首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
2.
The terrestrial environment is complex, with many parameters fluctuating on daily and seasonal basis. Plants, in particular, have developed complex sensory and signaling networks to extract and integrate information about their surroundings in order to maximize their fitness and mitigate some of the detrimental effects of their sessile lifestyles. Light and temperature each provide crucial insights on the surrounding environment and, in combination, allow plants to appropriately develop, grow and adapt. Cross-talk between light and temperature signaling cascades allows plants to time key developmental decisions to ensure they are ‘in sync’ with their environment. In this review, we discuss the major players that regulate light and temperature signaling, and the cross-talk between them, in reference to a crucial developmental decision faced by plants: to bloom or not to bloom?  相似文献   

3.
[目的]本研究旨在探明短额负蝗Atractomorpha sinensis不同地理种群对环境温度响应的适应性差异.[方法]以大豆叶片为食物饲养,在恒温16,20,24,28和32℃,相对湿度70%,光周期16L:8D条件下,系统观测陕西延安、河南郑州、四川成都、云南曲靖和广东广州5个短额负蝗地理种群的生长发育过程,比较...  相似文献   

4.
桃小食心虫的发育起点温度和有效积温   总被引:2,自引:0,他引:2  
在17~29℃、RH80%±7%和光周期L:D=15:9的条件下,测定了桃小食心虫Carposina sasakii Matsumura各虫态的发育历期,计算了桃小食心虫卵、幼虫、蛹和全世代的发育起点温度和有效积温。结果表明,各虫态的发育历期随着温度的升高而缩短,各虫态的发育速率与温度之间具有良好的线性关系。桃小食心虫卵、幼虫、结茧前期、蛹及生殖前期的发育起点温度分别为10.02、9.44、10.58、10.09和9.51℃,有效积温分别为87.3、238.6、10.7、156.9和31.6日·度,全世代的发育起点温度和有效积温分别为9.22℃和543.2日·度。  相似文献   

5.
In many oviparous vertebrates, hatchling phenotypes are influenced by egg incubation temperature. Many of those phenotypic traits can also acclimate to long-term thermal conditions of juveniles and adults, yet the interactive effects of prehatching and posthatching temperatures on phenotypes have not been studied. To address such interaction, we incubated eggs of wood frogs (Rana sylvatica) at two temperatures and subsequently reared larvae at three temperatures in a fully factorial design. We measured body size, size-independent morphology, and burst swimming speed at one developmental stage. Body size was independent of egg temperature but decreased significantly with increasing larval temperature. Size-independent morphology depended in complex ways on both temperature treatments directly and on their interaction. Burst speed was not influenced directly by egg temperature but was influenced by larval temperature and by the interactions among egg temperature, larval temperature, and test temperature. Our results indicate pervasive effects of egg temperature even late in the larval period and show that prehatching and posthatching temperatures can interact to affect various phenotypic traits. Tadpoles may be able to alter the long-term effects of incubation temperature by choosing particular larval developmental temperatures. Thus, the importance of incubation temperature in oviparous vertebrates should be evaluated by considering the effects of posthatching temperatures.  相似文献   

6.
We use a full factorial design to investigate the effects of maternal and paternal developmental temperature, as well as female oviposition temperature, on egg size in the butterfly Bicyclus anynana. Butterflies were raised at two different temperatures and mated in four possible sex-by-parental-temperature crosses. The mated females were randomly divided between high and low oviposition temperatures. On the first day after assigning the females to different temperatures, only female developmental temperature affected egg size. Females reared at the lower temperature laid larger eggs than those reared at a higher temperature. When eggs were measured again after an acclimation period of 10 days, egg size was principally determined by the prevailing temperature during oviposition, with females ovipositing at a lower temperature laying larger eggs. In contrast to widely used assumptions, the effects of developmental temperature were largely reversible. Male developmental temperature did not affect egg size in either of the measurements. Overall, developmental plasticity and acclimation in the adult stage resulted in very similar patterns of egg size plasticity. Consequently, we argue that the most important question when testing the significance of acclamatory changes is not at which stage a given plasticity is induced, but rather whether plastic responses to environmental change are adaptive or merely physiological constraints.  相似文献   

