Effect Of Various Constant Temperatures Research Articles

Temperature-dependent development of Sesamia nonagrioides

The effect of various constant temperatures on survival, development and adult longevity of Sesamia nonagrioides Lefebvre (Lepidoptera: Noctuidae) was studied under laboratory conditions. The following temperatures were tested: 14, 17, 21, 25 and 31 °C. The percentage of individuals that completed development at each temperature as well as the days needed for the emergence of the pupa and adult eclosion were measured. Adult longevity was estimated under the same conditions. Development time decreased significantly with increasing temperature within the range 14–25 °C. Survival was higher at medium temperatures (17–25 °C) in comparison with that at more extreme temperature regimens (14 and 31 °C). Egg and first larval instars were the stages where S. nonagrioides suffered the highest mortality levels at all temperatures. The highest survival was recorded with experimental individuals aging between the third and fifth larval instar. Thermal requirements of development (developmental thresholds, thermal constant, optimum temperature) of S. nonagrioides were estimated with application of linear and one nonlinear models (Logan I). Upper and lower developmental thresholds ranged between 31.2 and 36.2 and 7.0 and 10.3 °C, respectively. The optimum temperature for development (where maximum rate of development occurs) was estimated at between 28.1 and 30.3 °C. The thermal constant for total development was estimated at 1,000.0 degree-days. Adult longevity was also affected by temperature, as it was significantly reduced at higher temperatures (21–31 °C) compared to the lower ones (14 and 17 °C). This information would be useful in determining the critical temperatures which may affect the distribution of S. nonagrioides concerning potential climate change.

Temperature-dependent survival, development, and adult longevity of the koinobiont endoparasitoid Venturia canescens (Hymenoptera: Ichneumonidae) parasitizing Plodia interpunctella (Lepidoptera: Pyralidae)

The effect of various constant temperatures on survival, development, and adult longevity of Venturia canescens Gravenhorst (Hymenoptera: Ichneumonidae) parasitizing larvae of Plodia interpunctella Hubner (Lepidoptera: Pyralidae) was studied under laboratory conditions. The following temperatures were tested: 15, 17.5, 20, 22.5, 25, 27.5, 30, and 32.5°C. The percentage of parasitoids that completed development at each temperature as well as the days needed for the emergence of the parasitoid’s pupa and adult eclosion was measured. Adult longevity was estimated under the same conditions. Survival of V. canescens was significantly higher at 25 and 27.5°C compared to 17.5, 20, 30, and 32.5°C. No individual of V. canescens managed to complete development at 15°C. Overall, developmental time decreased significantly with increasing temperature within the range of 17.5–27.5°C. The lowest developmental time was observed at 27.5°C while the highest at 17.5°C. Upper and lower threshold temperatures for total development were estimated at 36.2 and 13.2°C, respectively. Optimum temperature for development and thermal constant were 30.6°C and 312.5 degree days, respectively. Adult longevity was also affected by temperature, as it was significantly reduced at higher temperatures compared to the lower ones. This information would be useful in determining the potential of using V. canescens as a biological agent in IPM programs, by optimizing mass rearing and release techniques of the parasitoid.

GA3 and Proline Promote Germination of Wheat Seeds by Stimulating α-Amylase at Unfavorable Temperatures

abstractThe effects of various constant temperatures (4, 9, 14, 19, 24, 29, 34, and 38°C) on the germination of winter wheat seed ( Triticum aestivum L. cv. ‘Koyuki’) in a dark condition were studied. The maximum germination percentage was 98% at 24°C. The speed of germination was fastest at 29°G. These results indicate that the most suitable temperature for germination was in the range of 24 to 29°G. α-Amylase expression during germination was also high at higher temperature, and maximum expression occurred at 29°C, although a high temperature of 38°C prevented the synthesis of α-amylase. The close correlation between germination and α-amylase activity at various temperatures indicates that α-amylase is an essential factor for the temperature-dependent germination of wheat seed. In contrast, accumulation of proline increased at a lower temperature, and was the highest at 4°G. We also studied the effects of gibberellin (GA3) and proline, a compatible osmotica in alleviating the effect of low and high temperature stresses. Pre-soaking treatment with GA3 and proline was effective in promoting germination and increasing α-amylase expression at a low (4°C) and high (38°C) temperature. These results suggest that GA3 and proline exhibit positive effects on stress alleviation through the stimulation of α-amylase expression.

