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.
Laboratory avoidance tests were conducted to assess the behavioural reactions of five common collembolan species (Isotoma anglicana, Heteromurus nitidus, Lepidocyrtus violaceus, Folsomia candida, Onychiurus armatus) towards the herbicide Betanal (active ingredient: phenmedipham) in soil. Betanal exerted a dose-dependent repellent action on all tested species. In the case of O. armatus, the sensitivity of the avoidance test exceeded that of mortality and reproduction tests. It is concluded that, in addition to ecotoxicological tests on mortality and reproduction, a test system for assessing behavioural responses could provide more detailed information on the impact of pesticides and other harmful substances on Collembola.  相似文献   

2.
Several studies reported variable effects of earthworms on microarthropod density and variety. The present study tests the attraction of seven collembolan species belonging to four families, to the excreta of two earthworm species belonging to two families and two ecological categories, Aporrectodea giardi and Hormogaster elisae. Our objectives were (1) to better understand the impact of earthworms on the composition and density of Collembola communities, and (2) to dissect mechanisms involved in the attraction. Experiments were performed in Petri dishes containing two half-disks of filter paper, one with earthworm excreta, i.e. casts or a mix of mucus and urine, and the other with natural soil aggregates or water, respectively. Collembola were introduced half-way between the two half-disks and their number was counted on each half-disk and compared over 140 min. The content of ammonium in casts and mucus-urine of both earthworm species was analyzed to determine whether it altered the responses of Collembola faced with different types of earthworm excreta. The behaviour of Collembola varied strongly among the seven collembolan species, and with type of excreta and earthworm species. Six collembolan species were attracted to the mucus and urine of at least one earthworm species. The mucus-urine mixture of A. giardi, with low ammonium content, was generally more attractive than that of H. elisae, which was even repulsive in some cases, probably because of high levels of ammonium. The attraction to casts of the two earthworm species was less frequent and more variable. Folsomia candida was neither attracted to the casts nor to the mucus and urine of any earthworm species. Therefore, (1) earthworm species with different ecology, and different nitrogen excretion pathway impact differently the behaviour of collembolan species belonging to the same family or arising from the same habitat, and (2) variations in the sensitivity to ammonium among collembolan species partially explain the variable response of Collembola to earthworm excreta.  相似文献   

3.
An approach for testing acute and chronic ecotoxicological effects of pesticides on isopods in the laboratory is presented. Laboratory cultures of tropical Porcellionides pruinosus were used. The pesticides Benomyl, Carbendazim and lambda-Cyhalothrin served as model chemicals. The toxicity tests were done with five to six concentrations and one untreated control in four replicates containing 10 individuals per vessel. The test was performed at 28 °C, in permanent darkness and it lasted 14 days. Each chemical was mixed in 250 g DW per vessel of OECD artificial, LUFA 2.2 standard, tropical artificial or tropical natural soil in acute tests. Chronic tests were performed using 150 g DW OECD artificial or LUFA 2.2 standard soil. Both adult mortality and number of juveniles showed a high sensitivity of P. pruinosus towards lambda-Cyhalothrin while Carbendazim and Benomyl had a very low and no toxicity, respectively. Further research and optimization of the chronic test design are required.  相似文献   

4.
《Applied soil ecology》2000,14(2):103-110
Ecotoxicological tests are increasingly being used to evaluate the toxicity of a substance or mixture of substances towards soil fauna. One of these uses the parthenogenetic collembolan Folsomia candida to test for soil contamination, and this has been standardised in Europe. However, in such studies, it is important to know whether different laboratories use genetically close clones.In this study, nine clones of the parthenogenetic collembolan F. candida, used in five laboratories, have been subtyped by amplification of random regions of genomic DNA using 10-base primers in the random-amplified polymorphic DNA polymerase chain reaction (RAPD-PCR). This differentiated these clones into three groups of four, four and one, respectively. Several hypotheses can be envisaged to explain these divergences between the populations of this parthenogenetic collembolan, notably the history of interlaboratory exchanges of clones. Ecotoxicological tests (mortality and reproduction) were undertaken to test the sensitivities to cadmium and phenantrene of two clones from different RAPD defined groups. These showed minor differences in sensitivities to both, but more extensive testing with five cadmium concentrations showed that the genetic clone does not affect the LOEC determination. There is no evidence of significant differences between clones throughout a concentration gradient of cadmium.  相似文献   