7.
利用光照培养箱,在16、19、22、25、28、31和34℃7个恒温条件下饲养金银花尺蠖Heterolocha jinyinhuaphaga Chu,对其各虫态的发育历期、发育起点温度和有效积温进行了研究。结果表明,该虫在16~34℃的温度范围内均能正常生长发育,但各虫态的发育历期随温度变化而变化,在31℃以下的温度时,发育历期随温度的升高而缩短,超过31℃时,发育速度反而减慢,发育历期则逐渐延长;卵、幼虫、蛹、产卵前期和整个世代的发育起点温度分别为9.42、11.44、5.42、13.98和9.74℃,有效积温分别为122.64、303.15、195.95、39.15和673.03日.度;根据有效积温法则预测该虫在滁州市1年的理论发生代数为3.07代,这与实际发生情况基本相符合。  相似文献   

8.
In crocodilians, the rate of embryonic development and consequently many posthatch attributes are affected by temperature. Since temperature exhibits strong influences on fitness (embryo survivorship and phenotype) by shaping development, we manipulated oxygen concentration in order to uncouple the effects of developmental rate from the direct effects of temperature. Here we consider whether oxygen constrains either differentiation rate (progression from one stage to the next) or embryonic growth (size). Thus, we incubated Caiman latirostris eggs at various oxygen concentrations, and at two temperatures (31 °C, 100% female-producing temperature, and 33 °C, 100% male-producing temperature). We monitored the developmental stages of these embryos within the thermosensitive period (stages 20–24), and assessed several physiological and morphological hatchling traits. While embryonic size was strongly influenced by oxygen, differentiation rate did not seem to be affected. Very low oxygen concentrations and high temperatures inhibited embryo survival. In addition, oxygen availability affected incubation period and hatchling size, whereas temperature did not cause a significant variation in hatchling size. By investing energy in differentiation hypoxic embryos decreased their size.  相似文献   

9.
核桃扁叶甲的发育起点温度和有效积温   总被引:1,自引:0,他引:1  
室内观察测定5个恒温条件下,核桃扁叶甲Gastrolina depressa Baly各虫态的发育历期及起点温度和有效积温。结果表明:在16~32℃温度范围内,核桃扁叶甲均能完成发育,其发育历期随温度的升高而缩短,卵期、幼虫期、蛹期、产卵前期的发育起点温度分别为9.4,12.2,14.3和11.1℃,有效积温分别为43.2,77.2,36.0和104.7日.度;整个世代的发育起点温度为12.0℃,有效积温为260.5日.度。持续过高温度不适合核桃扁叶甲的生长发育。  相似文献   

10.
Previous work has suggested that developmental temperature influences expression of the adult male calling song of the cricket, a sexually selected mate recognition signal. The role of developmental temperature in shaping female preference functions, and thus its influence on signal-preference coupling has not been investigated. In this study, the effects of developmental temperature are examined in both males and females of the Hawaiian cricket, Laupala cerasina, to determine the degree of signal-preference matching between male song and female preference due to developmental environment. We found that rearing females in different temperature environments affected adult female acoustic preference functions in the same direction as male calling song, thereby influencing variation in adult reproductive behavior in such a way that male and female components remain coordinated. However, we further demonstrate that for male song, the effect of the rearing environment is not permanent but appears only to exert influence for a period of days. This mid-term temperature effect is distinct from the effect of short-term ambient temperature, which influences song in a matter of minutes and has been well documented. Signal-preference coordination, and sexual selection pressures due to mismatching within natural populations, likely will be influenced by nymphal developmental environments of males and females, as well as by adult singing and preference environments.  相似文献   

11.
家蝇发育起点温度和有效积温   总被引:4,自引:0,他引:4  
范丽清  罗广军 《昆虫知识》2006,43(3):429-430
在5种温度下,对家蝇的发育起点温度和有效积温进行了研究。结果表明,家蝇在不同发育阶段发育起点温度和有效积温不同,且不同发育阶段对两者的要求也不一致。世代的发育起点温度和有效积温分别为13.6℃和196.4日.度,控制发育进度的理论为T=196.4/N+(13.6±0.5)。  相似文献   

