Author Keywords: Freezing model; freeze tolerance; ice content; supercooling; cold tolerance; calorimetry 相似文献
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1.
1. 1.Although body ice content is an important variable affecting freeze tolerance, present calorimetric methods for its measurement necessarily require the termination of a freezing protocol.
2. 2.A simple iterative model, based on the colligative properties of solutions and requiring precise measurements of only equilibrium freezing point (of the unfrozen organism) and of core body temperature, allows estimation of the percentage of body water frozen at any time during a freezing episode.
3. 3.This model can also predict the lethal temperature for a freezing ectotherm, assuming that death occurs due to osmotic dehydration when 67% (of any other known lethal fraction) of the body water is frozen.
4. 4.The basic model is easily extended to evaluate the effects of variables such as: body mass, initial body water content, initial osmotic concentration, and test chamber microenvironment.
5. 5.This model is not intended to supplant existing more exact biophysical models of freezing kinetics. Rather it is proposed as a first approximation which is generally supported by published data and which should be of significant practical value for investigators of freeze tolerant organisms.
2.
Abstract. Typhlodromips montdorensis has potential for release as a glasshouse biological control agent in the U.K. against thrips and spider mites. This study investigates the field survival in the U.K. of T. montdorensis when released as eggs, and the diapause response when reared in a regime related to its location of origin. All acclimated and nonacclimated eggs of T. montdorensis die in the field within 7 days of exposure. It is not possible to induce diapause in T. montdorensis reared at 21 °C under a LD 11 : 13 h photoperiod. The results presented here support the view that T. montdorensis is unlikely to survive a U.K. winter outside of the glasshouse environment, and contribute to the understanding of the biology of this little known species. 相似文献
3.
Abstract. Larvae of the hoverfiy Episyrphus balteatus (DeGeer) are important predators of aphids in the U.K. A large proportion of the U.K. population migrates south to warmer climes at the end of summer, but a small number are thought to overwinter in the U.K., with the mated female being the overwintering morph. The cold tolerance of adult flies was investigated to assess the overwintering potential of E. balteatus in the U.K. The high supercooling point (SCP) of -8.3 ± 0.7°C, and lethal temperature (LTemp30 ) of -9.1°C for acclimated females suggest that E. balteatus has limited cold hardiness. This was confirmed by experiments where, despite a strong acclimation response in both males and females, there was no long-term survival at 5, 0 or - 5°C. At 5°C, 90% of females had died after 10 days. The weak cold hardiness of adult E. balteatus was corroborated by field experiments which demonstrated a 100% mortality after 10 weeks' exposure to U.K. winter conditions. The ecological significance of this limited cold hardiness is discussed in relation to the overwintering abilities of E. balteatus in the U.K. 相似文献
4.
John G. Duman 《Journal of insect physiology》1984,30(3):235-239
Overwintering larvae of the Cucujid beetle, Cucujus clavipes, were freeze tolerant, able to survive the freezing of their extracellular body fluids, during the winter of 1978–1979. These larvae had high levels of polyols (glycerol and sorbitol), thermal hysteresis proteins and haemolymph ice nucleators that prevented extensive supercooling (the supercooling points of the larvae were ? 10°C), thus preventing lethal intracellular ice formation. In contrast, C. clavipes larvae were freeze suspectible, died if frozen, during the winter of 1982–1983, but supercooled to ～ ? 30°C. The absence of the ice nucleators in the 1982–1983 larvae, obviously essential in the now freeze-susceptible insects, was the major detected difference in the larvae from the 2 years. However, experiments in which the larvae were artifically seeded at ? 10°C (the temperature at which the natural haemolymph ice nucleators produced spontaneous nucleation in the 1978–1979 freeze tolerant larvae) demonstrated that the absence of the ice nucleators was not the critical factor, or at least not the only critical factor, responsible for the loss of freeze tolerance in the 1982–1983 larvae. The lower lethal temperatures for the larvae were approximately the same during the 2 winters in spite of the change in overwintering strategy. 相似文献
5.