5.
Background, Aims, and Scope  The springtail Folsomia candida is a commonly used model species in ecotoxicological soil testing. The species reproduces parthenogenetically and, thus, laboratories use different clonal lineages. In this study, we investigated if genetic divergence between F. candida strains impacts the reaction to chemical stress and may thus affect the outcome of toxicity tests. Methods  In two exposure assays (life-cycle reproduction test and avoidance behaviour test), three laboratory strains of F. candida from Portugal (PTG), Spain (SPN) and Denmark (DNK) were exposed to different concentrations of the reference chemical phenmedipham. Genetic divergence among strains was estimated based on mitochondrial COI sequence data. Results  No significant differences between tolerance towards phenmedipham exposure were observed in a reproduction test. In contrast, one strain (SPN) showed a decreased susceptibility to phenmedipham compared to the other strains (PTG and DNK) in the avoidance assay. Discussion  A phylogenetic tree based on mitochondrial COI sequences revealed clear genetic differentiation between both ‘reaction types’. Thus, we found a potential lineage dependent stress reaction in avoidance behaviour towards the pesticide. Conclusions  Our findings have implications for the comparability of test results among laboratories. Reproduction tests seem to be more robust towards interclonal genetic differentiation than avoidance tests. Recommendations and Perspectives  We recommend the use of molecular tools for simple and cost effective genetic characterization of F. candida strains used in chemical avoidance tests. Closer investigations concerning the relation between genetic relatedness and chemical response will provide a more detailed and comprehensive picture on the role of intraspecific genetic differentiation in stress tolerance. ESS-Submission Editor: Prof. Dr. Henner Hollert (henner.hollert@bio5.rwth-aachen.de)  相似文献   

6.
We examined whether co-existing Hypogastrura species feeding on fruit-bodies show differences in utilization of fruit-bodies, and whether their utilization reflect their preferences for basidiomycete species, by field surveys and bait-trap experiments. In field surveys, the relative densities of the collembolans, Hypogastrura denisana, H. denticulata, and Hypogastrura sp. 1, on the selected basidiomycete species, Cortinarius salor, Lactarius quietus, and Russula emetica, differed significantly between the collembolan species. In bait-trap experiments using fruit-bodies of the three basidiomycete species as bait, the relative densities of the three collembolan species on the basidiomycete species differed significantly between the collembolan species and these differences were similar to the differences observed in the field surveys. These results suggest that the three collembolan species have differential preferences for fruit-bodies of the three selected basidiomycete species, and that the preferences relate to their utilization of fruit-bodies.  相似文献   

7.
《Applied soil ecology》2007,35(3):461-472
The reproduction test with the collembolan Folsomia candida is used as a tool to evaluate the ecotoxicological potential of organic wastes currently applied to soil. Seven organic wastes (dewatered sewage sludges, thermally dried sewage sludges, composted sewage sludges, and a thermally dried pig slurry) were tested. These wastes had different origins, treatments, and pollutant burdens, and were selected as a representative sample of the wide variety of wastes currently generated. F. candida showed varied sensitivity depending on the waste, but also depending on the endpoint assessed. Reproduction was more sensitive than survival, although no correlations between reproduction and physico-chemical parameters and pollutant burden could be found. On the other hand, mortality was directly related to the lack of stability of wastes, probably reflecting the toxicity of end-products such as ammonium. Body length was not shown to be a sensitive endpoint for waste testing, as it was neither affected nor even stimulated by waste concentrations.Organic matter, pH, and electrical conductivity varied with waste concentration in soil-waste mixtures, although their effect on collembolan performance was expected to be low and part of the complex effect exerted by wastes when applied to real soils. Selection of the water content is the most problematic aspect in waste testing, as it may affect the performance of test organisms. In this study, a qualitative approach for water content selection in waste testing was considered to be the most suitable.Treatment of wastes affected composition and toxicity. Composting of sewage sludge increased its stability, compared to the initial sludge, but decreased its non-persistent organic pollutant burden and toxicity. On the other hand, thermally dried wastes from sludge and pig slurry displayed high toxicity, mainly attributable to their low stability. The results from the study indicate the inability of chemical methods to predict the effects of complex mixtures on living organisms with respect to ecotoxicity bioassays, but also the need for stabilization treatments of organic wastes prior to their reuse in soils.  相似文献   

