共查询到20条相似文献,搜索用时 203 毫秒
1.
Hayashi M Wharton DA 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》2011,181(3):335-342
The cold tolerance abilities of only a few nematode species have been determined. This study shows that the oatmeal nematode,
Panagrellus redivivus, has modest cold tolerance with a 50% survival temperature (S
50) of −2.5°C after cooling at 0.5°C min−1 and freezing for 1 h. It can survive low temperatures by freezing tolerance and cryoprotective dehydration; although freezing
tolerance appears to be the dominant strategy. Freezing survival is enhanced by low temperature acclimation (7 days at 5°C),
with the S
50 being lowered by a small but significant amount (0.42°C). There is no cold shock or rapid cold hardening response under the
conditions tested. Cryoprotective dehydration enhances the ability to survive freezing (the S
50 is lowered by 0.55°C, compared to the control, after 4 h freezing at −1°C) and this effect is in addition to that produced
by acclimation. Breeding from survivors of a freezing stress did not enhance the ability to survive freezing. The cold tolerance
abilities of this nematode are modest, but sufficient to enable it to survive in the cold temperate environments it inhabits. 相似文献
2.
Cryoprotective and osmotic responses to cold acclimation and freezing in freeze-tolerant and freeze-intolerant earthworms 总被引:3,自引:3,他引:0
M. Holmstrup J. P. Costanzo R. E. Lee Jr 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》1999,169(3):207-214
In this paper we present the results of physiological responses to winter acclimation and tissue freezing in a freeze-tolerant
Siberian earthworm, Eisenia nordenskioeldi, and two freeze-intolerant, temperate earthworm species, Lumbricus rubellus and Aporrectodea caliginosa. By analysing the physiological responses to freezing of both types we sought to identify some key factors promoting freeze
tolerance in earthworms. Winter acclimation was followed by a significant increase in osmolality of body fluids in E. nordenskioeldi, from 197 mosmol kg−1 in 10 °C-acclimated animals to 365 mosmol kg−1 in animals acclimated to 0 °C. Cold acclimation did not cause any change in body fluid osmolality in the two freeze-intolerant
species. As a response to ice formation in the body, the freeze-intolerant species produced copious amounts of slime and expulsion
of coelomic fluids, and thereby lost 10–30% of their total water content. Contrary to this, the freeze-tolerant species did
not lose water upon freezing. At temperatures down to −6.5 °C, the ice content in the freeze-tolerant E. nordenskioeldi was significantly lower than in L. rubellus. At lower temperatures there were no differences in ice content between the two species. Cold acclimated, but unfrozen, specimens
of all three species had low levels of ammonia, urea, lactate, glycerol and glucose. As a response to ice formation, glucose
levels significantly increased within the first 24 h of freezing. This was most pronounced in E. nordenskioeldi where a 153-fold increase of glucose was seen (94 mmol · l−1). In L. rubellus and A. caliginosa a 19-fold and 17-fold increase in glucose was seen. This is the first study on physiological mechanisms promoting freeze
tolerance in E. nordenskioeldi, or any other oligochaete. Our results suggest that the cryoprotective system of this species more closely resembles that
of freeze-tolerant anurans, which synthesize cryoprotectants only after tissues begin to freeze, than that of cold-hardy invertebrates
which exhibit a preparatory accumulation of cryoprotectants during seasonal exposure to low temperature.
Accepted: 10 February 1999 相似文献
3.
4.
K. R. Jumbam J. S. Terblanche J. A. Deere M. J. Somers S. L. Chown 《Polar Biology》2008,31(2):215-220
Despite the relative richness of spider species across the Southern Ocean islands remarkably little information is available
on their biology. Here, the critical thermal limits of an indigenous (Myro kerguelenensis, Desidae) and an introduced (Prinerigone vagans, Linyphiidae) spider species from Marion Island were studied after 7–8 days acclimation to 0, 5, 10 and 15°C. Critical thermal
minima (CTMin) were low in these species by comparison with other spiders and insects measured to date, and ranged from −6 to −7°C in M. kerguelenensis and from −7 to −8°C in P. vagans. In contrast, critical thermal maxima (CTMax) were similar to other insects on Marion Island (M. kerguelenensis: 35.0–35.6°C; P. vagans: 35.1–36.0°C), although significantly lower than those reported for other spider species in the literature. The magnitude
of acclimation responses in CTMax was lower than those in CTMin for both species and this suggests decoupled responses to acclimation. Whilst not conclusive, the results raise several important
considerations: that oxygen limitation of thermal tolerance needs to be more widely investigated in terrestrial species, that
indigenous and alien species might differ in the nature and extent of their plasticity, and that upper and lower thermal tolerance
limits might be decoupled in spiders as is the case in insects. 相似文献
5.
