock ◽  
High Temperatures ◽  
The Other ◽  
Lethal Temperature ◽  
Lethal Temperatures ◽  
Equal Temperature

The resistance and tolerance of Chrosomus eos and Chrosomus neogaeus to high temperatures were examined. Tests were conducted with C. neogaeus in winter and with C. eos in winter and summer. For both species, death at high temperatures could be separated into three lethal patterns or "effects". The first effect seemed to be associated, at least in part, with thermal shock. Factors generating the other effects were not apparent.Both species showed about the same degree of tolerance and resistance to high temperatures when they were acclimated to 15 °C or higher. At 9 °C, C. eos was less tolerant to high lethal temperatures than was C. neogaeus.When equal temperature acclimations were compared, C. eos was more resistant to high lethal temperatures in summer than in winter.

Power Ultrasound Treatment of Listeria monocytogenes in Apple Cider

2005 ◽  
Vol 68 (11) ◽  
pp. 2333-2340 ◽  
Author(s):  
ADAM R. BAUMANN ◽  
SCOTT E. MARTIN ◽  
HAO FENG
Keyword(s):  
Listeria Monocytogenes ◽  
Saline Solution ◽  
Bactericidal Effect ◽  
Solution Ph ◽  
Power Ultrasound ◽  
Apple Cider ◽  
Log Reduction ◽  
Lethal Temperatures ◽  
First Order Kinetics ◽  
Effects Of Temperature

Inactivation experiments with Listeria monocytogenes 10403S, an ultrasound-resistant strain, were conducted at sublethal (20, 30, and 40°C) and lethal (50, 55, and 60°C) temperatures in saline solution (pH 7.0), acidified saline solution (pH 3.4), and apple cider (pH 3.4) with and without application of ultrasound (20 kHz, 457 mW·ml−1). The survival of recoverable L. monocytogenes 10403S in apple cider was evaluated, and the effects of temperature, ultrasound, pH, and food matrix on inactivation were studied. Application of ultrasound increased the inactivation rate at both sublethal and lethal temperatures. Additional death of L. monocytogenes 10403S was due to low acidity at the lethal temperatures. The reduction in surviving L. monocytogenes 10403S followed first order kinetics at sublethal temperatures, but at lethal temperatures, a two-section linear model described the inactivation behavior. The bactericidal effect of thermosonication was additive in apple cider. The survival tests of L. monocytogenes 10403S in apple cider indicated the possibility of using a mild treatment condition in combination with ultrasound to achieve a 5-log reduction in number of listerial cells.

Aspects of the Physiology of Terrestrial Life in Amphibious Fishes

1969 ◽  
Vol 50 (1) ◽  
pp. 141-149 ◽  
Author(s):  
MALCOLM S. GORDON ◽  
INGE BOËTIUS ◽  
DAVID H. EVANS ◽  
ROSEMARY McCARTHY ◽  
LARRY C. OGLESBY
Keyword(s):  
Thermal Stresses ◽  
Severe Dehydration ◽  
Evaporative Water ◽  
Lethal Temperatures ◽  
Physiological Adaptations ◽  
Urea Production ◽  
Terrestrial Life ◽  
Production Increase ◽  
Amphibious Fishes ◽  
Environmental Temperatures

1. A study has been carried out of major aspects of the physiological adaptations for terrestrial life possessed by the amphibious mudskipper fish, Periophthalmus sobrinus, on the island of Nosy Bé, Madagascar. 2. These fish can survive for approximately 1½ days out of water, if not exposed to severe dehydration or thermal stresses. Evaporative water-loss rates while out of water are relatively low. Upper lethal temperatures are only a few degrees above normal midday environmental temperatures. 3. These fish lack the symptoms of the ‘diving syndrome’. Metabolic rates (oxygen consumption), heart rates, and blood lactic acid concentrations are not affected by shifts of fish between water and air. 4. Rates of ammonia and urea production increase in fish out of water. The ratio of urea/ammonia also increases. 5. The generality of the results, also their physiological significance, are discussed.

Hypoxial death inferred from thermally induced injuries at upper lethal temperatures, in the banded killifish, Fundulus diaphanus (LeSueur)

1977 ◽  
Vol 55 (10) ◽  
pp. 1705-1719 ◽  
Author(s):  
P. J. Rombough ◽  
E. T. Garside
Keyword(s):  
Cell System ◽  
Short Exposure ◽  
Temperature Sensitive ◽  
Thermally Induced ◽  
Lethal Temperatures ◽  
Ultimate Cause ◽  
The Central Nervous System ◽  
Trunk Musculature ◽  
Banded Killifish ◽  
Fundulus Diaphanus

Banded killifish, Fundulus diaphanus (LeSueur), acclimated to 25 °C were subjected to upper lethal temperatures using a 10 000 min bioassay procedure. The incipient upper lethal temperature (LT50) was about 34.5 °C. Histologic examination of heat-treated fish revealed no obvious injury to the heart, spleen, trunk musculature, eye, naris, integument, or digestive tract.Thermal stress induced progressive injury to the gills characterized by subepithelial edema, congestion of lamellar capillaries, and delamination of the respiratory epithelium from the pillar cell system. Areas of necrosis were observed in the lobus inferior of the hypothalamus and in the medulla oblongata. The pseudobranch epithelium was necrotic. Fatty change occurred in the liver. Acinar cells of the pancreas appeared autolytic and adjacent blood vessels damaged. Degenerative tubular changes and contracted glomerular tufts were noted in the kidney. The ovary was extremely temperature sensitive and displayed severe injury to oocytes and follicular cells after relatively short exposure to temperatures near the LT50.It is proposed that primary thermally induced injury is to the gills. This results in abnormal gas exchange and osmoregulation and leads to pathologic changes in other tissues. Hypoxia of the central nervous system appears to be the ultimate cause of death.

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