8.
Fungi represent a major part of the living biomass in the upper soil horizon and serve as an important food source for many soil organisms. We hypothesized that certain mycelial characteristics may serve to protect fungi from grazing. Specifically, this study focused on the influence of poisonous or other repellent metabolites and crystalline structures at the hyphal surface on the feeding preference of the soil microarthropod Folsomia candida Willem. The formation of crystalline structures was studied microscopically and the content of certain metabolites such as amanitin and muscarin was investigated using analytical methods. The feeding preference of F. candida was studied in different in-vitro food choice experiments. Additionally, the palatability of the fungal isolates was estimated by the amount of egg clusters laid by F. candida and by analysing the carbon and nitrogen content of the mycelia. F. candida was repelled by fungal species with toxic metabolites or crystals on their hyphal surface, which indicates that these traits serve as feeding protection. F. candida preferred dark-pigmented fungi. Total number of egg clusters and feeding preference were not correlated. However, insects that fed on fungi without repellent characteristics laid the most eggs. The amount of carbon and nitrogen in the mycelium had no influence on feeding behaviour. We conclude that the content of repellent metabolites and crystalline structures at the hyphal surface are defensive strategies of soil fungi and strongly influence feeding preference of F. candida. Other traits such as palatability were less important. Our results help to explain collembolan feeding behaviour and interactions between soil fungi and Collembola.  相似文献   

9.
Folsomia candida (order Collembola), a common soil arthropod, has recently been described living in a shallow (2.5–5.7 m below surface), unconsolidated aquifer in southwestern Michigan. F. candida was haplotyped from 14 wells using inter-simple sequence repeats (ISSRs) markers, and genetic variation in F. candida was used as a bioindicator to identify pore scale to mesoscale migration barriers in the aquifer. With one exception, individual haplotypes were only found in single wells. A significant relationship was identified between interpopulation genetic differentiation and geographic distance, and F. candida exhibits genetic population structuring over a very fine geographic scale (0.65 km2). Monmonier's algorithm was used to identify two most likely subsurface barriers to migration. Hypothesized barriers divided the F. candida populations into three genetically distinct groups, with two groups separated by only 15 m. These groupings are not dependent on groundwater flow direction, and are supported by a minimum spanning network and AMOVA analysis. Because F. candida movement is limited by pore size, these barriers identify local areas of low permeability in the aquifer material. The study suggests that F. candida may serve an important role in identifying geological characteristics and patterns in aquifers that may be difficult to evaluate by other means.  相似文献   

10.
土壤中苯并[a]芘对白符跳(Folsomia candida)的生态毒性研究   总被引：1，自引：0，他引：1  
苯并(a)芘（B[a]P）是一种典型的多环芳烃（PAHs）,在油田周边和污灌区土壤中有较高的检出率。在污染土壤生态风险评估和制定土壤生态基准时,常用土壤跳虫作为敏感生态受体,但已有研究表明,目前常用的成虫生长率、死亡率和繁殖率等指标特征往往仅对土壤中高剂量B[a]P产生毒性响应。采用白符跳（Folsomia candida）的生态毒理试验筛选可用于较低剂量B[a]P下新的敏感指标特征,并比较其在两种典型地带性土壤天津潮土和鹰潭红壤之间的敏感性差异。结果表明,幼虫的生长指标最敏感,能对土壤较低浓度B[a]P产生毒性响应,可作为指示土壤B[a]P毒性的指标。四个指标的敏感度依次为：幼虫体长>成虫体长>繁殖数>存活数。B[a]P对白符跳的毒性效应在两种土壤类型间存在显著差异（红壤和潮土中幼虫体长的最低效应浓度（LOEC）值分别为1和500 mg kg-1）,可能受土壤理化性质,特别是有机质含量和pH的影响,在制定土壤生态基准时需对不同土壤的毒性数据进行归一化校正。  相似文献   