Identification of quantitative trait loci and associated candidate genes for low-temperature tolerance in cold-hardy winter wheat 总被引:4,自引:0,他引:4
Båga M Chodaparambil SV Limin AE Pecar M Fowler DB Chibbar RN 《Functional & integrative genomics》2007,7(1):53-68
Low-temperature (LT) tolerance is an important economic trait in winter wheat (Triticum aestivum L.) that determines the plants’ ability to cope with below freezing temperatures. Essential elements of the LT tolerance mechanism are associated with the winter growth habit controlled by the vernalization loci (Vrn-1) on the group 5 chromosomes. To identify genomic regions, which in addition to vrn-1 determine the level of LT tolerance in hexaploid wheat, two doubled haploid (DH) mapping populations were produced using parents with winter growth habit (vrn-A1, vrn-B1, and vrn-D1) but showing different LT tolerance levels. A total of 107 DH lines were analyzed by genetic mapping to produce a consensus map of 2,873 cM. The LT tolerance levels for the Norstar (LT50=−20.7°C) × Winter Manitou (LT50=−14.3°C) mapping population ranged from −12.0 to −22.0°C. Single marker analysis and interval mapping of phenotyped lines revealed a major quantitative trait locus (QTL) on chromosome 5A and a weaker QTL on chromosome 1D. The 5A QTL located 46 cM proximal to the vrn-A1 locus explained 40% of the LT tolerance variance. Two C-repeat Binding Factor (CBF) genes expressed during cold acclimation in Norstar were located at the peak of the 5A QTL. 相似文献
6.
7.
Hydromedion sparsutum is a locally abundant herbivorous beetle on the sub-Antarctic island of South Georgia, often living in close association
with the tussock grass Parodiochloa flabellata. Over a 4-day period in mid-summer when the air temperature varied from 0 to 20°C, the temperature in the leaf litter 5–10 cm
deep at the base of tussock plants (the microhabitat of H. sparsutum) was consistently within the range of 5–7.5°C. Experiments were carried out to assess the ability of H. sparsutum larvae collected from this thermally stable environment to acclimate when maintained at lower (0°C) and higher (15°C) temperatures.
The mean supercooling points (freezing temperature) of larvae collected in January and acclimated at 0°C for 3 and 6 weeks
and 15°C for 3 weeks were all within the range of −2.6 to −4.6°C. Larvae in all treatment groups were freeze tolerant. Acclimation
at 0°C significantly increased survival in a 15-min exposure at −8°C (from 27 to 96%) and −10°C (from 0 to 63%) compared with
the field-fresh and 15°C-treated larvae. Similarly, survival of 0°C-acclimated larvae in a 72-h exposure at −6°C increased
from 20 to 83%. Extending the acclimation period at 0°C to 6 weeks did not produce any further increase in cold tolerance.
The concentrations of glucose and trehalose in larval body fluids increased significantly with low temperature acclimation.
Larvae maintained at 15°C for 3 weeks (none survived for 6 weeks) were less able to survive 1-h exposures between 30 and 35°C
than the 0°C-treated samples. Whilst vegetation and snow cover are an effective buffer against low winter temperatures in
many polar insects, the inability of H. sparsutum larvae to acclimate or survive at 15°C suggests that protection against high summer temperatures is equally important for
this species.
Accepted: 2 August 1999 相似文献
8.