12.
The developmental rate under low temperatures and cold tolerance were investigated in embryos of the blowfly Lucilia sericata. The larvae of this species are now widely used in maggot debridement therapy. Embryonic development was dependent on temperature, with a lower developmental threshold of 9.0 °C. The duration of the egg stage at a rearing temperature of 25 °C was 14 h, and a low temperature of 12.5 °C successfully prolonged this period to 66 h. Embryonic stages differed markedly in their cold tolerance; young embryos were less tolerant to cold than old ones. Late embryonic stages are suitable for cold storage at 5 °C and the storage for 72 h did not decrease the hatching rate by more than 50%. In the mass‐rearing process required for maggot debridement therapy, either of these two simple protocols would be beneficial.  相似文献   

13.
Ectotherms are sensitive to changes in ambient temperature that impact their physiology and development. To compensate for the effects of variation in temperature, ectotherms exhibit short or long-term physiological plasticity. An extensive body of literature exists towards understanding these effects and the solutions ectotherms have evolved. However, to what extent rearing temperature during early life stages impacts the behaviour expressed in adulthood is less clearly understood. In the present study, we aimed to examine the effects of developmental temperature on life-history traits and mating call features in a tropical field cricket, Acanthogryllus asiaticus. We raised A. asiaticus at two different developmental conditions: 25 °C and 30 °C. We found developmental time and adult lifespan of individuals reared at 30 °C to be shorter than those reared at 25 °C. Increased developmental temperature influenced various body size parameters differentially. Males raised at 30 °C were found to be larger and heavier than those raised at 25 °C, making A. asiaticus an exception to the temperature-size rule. We found a significant effect of change in immediate ambient temperature on different call features of both field-caught and lab-bred individuals. Developmental temperature also affected mating call features wherein individuals raised at higher temperature produced faster calls with a higher peak frequency compared to those raised at lower temperature. In addition, an interactive effect of both developmental and immediate temperature was found on mating call features. Our study highlights the importance of understanding how environmental temperature shapes life-history and sexual communication in crickets.  相似文献   

14.
In order to study how polyploidy affects life history patterns in animals, we have examined sympatric diploid and polyploid brine shrimp (Artemia parthenogenetica) from China, Italy and Spain under laboratory conditions. At optimal temperature and salinity (25°C and 90 ppt), diploids from the three populations had much higher intrinsic rates of increase, higher fecundity, faster developmental rates, and larger brood sizes than their sympatric polyploids. The Chinese and Italian populations were selected for further analysis to determine the life history responses of diploids and polyploids to temperature and salinity changes. Under intermediate and high salinities, Chinese and Italian polyploids produced most of their offspring as dormant cysts while their sympatric diploids produced most of their offspring as nauplii. This relationship is reversed in the Spanish diploid-polyploid complex. For the Chinese population at 25° C, pentaploid clones had higher developmental rates than diploid clones at 35 ppt; at 90 ppt, diploid clones had higher developmental rates than the pentaploids. Italian diploids and tetraploids had different responses to variation in both temperature (25° C and 31° C) and salinity (30 ppt and 180 ppt). Our results demonstrate that relative fitness of the two cytotypes is a function of environmental conditions and that sympatric diploids and polyploids respond differently to environmental changes. Chinese and Italian polyploids are expected to have lower fitness than their sympatric diploids when the physical environment is not stressful and when intraspecific competition is important. However, polyploids may have advantages over sympatric diploids in stressful habitats or when they encounter short-term lethal temperatures. These results suggest that polyploid Artemia have evolved a suite of life-history characteristics adapting them to environments that contrast to those of their sympatric diploids.  相似文献   

15.
16.
We explored the adaptive significance of developmental plasticity in the tropical butterfly Bicyclus anynana using two experiments including temperature changes during ontogeny. In contrast to previous findings on adult acclimation, we could not find any evidence in support of adaptive developmental plasticity, as survival until adulthood was not enhanced when larval rearing temperatures matched the temperatures experienced during prepupal or pupal development. Extreme temperatures substantially reduced survival, supporting the ‘optimal developmental temperature’ hypothesis. Metamorphosis was more efficient at the higher rearing temperature of 27 °C, where egg hatching success was also higher, indicating that the lower temperature of 20 °C is already slightly stressful for this tropical butterfly.  相似文献   