11.
Freely available glucose improves the conditions for soil microorganisms which are utilized as food by Collembola. We examined the effects of glucose application on collembolan (Folsomia candida Willem) growth and on several biotic and abiotic soil parameters (microbial biomass, soil respiration, qCO2, dissolved organic carbon, inorganic nitrogen, and Olson-P) in an artificial system without predatory pressure on Collembola. Glucose addition increased soil respiration and qCO2, and decreased nutrient levels in the soil. Collembolan growth increased with increasing glucose doses. We conclude that the availability of carbon substrates can sustain collembolan growth via an improvement of microbial growth conditions.  相似文献   

12.
 Soil microarthropods have been shown to stimulate or be detrimental to arbuscular mycorrhizal function by their grazing actions, but their role as dispersal agents has not been assessed. The ability of three species of arbuscular mycorrhizal (AM) fungi (Glomus etunicatum, Acaulospora denticulata, Scutellospora calospora) infecting Plantago lanceolata roots to further colonize neighbouring plants was measured in response to the distance between root systems and the presence of the collembolan, Folsomia candida. In the absence of collembola, all three fungal species infected neighbouring plants in two weeks or less (at short distances), but were not successful when neighbouring plants were placed 45 cm away or further. Colonization by G. etunicatum was the quickest at short distances, but S. calospora showed greatest ability to colonize at increasing distance,whereas A. denticulata was intermediate. In the presence of the collembolan, G. etunicatum took longer to colonize neighbouring plants, but was able to infect at least 30 cm further, illustrating the arthropod's ability to disperse the AM inoculum. A. denticulata increased its range by 10 cm in the presence of F. candida, but unlike G. etunicatum, there was no delay in the colonization. In contrast, colonization of neighbouring plants by S. calospora was negatively affected both in terms of overall distance and time. These data support the hypothesis that soil arthropods can act as dispersal agents for AM inoculum, but the extent of this is fungal species-specific. Received: 1 July 1998  相似文献   

13.
The behavior of soil organisms inhabiting soil pore spaces can be influenced by soil compression, which can affect their avoidance behavior to pollutants. In this study, we aimed to evaluate the effect of soil compression on the avoidance behavior of Allonychiurus kimi (Collembola) to heavy metals cadmium and copper. Initially, to assess the applicability of the avoidance test guideline of the International Organization for Standardization (ISO) developed for Folsomia candida, we investigated the avoidance behavior of A. kimi to cadmium and copper in an artificial soil with a loose structure (bulk density of 0.25 g cm-3), the porous texture of which was sufficiently loose to enable A. kimi to move between pore spaces. The effect of soil compression on the avoidance behavior of A. kimi to both metals was evaluated in compressed soil (bulk density of 0.64 g cm-3) with a uniformly compressed soil surface, and avoidance behavior was investigated at 24-h intervals over a 120-h period. Given that A. kimi is unable to burrow into compressed soil, the compressed soil test can minimize the effects of differences in soil factors, such as soil porosity and bulk density, on the behavior of this collembolan. In the artificial soil, a statistically significant avoidance behavior of A. kimi was observed at cadmium and copper concentrations greater than 50 and 200 mg kg-1, respectively, thereby indicating the applicability of the ISO avoidance test guidelines for A. kimi. When compared at the same exposure time point, the avoidance response to both metals in compressed soil was less sensitive than that in uncompressed soil. In addition, we observed differences in the effects of metals on avoidance response in the compressed soil over time, with the effect of cadmium increasing with time and the effect of copper showing the opposite trend. Overall, we found that soil compression can affect the avoidance behavior of A. kimi to cadmium and copper, and we discussed the advantages and limitations of using compressed soil for assessments of pollutant toxicity.  相似文献   