对于分布在温带和寒带的线虫,它们只有战胜冬季寒冷的挑战,才能有利于种群的存在与发展。因此,耐寒性是线虫生物学研究中不可忽视的内容。综述了关于线虫在低温胁迫下的耐寒性测定方法、耐寒对策及耐寒机制等方面的研究进展。线虫的耐寒性和昆虫一样,可通过过冷却点和低温存活率两种指标进行评价,但在具体的实验方法上,线虫耐寒性研究有其不同之处。线虫的耐寒对策和耐寒机制具有多样化。耐寒对策主要有耐冻和避冻,二者能共同渗透于线虫的耐寒过程中。耐寒机制包括特殊发育阶段的形成、低温驯化作用、低分子量抗冻物质的聚集、以及高分子量抗冻蛋白和热休克蛋白的产生,等等。此外,还强调应从多个角度研究线虫的耐寒性,如寒冷敏感型线虫的研究、寄生线虫的耐寒对策研究以及交叉胁迫的研究。 相似文献
6.
Sinclair BJ Addo-Bediako A Chown SL 《Biological reviews of the Cambridge Philosophical Society》2003,78(2):181-195
Insects may survive subzero temperatures by two general strategies: Freeze-tolerant insects withstand the formation of internal ice, while freeze-avoiding insects die upon freezing. While it is widely recognized that these represent alternative strategies to survive low temperatures, and mechanistic understanding of the physical and molecular process of cold tolerance are becoming well elucidated, the reasons why one strategy or the other is adopted remain unclear. Freeze avoidance is clearly basal within the arthropod lineages, and it seems that freeze tolerance has evolved convergently at least six times among the insects (in the Blattaria, Orthoptera, Coleoptera, Hymenoptera, Diptera and Lepidoptera). Of the pterygote insect species whose cold-tolerance strategy has been reported in the literature, 29% (69 of 241 species studied) of those in the Northern Hemisphere, whereas 85 % (11 of 13 species) in the Southern Hemisphere exhibit freeze tolerance. A randomization test indicates that this predominance of freeze tolerance in the Southern Hemisphere is too great to be due to chance, and there is no evidence of a recent publication bias in favour of new reports of freeze-tolerant species. We conclude from this that the specific nature of cold insect habitats in the Southern Hemisphere, which are characterized by oceanic influence and climate variability must lead to strong selection in favour of freeze tolerance in this hemisphere. We envisage two main scenarios where it would prove advantageous for insects to be freeze tolerant. In the first, characteristic of cold continental habitats of the Northern Hemisphere, freeze tolerance allows insects to survive very low temperatures for long periods of time, and to avoid desiccation. These responses tend to be strongly seasonal, and insects in these habitats are only freeze tolerant for the overwintering period. By contrast, in mild and unpredictable environments, characteristic of habitats influenced by the Southern Ocean, freeze tolerance allows insects which habitually have ice nucleators in their guts to survive summer cold snaps, and to take advantage of mild winter periods without the need for extensive seasonal cold hardening. Thus, we conclude that the climates of the two hemispheres have led to the parallel evolution of freeze tolerance for very different reasons, and that this hemispheric difference is symptomatic of many wide-scale disparities in Northern and Southern ecological processes. 相似文献
7.
Abstract The responses of overwintering larvae of the pine needle gall midge Thecodiplosis japonensis Uchida et Inouye to rapid cold hardening and cold acclimation were studied. A rapid cold hardening response is found in the 3rd instar larvae of T. japonensis. When overwintering larvae are transferred directly from 27°C to ‐ 15°C for 3 h, there is only 17.9% survival, whereas exposure to 4°C for 2 h prior to transfer to ‐ 15°C increases survival to 40.0%. The acquired cold tolerance is transient and is rapidly lost (after 15 min at 27°C). Rapid cold hardening is more effective in maintaining larval survival than cold acclimation. Different mechanisms are suggested to regulate the insect's cold hardiness under rapid cold hardening and cold acclimation. 相似文献
8.
快速冷耐受比冷驯化更能提高越冬松针瘿蚊 (Thecodiplosis japonensis)幼虫的耐寒力(英文) 总被引：4，自引：0，他引：4
松针瘿蚊以三龄老熟幼虫在浅层土表越冬。本文比较两种温度处理过程 ,快速冷耐受 (rapidcoldhardening)和冷驯化 (coldacclimation)对松针瘿蚊获得耐寒性的能力。发现 3龄越冬幼虫具有一种特殊的生物学现象 -快速冷耐受。当越冬幼虫直接从 2 7℃转入 - 1 5℃ 3小时 ,其存活率仅为 1 7 9% ,然而在 - 1 5℃暴露之前 ,经 4℃ ,2h短暂处理 ,其存活率升高至 40 0 % ,而短时间 (1 5分钟 ) 2 7℃能抑制快速冷耐受的表达。快速冷耐受比冷驯化更能提高越冬松针瘿蚊幼虫的耐寒力。文中还讨论了快速冷耐受和冷驯化提高松针瘿蚊耐寒能力的不同机制 相似文献
9.