Wen-Jun Wang Fei-Jiu Wang Jian-Yi Zhu Xiu-Tao Sun Chun-Yan Yao Pu Xu 《Journal of applied phycology》2011,23(6):1017-1022
In January and February 2010, heavy sea ice formed along the coast of the Bohai Sea and the northern Yellow Sea, China. Intertidal
organisms were subjected to serious freezing stress. In this study, we investigated the freezing tolerance of the upper intertidal
economic seaweed Porphyra yezoensis. The maximum photochemical efficiency of PS II (F
v/F
m) in undehydrated thalli remained high after 24 h at −2°C and that in dehydrated thalli decreased in a proportion to thallial
water loss. F
v/F
m dropped sharply after 24 h at −20°C, regardless of absolute cellular water content (AWC). The F
v/F
m in frozen thalli recovered rapidly at 0–20°C. A wide range of water loss in the thalli enhanced their tolerance to freezing.
F
v/F
m values in undehydrated thalli dropped sharply after 3 d at −2°C or 10 d at −20°C while those in dehydrated thalli (20–53%
AWCs) remained at high levels after 9 d at −2°C or 30 d at −20°C. These results indicate that P. yezoensis has high freezing tolerance by means of dehydration during the ebb tide and rapid recovery of F
v/F
m from freezing. A strategy of P. yezoensis industry to avoid heavy loss during freezing season is discussed based on these findings. 相似文献
9.
Potato is a species commonly cultivated in temperate areas where the growing season may be interrupted by frosts, resulting in loss of yield. Cultivated potato, Solanum tuberosum, is freezing sensitive, but it has several freezing-tolerant wild potato relatives, one of which is S. commersonii. Our study was aimed to resolve the relationship between enhanced freezing tolerance, acclimation capacity and capacity to tolerate active oxygen species. To be able to characterize freezing tolerant ideotypes, a potato population (S1), which segregates in freezing tolerance, acclimation capacity and capacity to tolerate superoxide radicals, was produced by selfing a somatic hybrid between a freezing-tolerant Solanum commersonii (LT50=-4.6°C) and -sensitive S. tuberosum (LT50=-3.0°C). The distribution of non-acclimated freezing tolerance (NA-freezing tolerance) of the S1 population varied between the parental lines and we were able to identify genotypes, having significantly high or low NA-freezing tolerance. When a population of 25 genotypes was tested both for NA-freezing and paraquat (PQ) tolerance, no correlation was found between these two traits (R = 0.02). However, the most NA-freezing tolerant genotypes were also among the most PQ tolerant plants. Simultaneously, one of the NA-freezing sensitive genotypes (2022) (LT50=-3.0°C) was observed to be PQ tolerant. These conflicting results may reflect a significant, but not obligatory, role of superoxide scavenging mechanisms in the NA-freezing tolerance of S. commersonii. The freezing tolerance after cold acclimation (CA-freezing tolerance) and the acclimation capacity (AC) was measured after acclimation for 7 days at 4/2°C. Lack of correlation between NA-freezing tolerance and AC (R =-0.05) in the S1 population points to independent genetic control of NA-freezing tolerance and AC in Solanum sp. Increased freezing tolerance after cold acclimation was clearly related to PQ tolerance of all S1 genotypes, especially those having good acclimation capacity. The rapid loss of improved PQ tolerance under deacclimation conditions confirmed the close relationship between the process of cold acclimation and enhanced PQ tolerance. Here, we report an increased PQ tolerance in cold-acclimated plants compared to non-acclimated controls. However, we concluded that high PQ tolerance is not a good indicator of actual freezing tolerance and should not be used as a selectable marker for the identification of a freezing-tolerant genotype. 相似文献
10.
The freezing tolerance or cold acclimation of plants is enhanced over a period of time by temperatures below 10°C and by a
short photoperiod in certain species of trees and grasses. During this process, freezing tolerance increases 2–8°C in spring
annuals, 10–30°C in winter annuals, and 20–200°C in tree species. Gene upregulation and downregulation have been demonstrated
to be involved in response to environmental cues such as low temperature. Evidence suggests ABA can substitute for the low
temperature stimulus, provided there is also an adequate supply of sugars. Evidence also suggests there may be ABA-dependent
and ABA-independent pathways involved in the acclimation process. This review summarizes the role of ABA in cold acclimation
from both a historical and recent perspective. It is concluded that it is highly unlikely that ABA regulates all the genes
associated with cold acclimation; however, it definitely regulates many of the genes associated with an increase in freezing
tolerance. 相似文献
11.