14.
In order to measure the genetic variability and determine the evolutionary relationships among strains of the parthenogenetic “standard” springtail Folsomia candida, we used Random Amplified Polymorphic DNA (RAPD-PCR) markers and determined the nucleotide sequence of the 18S and 28S rDNA genes. Both types of molecular characters were found to be polymorphic. We obtained phylogenetic trees using Direct Optimization in the dynamic homology paradigm. The trees were polarized with Isotoma viridis as an outgroup. All the trees based on one or the other type of molecular characters or based on all characters pooled together, support the hypothesis of an early divergence of two distinct lineages among the 11 strains of F. candida under study. Our results also suggest that these lineages differ in their rate of evolution and mode of diversification. The geographical origin of the studied strains was examined but we found no clear relation between the phylogenetic relationships and probable geographical origins. The early divergence of several lineages in this species should be taken into account when comparing studies on genetically different strains of this model organism. RAPD-PCR typing is an easy and efficient tool for doing such a task.  相似文献   

15.
Combined compound-specific stable carbon isotopic methods and fatty acid abundance determinations have been used to examine feeding preferences and C allocation in organisms where direct observation of feeding is difficult. In order to examine the effect of differing diets on the δ13C values of fatty acids and sterols of Collembola, the diets of two collembolan species, Folsomia candida and Proisotoma minuta, were switched from a yeast diet to one of four isotopically distinct diets, and the δ13C values of the lipids monitored over the next 39 d. Cholesterol remained the only sterol detected in both collembolan species, despite the diets containing widely differing sterol compositions. The δ13C values of collembolan lipids recorded after long term feeding were often different to those of the same components in the diet, indicating that fractionation or partitioning occurs during digestion, assimilation and biosynthesis within the Collembola, thereby shifting consumer lipid δ13C values away from those of the corresponding dietary components. The rates of change of δ13C values differed among compounds, with half-lives ranging between 29 min and 14 d. Some of these differences appear to be related to the abundance of dietary components, such that fatty acids present in high abundance in the diet (e.g. 18:2(n−6)) were rapidly assimilated in high proportions into collembolan lipids, leading to a rapid change in δ13C values. Similarly, isotopic turnover in the 16:1(n−7) fatty acid, present in the newly presented diets in only low abundances, was significantly correlated to the rate of removal of this component from the consumer fatty acid pool. The rates of change of δ13C values in P. minuta lipids did not vary significantly with diet, whilst the rates of change of δ13C values of lipids in F. candida were affected by the diets the Collembola consumed. Results of an experiment providing F. candida and P. minuta with two diets of different quality demonstrated that F. candida responded to the high quality diet with increased growth and fecundity, whilst P. minuta responded with increased fecundity only. Thus, the abilities of the two species to respond to diets of varying quality, amongst other factors, is concluded to lead to differences in the rates of change of δ13C values reflecting differences in lipid turnover.  相似文献   

16.
We examined collembolan food preference for fungal mycelium grown on copper-contaminated medium, and the relationship between copper content, food selectivity and collembolan fitness when fed contaminated mycelium.To clarify whether collembolan food selectivity is related to fitness parameters, Folsomia candida were fed mycelium of the dark-pigmented fungus Alternaria alternata grown on medium with different copper concentrations. Copper-contaminated food (fungus grown on 50, 125, 250 and 500 μg Cu g−1 medium, fresh wt.) was offered together with untreated food for 4 weeks. F. candida fed selectively on the provided mycelium and discriminated clearly between mycelium grown on high and low levels of contamination, distinctly preferring fungus grown on medium with a total copper concentration of 50 and 125 μg g−1. In contrast, fungus grown on highly contaminated medium (250 and 500 μg g−1) was avoided. Collembolan food preference generally matched fitness parameters. Reproduction was significantly affected by the total copper concentration of the fungal growth medium. When fed their preferred mycelium, collembolan reproduction was enhanced, whereas a diet of highly contaminated mycelium (250 or 500 μg g−1) resulted in a strong decrease in reproduction. Adult survival was affected only marginally. Even though heavy metal contamination is a potential stress factor for many soil microarthropods, F. candida is able to discriminate between high and low quality food sources, and even benefits from moderately elevated copper concentrations.  相似文献   