Effects of Temperature on Longevity, Reproduction, and Development of the Asparagus Aphid (Homoptera: Aphididae) and the Parasitoid, Diaeretiella rapae (Hymenoptera: Braconidae)

The effects of various constant temperatures on longevity, fecundity, reproductive rate, and developmental rate of the asparagus aphid, Brachycorynella asparagi Mordvilko, and its parasitoid, Diaeretiella rapae (M'Intosh), were investigated. Moderate temperatures (23°C) were optimal for aphid survival and reproduction. Similarities in aphid biology between Michigan and Washington, where the aphid is a severe pest, suggest that the difference in pest status between the two states is not attributable to biotype differences. D. rapae reproductive and developmental rates were highest at 30°C, but longevity was reduced considerably, reducing total fecundity. Temperature responses suggest that biotype differences are present between this population and other D. rapae populations reported in the literature. Results do not indicate what factors limit D. rapae effectiveness in the field.

Mathematical model for creep and thermal shrinkage of concrete at high temperature

Based on the existing limited test data, it is possible to set up an approximate constitutive model for creep and shrinkage at temperatures above 100°C, up to about 400°C. The model presented here describes the effect of various constant temperatures on the creep rate and the rate of aging, similar effects of the specific water content, the creep increase caused by simultaneous changes in moisture content, the thermal volume changes as well as the volume changes caused by changes in moisture content (drying shrinkage or thermal shrinkage), and the effect of pore pressure produced by heating. Generalizations to time-variable stresses and multiaxial stresses are also given. The model should allow more realistic analysis of nuclear reactor vessels and containments for accident situations, of concrete structures subjected to fire, of vessels for coal gassification or liquefaction, etc.

The effect of temperature on development and the histology of the neuroendocrine system of the tettigoniid, Jamaicana flava (Caudell)

The effect of various constant temperatures on the rate of development and histology of the neuroendocrine system have been studied in sixht instar larvae of Jamaicana flata. Changes in the histology of the neuroendocrine system are discussed in relation to parallel changes in the rate of development.

Effect of Temperature on Development of the Free-Living Stages of Ostertagia ostertagi

Hatching of the eggs of Ostertagia ostertagi was studied by recovering them from feces and incubating them in distilled water at temperatures between 4 and 40 C. The hatching occurred at temperatures between 4 and 35 C. The rate of development increased with the rise of the temperature. The development of the infective larvae was studied in fecal cultures. The infective larvae developed between 10 to 35 C. The optimum temperature for development was 25 C. The speed of development increased with the rise of temperature but the percentage recovery decreased at higher and lower temperatures. The size of the newly hatched larvae varied with the temperature at which they developed, being biggest at 15 C and smallest at 35 C. The size of the infective larvae grown at different temperatures varied. The maximum size was at 20 C and it decreased at temperatures above or below this. Like other trichostrongylid nematodes, Ostertagia ostertagi, which inhabits the abomasum of cattle, passes a part of its life cycle as freeliving stages outside the host. During their free existence these stages are subject to the effects of a large number of biotic and climatic factors existing in their microenvironment. From field experiments it is difficult to assess the importance or effect of individual factors and therefore the investigator must resort to controlled laboratory experiments. Temperature is one of the most important factors in the development of the free-living stages. Rose (1961, 1962) and Kutzer (1967) made some observations on the effect of temperature on the development of free-living stages of 0. ostertagi but since their primary interests were to study the ecology of these stages, their observations were of a very limited nature. The objective of the study reported here was to observe the effects of various constant temperatures on the development of the free-living stages of 0. ostertagi. MATERIALS AND METHODS A pure monospecific infection of 0. ostertagi was established in a worm-free calf by administering the infective larvae. For all experiments feces were collected directly from the rectum between 30 to 60 days after administration of the infective larvae to the calf.

Influence of Temperature on Development and Reproduction of Geocoris atricolor, G. pallens, and G. punctipes (Heteroptera: Lygaeidae) from California

The effects of various constant temperatures on development of eggs and nymphs and on fecundity and fertility of G. atricolor Montandon, G. pallens Stal, and G. punctipes (Say) are presented. Eggs and nymphs of all species failed to complete development at 37.8°C. The egg incubation period decreased with increased temperature and was consistently shorter for G. pallens and consistently longer for G. punctipes at each temperature tested. The duration of the nymphal stages also decreased with increased temperature, but at 23.9°C, G. punctipes developed in the shortest time and G. pallens developed in the longest time. At the other temperatures tested the duration of nymphal stages followed the same order as eggs (G. pallens < G. atricolor < G. punctipes). Oviposition and fertility were maximal in G. atricolor and G. punctipes at 32.2°C. Oviposition by G. pallens was maximal at 35.0°C. Females of G. atricolor and G. pallens, but not G. punctipes, oviposited at 35.0°C. At 23.9°C, only females of G. punctipes oviposited.