Three species of Arctic to cold-temperate amphi-Atlantic algae, all occurring also in the North Pacific, were tested for growth
and/or survival at temperatures of −20 to 30°C. When isolates from both western and eastern Atlantic shores were tested side-by-side,
it was found that thermal ecotypes may occur in such Arctic algae.Chaetomorpha melagonium was the most eurythermal of the 3 species. Isolates of this alga were alike in temperature tolerance and growth rate but
Icelandic plants were more sensitive to the lethal temperature of 25°C than were more southerly isolates from both east and
west. With regard toDevaleraea ramentacea, one Canadian isolate grew extraordinarily well at −2 and 0°C, and all tolerated temperatures 2–3°C higher than the lethal
limit (18–20°C) of isolates from Europe. ConcerningPhycodrys rubens, both eastern and western isolates died at 20°C but European plants tolerated the lethal high temperature longer, were more
sensitive to freezing, and attained more rapid growth at optimal temperatures. The intertidal species,C. melagonium andD. ramentacea, both survived freezing at −5 and −20°C, at least for short time periods.C. melagonium was more susceptible thanD. ramentacea to desiccation. Patterns of thermal tolerance may provide insight into the evolutionary history of seaweed species. 相似文献
12.
Josef Elster Peter Degma Ľubomír Kováčik Lucia Valentová Katarína Šramková Antonio Batista Pereira 《Biologia》2008,63(6):843-851
The freezing and desiccation tolerance of 12 Klebsormidium strains, isolated from various habitats (aeroterrestrial, terrestrial, and hydro-terrestrial) from distinct geographical
regions (Antarctic — South Shetlands, King George Island, Arctic — Ellesmere Island, Svalbard, Central Europe — Slovakia)
were studied. Each strain was exposed to several freezing (−4°C, −40°C, −196°C) and desiccation (+4°C and + 20°C) regimes,
simulating both natural and semi-natural freeze-thaw and desiccation cycles. The level of resistance (or the survival capacity)
was evaluated by chlorophyll a content, viability, and chlorophyll fluorescence evaluations. No statistical differences (Kruskal-Wallis tests) between strains
originating from different regions were observed. All strains tested were highly resistant to both freezing and desiccation
injuries. Freezing down to −196°C was the most harmful regime for all studied strains. Freezing at −4°C did not influence
the survival of studied strains. Further, freezing down to −40°C (at a speed of 4°C/min) was not fatal for most of the strains.
RDA analysis showed that certain Antarctic and Arctic strains did not survive desiccation at +4°C; however, freezing at −40°C,
as well as desiccation at +20°C was not fatal to them. On the other hand, other strains from the Antarctic, the Arctic, and
Central Europe (Slovakia) survived desiccation at temperatures of +4°C, and freezing down to −40°C. It appears that species
of Klebsormidium which occupy an environment where both seasonal and diurnal variations of water availability prevail, are well adapted to
freezing and desiccation injuries. Freezing and desiccation tolerance is not species-specific nor is the resilience only found
in polar strains as it is also a feature of temperate strains.
Presented at the International Symposium Biology and Taxonomy of Green Algae V, Smolenice, June 26–29, 2007, Slovakia.
This paper is dedicated to the memory of the late Dr. Bohuslav Fott (1908–1976), Professor of Botany at the Charles University
in Prague, to mark the centenary of his birth. 相似文献
13.
Rhodamine-phalloidin staining of winter oilseed rape suspension cells revealed that the structure of actin cytoskeleton changes
with the phase of cell growth. In small, 4-day-old cells, entering the exponential phase of growth, a dense and uniformly
distributed cortical microfilament networks was seen. In six-day-old vacuolated cells, which reached the stationary phase
of growth, the actin cytoskeleton was composed of thicker microfilament cables in irregular arrangements. In cells acclimated
in cold for 7 days a dense, uniformly distributed and cortical microfilament network was still seen. The fine microfilament
network was sensitive to extracellular freezing since the structures underwent depolymerization at −3 °C (in the presence
of extracellular ice), both in non-acclimated and cold-acclimated cells. The thicker transvacuolar cables in cells of the
stationary growth phase resisted freezing to −7 °C. Acclimation of suspensions at 2 °C resulted in slowing down growth of
cells and in the increased freezing tolerance of cells as indicated by a decrease of LT50 from −11 °C to −17.5o or to −25 °C when determined 7 or 20 days after the beginning of the cold treatment, respectively. Freezing tolerance of
non-acclimated cells decreased from −11 °C to −8 °C during subculture, showing a transient increase to −17 °C on the day 6.