17.
The basidiomycete Strobilurus ohshimae has fruiting bodies covered with prominently projecting hair-like cells called cystidia; it is not consumed by the collembolan Ceratophysella denisana but is consumed by Mitchellania pilosa. To explain this difference, we examined the effects of S. ohshimae cystidia on collembolan survival. In the field, several collembolan species, including C. denisana, were found dead on S. ohshimae, whereas no dead M. pilosa were found on the fungus. Survival of M. pilosa on S. ohshimae was 100%. In the laboratory, cystidium destruction experiments showed that the cystidia of S. ohshimae were capable of killing C. denisana on contact. A cystidium contact time experiment revealed that the cystidia were also capable of killing M. pilosa, although M. pilosa could survive when the contact time was short. In the field, M. pilosa frequently fed on the interior of S. ohshimae. Interior feeding may enable M. pilosa to feed on S. ohshimae by reducing contact time with the cystidia. The deadly surface of S. ohshimae deters the surface feeder C. denisana but not the interior feeder M. pilosa, resulting in food differentiation of these collembolans.  相似文献   

18.

Purpose  

A contaminated soil was amended to reduce bioavailability of metals (As, Cd, Cu, Pb, and Zn) and to modify its potential environmental impacts. Reproduction toxicity tests using two different soil invertebrates, Enchytraeus crypticus and Folsomia candida, were used to evaluate efficiency of soil amendments to reduce metal availability.  相似文献   

19.
The effect of microarthropod density on the relative palatibility of selected microfungi and on the integrity of extraradical arbuscular-mycorrhizal (AM) hyphal networks was examined. A series of microcosm experiments were conducted using two conidial fungi (Alternaria alternata and Trichoderma harzianum), one AM fungus (Glomus intraradices) and the microarthropod Folsomia candida (Collembola). We did not detect a significant effect of athropod density on food preference. Food preferences for conidial over mycorrhizal hyphae were consistent across a wide range of collembolan densities. Collembolan density did, however, have a significant effect on the numbers of extraradical AM hyphae which were severed from the plant root in vitro. Even in the presence of a preferred food source, numbers of severed AM hyphal networks increased with increasing collembolan density. Also, the fecundity of Folsomia candida increased in the presence of preferred food sources. We conclude that microarthropod population densities are influenced by the fungal species available and that the potential of microarthropods to impair the efficacy of AM symbioses is density-dependent. Received: 16 May 1997  相似文献   

20.
Degradation factors can cause both quantitative and qualitative changes in fauna and thus affect soil functioning. The use of bio-indicators may help to detect environmental changes. The aim of this study was to evaluate the effects of lead and cadmium on the biology (mortality, reproduction, egg hatching) of two euedaphic collembolans, Sinella coeca and Folsomia candida and to evaluate sensitivity differences between the two species. The results showed that low concentrations of lead did not cause dramatic effects on the survival and reproduction of both species. Reproduction of both species was reduced when the soil contained a nominal concentration of Pb at 1000 μg g–1. S. coeca and F. candida showed a high sensitivity to cadmium and both their reproduction and survival were significantly reduced on exposure to 50 μg g–1. Moreover, egg hatching of F. candida was affected by the cadmium concentrations in the soil, and by the amount of time that the eggs stayed in contact with cadmium. This study showed that the inhibition determined by Cd on F. candida juvenile production was caused in part by inhibition of deposition and, in part, by reduction of egg viability.  相似文献   

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