George D. Yocum Karl H. Joplin David L. Denlinger 《Archives of insect biochemistry and physiology》1991,18(4):239-249
Diapausing pharate first instars of the gypsy moth, Lymantria dispar, respond to high temperature (37–41°C) by suppressing normal protein synthesis and synthesizing a set of seven heat shock proteins with Mrs of 90,000, 75,000, 73,000, 60,000, 42,000, 29,000, and 22,000 as determined by SDS-PAGE. During recovery at 25°C from heat shock, synthesis of the heat shock proteins gradually decreases over a period of 6 h, while normal protein synthesis is restored. A subset of these same heat shock proteins is also expressed during recovery at 4°C or 25°C from brief exposures to low temperature (-10 to 20°C), and its expression is more intense with increased severity of cold exposure. During recovery at 4°C after 24 h at ?20°C, both 90,000 and 75,000 Mr heat shock proteins are expressed for more than 96 h. While normal protein synthesis is suppressed during heat shock and recovery from heat shock, normal protein synthesis coincides with synthesis of the heat shock proteins during recovery from low temperatures, thus implying that expression of the heat shock proteins is not invariably linked to suppression of normal protein synthesis. Western transfer, using a monoclonal antibody that recognizes the inducible form of the human 70,000 Mr heat shock protein, demonstrates that immunologically related proteins in the gypsy moth are expressed at 4°C and during recovery from cold and heat shock. 相似文献
10.
11.
Alexandra Montoya-Cruz;Ronald A. Díaz-Flórez;Juan Manuel Carvajalino-Fernández; 《Austral ecology》2024,49(9):e13578
High Andean lizards in the Andes face numerous challenges in high-altitude environments characterized by significant temperature, spatial and temporal variations. These factors greatly influence their thermal characteristics and adaptive strategies for coping with temperature fluctuations. This study aims were to investigate the thermal biology of high mountain lizards (>2000 m) inhabiting the Andes Mountain range, using information from existing literature, and to identify the potential impacts of the original climate change scenarios developed in this study. Within the Andes, high-altitude species are primarily found in families like Liolaemidae, Gymnophthalmidae, Tropiduridae, Anolidae and Leiourisauridae. Notably, we found in the literature that the higher body temperatures and maximum critical temperatures in southern species compared to those closer to the tropics. Typically, diurnal and seasonal temperature variations have a significant impact on the body temperature of these high-altitude lizards, but their adaptive behaviours and physiological mechanisms enhance their resistance to extreme temperatures. Populations situated below the equator often exhibit higher body temperatures and maximum critical temperatures, largely due to their exposure to higher ambient temperatures during summer. With all global warming scenarios indicating temperature increases in latitudinal regions, tropical high-altitude lizards, historically less thermally adaptable, may be particularly susceptible to these temperature rises. It is crucial to consider that additional factors, such as species activity patterns, thermal resource availability and diminishing suitable thermal habitats, will also play a pivotal role in shaping the future of these lizard species, making the situation even more complex and challenging. 相似文献
12.
To evaluate the suitability of using ice nucleation active (INA) bacteria for the biological control of insect pests, the supercooling point (SCP) of larvae of mulberry pyralid,Glyphodes duplicalis,and silkworm,Bombyx mori,ingesting INA strains ofErwinia(Pantoea)ananasandPseudomonas syringaewas determined. Mean SCP of the guts of silkworm larvae ingesting INA strains ofE. ananasranged from −2.5 to −2.8°C, being 5°C higher than that in control treatments. Similarly, mean SCP of mulberry pyralid larvae ingesting INA strain ofE. ananas,which can grow well in the gut, was −4.7°C at 3 days after treatment, being 6.5°C higher than that in control treatments. On the other hand, mean SCP of the larvae-ingesting INA strain ofP. syringae,which cannot grow in the gut, was −9.0°C at 3 days after treatment, rising by only 2.5°C higher than that in the control treatments. In addition, more than 80% of the larvae of mulberry pyralid ingesting the INA strain ofE. ananasfroze and eventually died when exposed to −6°C for 18 h, while only 36% of the larvae ingesting the INA strain ofP. syringae,or approximately 20% of the control larvae, froze and died. Thus, the gut colonization by INA strains ofE. ananasreduced remarkably the cold hardiness of the insects. These findings suggest that INA strains ofE. ananascould be effective as a potential biological control agent of insect pests. 相似文献
13.