Results indicate that the arrangement of actin microfilaments and their sensitivity to freezing-induced depolymerization depends
on the phase of cell growth rather than on cell acclimation status. Possible mechanisms involved in the freezing-induced depolymerization
of actin microfilaments are discussed.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
14.
Zhou Ben-Lin; Arakawa Keita; Fujikawa Seizo; Yoshida Shizuo 《Plant & cell physiology》1994,35(2):175-182
The objective of this study was to identify plasma membraneproteins that are specifically induced by cold acclimation inwheat (Triticum aestivum L.). Two cultivars with a marked differencein the genetic ability to cold-acclimate, namely, spring wheat(cv. Chinese Spring) and winter wheat (cv. Norstar), were usedas the experimental material. After four weeks of growth ina cold chamber, the freezing tolerance in the shoots of winterwheat increased to 18°C, whereas it increased onlyto 8°C in the shoots of spring wheat. In the caseof roots from both cultivars, freezing tolerance increased onlyslightly after the growth in the cold environment. Cold acclimationinduced remarkable changes in the electrophoretic patterns ofplasma membrane proteins which depended on both the cultivarand the tissue examined. Levels of polypeptides with molecularmasses from 22 to 31 kDa decreased in both the root and shootplasma membranes from both cultivars. Among these polypeptides,levels of those of 28 and 26 kDa decreased abruptly after oneweek of cold acclimation. By contrast, levels of polypeptidesof 89, 83, 52, 23, 18 and 17 kDa increased specifically in theshoots of winter wheat. The increases in the levels of the 23-,18- and 17-kDa polypeptides were proportional to the developmentof freezing tolerance. Freeze-fracture electron microscopy ofplasma membranes from shoot cells revealed that the number ofintramembrane particles on the fracture faces decreased markedlyin winter wheat after cold acclimation, but to a lesser extentin spring wheat. These results suggest that the plasma membranesmight undergo molecular reorganization during cold acclimation.
1Contribution no. 3709 from the Institute of Low TemperatureScience, Hokkaido University. 相似文献
15.
The ability to survive freezing and thawing is a key factor for the existence of life forms in large parts of the world. However,
little is known about the freezing tolerance of mycorrhizal fungi and their role in the freezing tolerance of mycorrhizas.
Threshold temperatures for the survival of these fungi have not been assessed experimentally. We grew isolates of Suillus luteus, Suillus variegatus, Laccaria laccata, and Hebeloma sp. in liquid culture at room temperature. Subsequently, we exposed samples to a series of temperatures between +5°C and
−48°C. Relative electrolyte leakage (REL) and re-growth measurements were used to assess the damage. The REL test indicated
that the lethal temperature for 50% of samples (LT50) was between −8.3°C and −13.5°C. However, in the re-growth experiment, all isolates resumed growth after exposure to −8°C
and higher temperatures. As many as 64% of L. laccata samples but only 11% in S. variegatus survived −48°C. There was no growth of Hebeloma and S. luteus after exposure to −48°C, but part of their samples survived −30°C. The fungi tolerated lower temperatures than was expected
on the basis of earlier studies on fine roots of ectomycorrhizal trees. The most likely freezing tolerance mechanism here
is tolerance to apoplastic freezing and the concomitant intracellular dehydration with consequent concentrating of cryoprotectant
substances in cells. Studying the properties of fungi in isolation promotes the understanding of the role of the different
partners of the mycorrhizal symbiosis in the freezing tolerance. 相似文献
16.
17.
G. N. J. le Patourel 《Entomologia Experimentalis et Applicata》1993,68(3):257-263
The cold-hardiness of nymphal stages 1 to 5 and adult male and femaleBlatta orientalis was tested at 2°, −5° and −10°C. The LT50 (time) of insects exposed to −5° ranged from 0.21 to 0.43 days. Acclimation at
10° C for times varying up to 14 days progressively increased cold-hardiness. A 14 day acclimation at 10° prior to exposure
at −5°C increased LT50 (time) to 1.1–4.2 days for the various stages; prolonging the acclimation time to 28 days produced
no further increase in LT50. All stages were rapidly killed at −10°C (LT50<0.04 days) and survived prolonged exposures at
2°C (LT50s from 16 to >42 days) following acclimation. The potential for survival of outdoor populations ofB. orientalis over winter is discussed. 相似文献
18.