17.
At refrigeration temperature, mouse embryos can retain their developmental ability for a couple of days. Previous research reports have focused on the effect of cool temperature on the development of 2-cell stage embryos, morulae or blastocysts and determined that the embryo still has the ability to produce offspring after about 48 h storage at refrigeration temperature. Here we examined whether refrigeration temperature affects the development of the eight-cell stage and if the stored eight-cell stage embryo can still be used as a host embryo for ES cell injection. Our results show that eight-cell stage embryos can develop into blastocysts and yield pups after cold storage for 24 and 48 h. After ES cell injection, stored eight-cell stage embryos can support ES cells developing to F0 pups. In summary, cool storage can preserve the developmental ability of eight-cell stage embryos for at least 48 h, allowing transportation of the embryos at refrigeration temperature between different labs and their subsequent use as host embryos for ES cell injection.  相似文献   

18.
Tolerance of ectotherm species to cold stress is highly plastic according to thermal conditions experienced prior to cold stress. In this study, we investigated how cold tolerance varies with developmental temperature (at 17, 25 and 30 °C) and whether developmental temperature induces different metabolic profiles. Experiments were conducted on the two populations of the parasitoid wasp, Venturia canescens, undergoing contrasting thermal regimes in their respective preferential habitat (thermally variable vs. buffered). We predicted the following: i) development at low temperatures improves the cold tolerance of parasitoid wasps, ii) the shape of the cold tolerance reaction norm differs between the two populations, and iii) these phenotypic variations are correlated with their metabolic profiles. Our results showed that habitat origin and developmental acclimation interact to determine cold tolerance and metabolic profiles of the parasitoid wasps. Cold tolerance was promoted when developmental temperatures declined and population originating from variable habitat presented a higher cold tolerance. Cold tolerance increases through the accumulation of metabolites with an assumed cryoprotective function and the depression of metabolites involved in energy metabolism. Our data provide an original example of how intraspecific cold acclimation variations correlate with metabolic response to developmental temperature.  相似文献   

19.
The development of the triactinomyxon stage of Myxobolus cerebralis and release of mature spores from Tubifex tubifex were shown to be temperature dependent. In the present work, the effect of temperature over a range of 5-30 degrees C on the development and release of the triactinomyxon stages of M. cerebralis was studied. Infected T. tubifex stopped releasing triactinomyxon spores 4 days after transfer from 15 degrees C to 25 degrees C or 30 degrees C. Transmission electron microscopic examinations of the tubificids held at 25 degrees C and 30 degrees C for 3 days showed that all developmental stages degenerated and transformed to electron-dense clusters between the gut epithelial cells of T. tubifex. In contrast, tubificid worms held at 5 degrees C and 10 degrees C examined at the same time were heavily infected with many early developmental stages of triactinomyxon. At 15 degrees C, the optimal temperature for development, maturing and mature stages of the parasite were evident. Infected T. tubifex transferred from 15 degrees C to 20 degrees C stopped producing triactinomyxon spores after 15 days. However, 15 days at 20 degrees C was not sufficient to destroy all developmental stages of the parasite. When the tubificid worms were returned to 15 degrees C, the one-cell stages and the binucleate-cell stages resumed normal growth. It was also demonstrated that T. tubifex cured of infection by holding at 30 degrees C for 3 weeks and shifted to 15 degrees C could be re-infected with M. cerebralis spores. The waterborne triactinomyxon spores of M. cerebralis did not appear to be as short-lived as previously reported. More than 60% of experimentally produced waterborne triactinomyxon spores survived and maintained their infectivity for rainbow trout for 15 days at water temperatures up to 15 degrees C. In natural aquatic systems, the triactinomyxon spores may survive and keep their infectivity for periods even longer than 15 days.  相似文献   

20.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号