Rolv Lundheim 《Journal of phycology》1997,33(5):739-742
The ice nucleation temperatures of thallus fragments of different macroalgal species were investigated. The samples were collected from the littoral zone on a rocky shore in Trondheimsfjord, central Norway. Thallus fragments of species growing in the upper parts of the eulittoral zone had lower ice nucleation temperatures than those of species living in the lower eulittoral zone and in the upper sublittoral zone. Samples collected in the winter had lower nucleation temperatures than samples from the same species collected in the summer, which indicates that the seaweeds are removing or inactivating ice nucleators as a part of their cold hardiness strategy. 相似文献
14.
Valeria Lencioni Olivier Jousson Graziano Guella Paola Bernabò 《Physiological Entomology》2015,40(1):43-53
Insects inhabiting cold streams must either tolerate or avoid freezing to survive. The present study reports the strategy adopted by fourth‐instar larvae of two chironomid species [Pseudodiamesa branickii (Nowicki) and Diamesa cinerella (Meigen)] overwintering in a glacial stream (in the Italian Alps). The cold adaptive potential of both species under acute cold stress is investigated down to –30 °C. Supercooling points, lower lethal temperatures (LLTs), haemolymph thermal hysteresis, whole body content of sugars and polyols, and the expression of heat shock protein (HSP) genes (hsc70 and hsp70) expression are estimated. Comparable thermal hysteresis (> 2 °C) is measured in the two species, both of which accumulate glucose and sucrose as the main cryoprotectants. According to the supercooling points (= –6.37 and –6.85 °C, respectively) and LLT100 (= –16.2 and –14.7 °C, respectively), P. branickii and D. cinerella can both be considered as freeze tolerant. However, the cumulative proportion of individual freezing values and the LLT50 (–9.14 and –6.13 °C, respectively) suggest that P. branickii is more cold hardy than D. cinerella, whereas the gene expression data (i.e. an absence of up‐regulation of hsp70 in D. cinerella) suggest that D. cinerella is more cold hardy than P. branickii. These findings are discussed in relation to the validity of the different metabolic indicators for defining the level of cold hardiness of a species, even in relation to its cold stenothermy. The results are also discussed in relation to climate warming, which represents a serious threat for species from glacier‐fed streams. 相似文献
15.
Lisa G. Neven Dale W. Haskell Andrea Hofig Qui-Bao Li Charles L. Guy 《Plant molecular biology》1993,21(2):291-305
16.
Gbor Vtek Veronika Fekete Mrta Ladnyi Elena Cargnus Pietro Zandigiacomo Richrd Olh Martin Schebeck Axel Schopf 《Agricultural and Forest Entomology》2020,22(3):231-237
- The invasive sawfly Aproceros leucopoda causes severe defoliation of various elm species and thus can be a major pest in forest stands and urban environments.
- The overwintering biology of A. leucopoda has not been investigated so far; therefore, the aim of this study was to determine the cold tolerance strategy and cold hardiness of hibernating A. leucopoda eonymphs.
- The supercooling points (SCPs) of overwintering individuals varied geographically, monthly and interannually and ranged between ?12.14 °C and ?24.22 °C.
- As none of the eonymphs survived once the SCP had been reached, A. leucopoda is classified as a freeze‐avoidant species.
- Survival rates of overwintering eonymphs exposed to different sub‐zero temperatures above the SCP (?1.6 °C and ?4.0 °C for 10, 20 and 30 days and ?10.5 °C for 9 days) ranged between 89.2% and 100%, suggesting that A. leucopoda is not a chill‐susceptible species.
- Our results suggest that low winter temperatures may not be expected to be an important limiting factor for the overwintering success of A. leucopoda.
17.
Evergestis extimalis (Scopoli) is a pest insect present in spring rape fields of the Qinghai–Tibet plateau. A survey of its distribution and analysis of its physiological and biochemical variances of its overwintering larvae were conducted in this study. Prior to 2006, Evergestis extimalis Scopli appeared only sporadically at the east agricultural district of Qinghai Province at 2,100 m elevation; after 2006, there have been frequent outbreaks at 2,200 m or so height. The insect's distribution has extended continuously toward higher altitudes yearly, and the scope of its damage reached 2,800 m height in 2010. These changes indicate that the cold hardiness of E. extimalis is on the rise. Physiological and biochemical analyses were performed for the insect's overwintering larvae from November 2011 to March 2012. The supercooling point (SCP) and freezing point (FP) ranged from ?6.85°C to ?12.49°C and from ?6.23°C to ?8.17°C, respectively, and both were at their respective lowest points in January 2012; the lowest points of water and fat contents (which did not vary to any extreme degree throughout the test period) were also observed in January 2012. Glycogen content varied from 2.42 mg/g to 4.56 mg/g. Protein content increased gradually at the first two months and reached its peak in January 2012 before dropping slightly. The activity of protective enzymes POD, CAT, and SOD varied with changes in environmental temperature, and each was at its lowest point in January 2012. With the exception of protein and glycerol content, other physiological and biochemical variances were generally parallel with environmental temperature, strongly indicating that E. extimalis has indeed developed cold hardiness. 相似文献
18.