Comparative Studies of Circadian Locomotory Rhythms in Four Species of Terrestrial Crabs

Spontaneous locomotor behavior of four species (Gecarcinus lateralis, Cardisoma guanhumi, Ocypode quadrata, Coenobita clypeatus) of land crabs was studied in the field and in controlled conditions in the laboratory. All were found to be predominantly nightactive, and these locomotor rhythms persisted in constant temperature and in both constant darkness or constant illumination of various intensities for periods of over 3 months. No difference in the circadian period length of the rhythm could be distinguished at constant light intensities between 5 and 50 ft-c. The rhythms could be rephased by subjecting the crabs to artificial light cycles offered out of phase with the natural one. The effect of various constant temperatures (all within the ecological range) on the period lengths of rhythms in two species of crabs was tested; the rhythms were found to be essentially independent of temperature. The great edible land crab reacted differently to increases in temperature in that the length of its period increased slightly, producing a Ql0 of 0.996. I

The Effects of Various Constant Temperatures on the Development of the Free Living-Stages of Some Nematode Parasites of Cattle

The eggs and larvae of Cooperia punctata, C. oncophora, Ostertagia ostertagi, Trichostrongylus axei, and T. colubriformis displayed a similar rate of development in fecal cultures at various constant temperatures. In general, the rate of development for the five species accelerated as the temperature increased. There was an appreciable variability in the rate of embryonic and larval development in any one culture. The optimal temperature, based on the rate of development and percentage of eggs developing into infective larvae, was 25 C. No development beyond the gastrula stage occurred below 6 C. Above 32 C, development was faster than at lower temperatures, but mortality rate of the preinfective stages was very high. Various ecologic factors regulate the bionomics of the free-living stages of nematodes (Wallace, 1961). Of these factors, the temperature of the microenvironment has the greatest effect on rate of embryonation and development of the larvae of nematodes parasitic in cattle. Information on the effects of temperature on development has dealt primarily with Haemonchus contortus (Berberian and Mizelle, 1957; Silverman and Campbell, 1959). Data are also available on Ostertagia ostertagi (Rose, 1961) and Trichostrongylus spp. (Dinaburg, 1945; Silverman and Campbell, 1959). Results of investigations with other species of parasitic nematodes not covered in this work have also been reported, but most of them had primary interests other than the effects of temperature. The study reported here deals with the effects of various constant temperatures on the development of the free-living stages of Cooperia punctata, Cooperia oncophora, Ostertagia ostertagi, Trichostrongylus axei, and Trichostrongylus colubriformis. Some of these data have been presented in an abstract (Ciordia and Bizzell, 1960). MATERIALS AND METHODS To minimize the variables which characterize fecal cultures, each series of experiments was conducted with freshly voided feces from one calf. At least ten series of experiments were conducted at each of the temperatures studied. Each experiment consisted of from 3 to 18 replicate cultures at each of the temperatures, depending on the amount of feces available at that time. Feces were obtained from dairy calves with experimental monospecific infections of C. punctata, C. oncophora, O. ostertagi, T. axei, and T. colubriformis. Feces were also obtained from calves harboring mixed infections of these nematode species. The calves were kept in separate portable pens on a concrete floor, which was washed thoroughly daily. They were maintained on a ration of alfalfa hay ad lib. and 1 lb of grain/day. Freshly voided feces were thoroughly mixed, whereupon 10-g samples were taken out for routine nematode egg counts. When necessary, enough water was added to the feces to standardize the consistency to approximate that of normal feces (60 to 70% moisture). Feces for each series of experiments were divided into 100-g samples which were placed in 8 oz waxed paper cups (Lily-Tulip Cup Corp., No. 8S) and covered with snap-over lids (No. 16S-16) before being placed in constant temperature cabinets (low temperature incubators, mechanical convection, range 5 to 50 C, accuracy of ?1.0 C). Temperatures used were: 5, 10, 15, 20, 25, 32, 35, and 40 C. In addition, some cultures were incubated at 6 and 8 C to determine the lowest temperature at which larvae would develop. Cultures were kept moist by the periodic addition of water. This was necessary even though Received for publication 23 July 1962. * In cooperation with the Georgia Agricultural Experiment Station. Station Journal Series No. 424. Portions of this study were conducted as part of Southern Regional Project (S-21)-a cooperative study involving agricultural experiment stations in the Southern Region.