Significant increases in heat tolerance (time of survival at 14°C) were observed for some, but not all, species of notothenioid fishes collected from McMurdo Sound, Antarctica (77°51′S) following acclimation to 4°C. The increase in thermal tolerance was rapid in Trematomus bernacchii, developing within 1–2 days of acclimation to 4°C. Long-term (6–8 weeks) acclimation to 4°C led to greater heat tolerance in Trematomus pennellii than in T. bernacchii. Unlike its demersal congeners, the cryopelagic notothenioid Pagothenia borchgrevinki did not increase heat tolerance during warm acclimation. A deep-living zoarcid fish, Lycodichthys dearborni, also failed to increase heat tolerance, but survived significantly (> threefold) longer at 14°C than the notothenioids. 相似文献
19.
Antarctic wetlands are characterized by the presence of liquid water during short austral summer. Filamentous cyanobacteria are often dominant there and are exposed to severe conditions, of which the changes in the desiccation–rehydration and freeze–thaw cycles are two of the most stressful. Vigor, after freezing and desiccation, was laboratory tested in cyanobacterial and algal strains from wetland habitats collected in maritime and continental Antarctica. Whereas minor sub-zero temperatures (−4°C), demonstrating summer diurnal freeze–thaws did not cause significant damage on either cyanobacteria or algae, low sub-zero temperatures (−40, −100, −196°C), demonstrating annual winter freeze, caused little harm to cyanobacteria, but was fatal for more than 50% of the population of algae. Freezing and desiccation tolerance of these strains was compared using multiregression methods: cyanobacteria from continental Antarctica were significantly more tolerant to low sub-zero temperatures than similar strains from maritime Antarctica (P = 0.026; F = 3.66); and cyanobacteria from seepages habitat were less tolerant to freezing and desiccation than cyanobacteria from other wetlands (P = 0.002; F = 5.69). 相似文献
20.
Adaptation and acclimation of growth and photosynthesis of five Antarctic red algae to low temperatures 总被引:2,自引:0,他引:2
Temperature requirements for growth, photosynthesis and dark respiration were determined for five Antarctic red algal species.
After acclimation, the stenothermal species Gigartina skottsbergii and Ballia callitricha grew at 0 or up to 5 °C, respectively; the eurythermal species Kallymenia antarctica, Gymnogongrus antarcticus and Phyllophora ahnfeltioides grew up to 10 °C. The temperature optima of photosynthesis were between 10 and 15 °C in the stenothermal species and between
15 and 25 °C in the eurythermal species, irrespective of the growth temperature. This shows that the temperature optima for
photosynthesis are located well below the optima from species of other biogeographical regions, even from the Arctic. Respiratory
rates rose with increasing temperatures. In contrast to photosynthesis, no temperature optimum was evident between 0 and 25 °C.
Partial acclimation of photosynthetic capacity to growth temperature was found in two species. B. callitricha and Gymnogongrus antarcticus acclimate to 0 °C, and 5 and 0 °C, respectively. But acclimation did in no case lead to an overall shift in the temperature
optimum of photosynthesis. B. callitricha and Gymnogongrus antarcticus showed acclimation of respiration to 5 °C, and P. ahnfeltioides to 5 and 10 °C, resulting in a temperature independence of respiration when measured at growth temperature. With respect
to the acclimation potential of the species, no distinction can be made between the stenothermal versus the eurythermal group.
(Net)photosynthetic capacity:respiration (P:R) ratios showed in all species highest values at 0 °C and decreased continuously to values lower than 1.0 at 25 °C. In turn,
the low P:R ratios at higher temperatures are assumed to determine the upper temperature growth limit of the studied species. Estimated
daily carbon balance reached values between 4.1 and 30.7 mg C g−1 FW day−1 at 0 °C, 16:8 h light/dark cycle, 12–40 μmol m−2 s−1.
Received: 4 November 1999 / Accepted: 7 March 2000 相似文献