ABSTRACT.
- 1 Cold hardiness as measured by supercooling ability in the active stages of the grain aphid Sitobion avenae (F.) decreased progressively with maturation.
- 2 Aphids showed no acclimation response when maintained at low temperatures.
- 3 Starvation did not improve supercooling ability.
- 4 In a single exposure, surface moisture caused inoculation above the inherent supercooling point in a small proportion of a population.
- 5 Field populations show a seasonal change in supercooling ability, which is at a maximum in summer and a minimum in late winter.
- 6 It is concluded that the act of feeding on healthy plant tissue may confer extensive supercooling ability.
19.
Kerri L. Coon Kevin J. Vogel Mark R. Brown Michael R. Strand 《Molecular ecology》2014,23(11):2727-2739
Field studies indicate adult mosquitoes (Culicidae) host low diversity communities of bacteria that vary greatly among individuals and species. In contrast, it remains unclear how adult mosquitoes acquire their microbiome, what influences community structure, and whether the microbiome is important for survival. Here, we used pyrosequencing of 16S rRNA to characterize the bacterial communities of three mosquito species reared under identical conditions. Two of these species, Aedes aegypti and Anopheles gambiae, are anautogenous and must blood‐feed to produce eggs, while one, Georgecraigius atropalpus, is autogenous and produces eggs without blood feeding. Each mosquito species contained a low diversity community comprised primarily of aerobic bacteria acquired from the aquatic habitat in which larvae developed. Our results suggested that the communities in Ae. aegypti and An. gambiae larvae share more similarities with one another than with G. atropalpus. Studies with Ae. aegypti also strongly suggested that adults transstadially acquired several members of the larval bacterial community, but only four genera of bacteria present in blood fed females were detected on eggs. Functional assays showed that axenic larvae of each species failed to develop beyond the first instar. Experiments with Ae. aegypti indicated several members of the microbial community and Escherichia coli successfully colonized axenic larvae and rescued development. Overall, our results provide new insights about the acquisition and structure of bacterial communities in mosquitoes. They also indicate that three mosquito species spanning the breadth of the Culicidae depend on their gut microbiome for development. 相似文献
20.
In temperate regions, an organism's ability to rapidly adapt to seasonally varying environments is essential for its survival. In response to seasonal changes in selection pressure caused by variation in temperature, humidity, and food availability, some organisms exhibit plastic changes in phenotype. In other cases, seasonal variation in selection pressure can rapidly increase the frequency of genotypes that offer survival or reproductive advantages under the current conditions. Little is known about the relative influences of plastic and genetic changes in short‐lived organisms experiencing seasonal environmental fluctuations. Cold hardening is a seasonally relevant plastic response in which exposure to cool, but nonlethal, temperatures significantly increases the organism's ability to later survive at freezing temperatures. In the present study, we demonstrate seasonal variation in cold hardening in Drosophila melanogaster and test the extent to which plasticity and adaptive tracking underlie that seasonal variation. We measured the post‐cold hardening freeze tolerance of flies from outdoor mesocosms over the summer, fall, and winter. We bred outdoor mesocosm‐caught flies for two generations in the laboratory and matched each outdoor cohort to an indoor control cohort of similar genetic background. We cold hardened all flies under controlled laboratory conditions and then measured their post‐cold hardening freeze tolerance. Comparing indoor and field‐caught flies and their laboratory‐reared G1 and G2 progeny allowed us to determine the roles of seasonal environmental plasticity, parental effects, and genetic changes on cold hardening. We also tested the relationship between cold hardening and other factors, including age, developmental density, food substrate, presence of antimicrobials, and supplementation with live yeast. We found strong plastic responses to a variety of field‐ and laboratory‐based environmental effects, but no evidence of seasonally varying parental or genetic effects on cold hardening. We therefore conclude that seasonal variation in post‐cold hardening freeze tolerance results from environmental influences and not genetic changes. 相似文献