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101.
Jörg Römbke 《人类与生态风险评估》2006,12(1):84-101
Until recently, only a small number of standardized (mainly acute) tests with earthworms and plants were available for terrestrial risk assessment. However, during the last years various new methods (especially with chronic endpoints such as reproduction) were developed and standardized. Moreover, beyond structural aspects (e.g., the effect on individuals), the question of influences of chemicals on ecological soil functions like litter decomposition has been raised. Later, biological test methods were used in the area of Soil Quality Assessment, where an often unknown and complex contamination of a site-specific field soil has to be evaluated. Due to the variety of soils to be tested, the existing methods had to be adapted. This article briefly summarizes basic principles of method standardization before providing an overview of existing standardized tests for the compartment soil (mainly from Europe), focusing on zoological, plant, and functional methods. After presenting the main features of already standardized tests (in particular those used in soil quality assessment so far) the development of new tests for specific purposes, ideas for a battery of tests and a new, community-based approach assessing the biological quality of field soils are discussed. 相似文献
102.
Spatial and temporal variation in critical life history traits differ markedly between two co-occurring, rare and endangered annual plants, Gilia tenuiflora arenaria and Chorizanthe pungens pungens, that have restricted, but overlapping geographic distributions in coastal habitats of central California, USA. Environmental variation was extreme during the 6-year study (1997–2002), with the greatest differences between an intense wet, warm El Niño year (1998), followed by a very dry, cool La Niña (1999). Both species have similar increases in adult survival and seed set with wetter, warmer weather in spring, but they differed in other traits: more Gilia germinated in years with high rainfall and temperature, while more Chorizanthe germinated in dry, cooler years; Gilia abundance increased with the number of years since the previous large El Niño event, while Chorizanthe abundance declined; and Gilia abundance was independent of the previous year’s seed set, while Chorizanthe density was directly related to the previous year’s seed set. The strong negative associations of Chorizanthe abundance with warm, wet weather and with time since the previous El Niño probably reflect the particular sequence of annual weather patterns from 1997 through 2002, especially the extremes in 1998 and 1999. Since it germinates readily in most years under a wide range of winter conditions and does not develop a long-lived seed bank, Chorizanthe seedling abundance reflects recent additions and depletions of its seed bank, rather than prevailing weather, per se. In contrast, Gilia seeds may remain in the seed bank for many years, until relatively rare winter conditions trigger significant germination. These species-specific demographies enhance persistence and coexistence of these species, but the mechanisms differ from each other and from those described for annuals in other highly variable environments. 相似文献
103.
Dariusz Pańka Dariusz PiesikMałgorzata Jeske Anna Baturo-Cieśniewska 《Journal of plant physiology》2013
Grasses very often form symbiotic associations with Neotyphodium/Epichloë endophytic fungi. These endophytes often allow the host grass to be protected from different pathogens. However, there is little known about the mechanisms of such endophyte influence on the host. Thus, the purpose of this research was to examine the effect of the N. lolii endophyte on the total production of phenolic compounds, VOCs emission and the resistance of three perennial ryegrass genotypes infected by pathogenic Fusarium poae. Analyses of total phenolics content were performed in control (not inoculated) and inoculated plants after 1, 2, 3, 4, 5, and 6 days (DAI) and for VOCs after 0, 3, 6 and 12 DAI. The presence of endophytes significantly reduced the disease index in two of the three genotypes relative to that in E−. Plants infected by N. lolii exhibited higher production of phenolics relative to the E− plants. The highest amounts of phenolics were observed on the second and sixth DAI. Genotype Nl22 showed the strongest effect of the endophyte on the production of phenolics, which increased by over 61%. Both the endophyte infected and non-infected plants emitted most abundantly two GLVs ((Z)-3-hexenal, (Z)-3-hexen-1-yl acetate), three terpenes (linalool, (Z)-ocimene, β-caryophyllene) and three shikimic acid pathway derivatives (benzyl acetate, indole, and methyl salicylate). The endophyte presence and the intervals of VOCs detection were a highly significant source of variation for all emitted volatiles (P < 0.001). The genotype of the perennial ryegrass significantly affected only the emission of methyl salicylate (P < 0.05) and β-caryophyllene (P < 0.05). Most of the VOCs ((Z)-3-hexen-1-yl acetate, (Z)-3-hexenal, linalool and methyl salicylate) reached their highest levels of emission on the sixth DAI, when averaged over genotypes and endophyte status. The results highlight the role of Neotyphodium spp. in the mediation of quadro-trophic interactions among plants, symbiotic endophytes, invertebrate herbivores and plant pathogenic fungi. Our results also confirm the fact that symbiotic plants can activate a defense reaction faster than non-symbiotic plants after a pathogen attack. Thus, N. lolii can be involved in the defense of perennial ryegrass against pathogens and potentially could be central to the host plants’ protection. 相似文献
104.
Shabir A. Lone A.S. Yadav A. Bajaj Ajit K. Sharma Yogesh Badkhane D.K. Raghuwanshi 《Archives Of Phytopathology And Plant Protection》2013,46(11):1327-1340
Over-utilisation and continuous depletion of medicinal plants have affected their supply and loss of genetic diversity. Hence the current study is based on conservation strategies for threatened medicinal plants with special reference to Barleria prionitis L. using in vitro and ex vitro propagation techniques. We have developed here a protocol for plant regeneration of Barleria prionitis L. We have also developed an efficient system of vegetative propagation of Barleria prionitis L. through stem cuttings using revive rooting hormones. These studies can be useful for conservation strategies of this important medicinal plant. 相似文献
105.
Yi Wang Juli Carrillo Evan Siemann Gregory S. Wheeler Lin Zhu Xue Gu Jianqing Ding 《Annals of botany》2013,112(4):751-756
Background and Aims
Invasive plants can be released from specialist herbivores and encounter novel generalists in their introduced ranges, leading to variation in defence among native and invasive populations. However, few studies have examined how constitutive and induced indirect defences change during plant invasion, especially during the juvenile stage.Methods
Constitutive extrafloral nectar (EFN) production of native and invasive populations of juvenile tallow tree (Triadica sebifera) were compared, and leaf clipping, and damage by a native specialist (Noctuid) and two native generalist caterpillars (Noctuid and Limacodid) were used to examine inducible EFN production.Key results
Plants from introduced populations had more leaves producing constitutive EFN than did native populations, but the content of soluble solids of EFN did not differ. Herbivores induced EFN production more than simulated herbivory. The specialist (Noctuid) induced more EFN than either generalist for native populations. The content of soluble solids in EFN was higher (2·1 times), with the specialist vs. the generalists causing the stronger response for native populations, but the specialist response was always comparable with the generalist responses for invasive populations.Conclusions
These results suggest that constitutive and induced indirect defences are retained in juvenile plants of invasive populations even during plant establishment, perhaps due to generalist herbivory in the introduced range. However, responses specific to a specialist herbivore may be reduced in the introduced range where specialists are absent. This decreased defence may benefit specialist insects that are introduced for classical biological control of invasive plants. 相似文献106.
Raivo Kalle Renata Sõukand 《Botanical journal of the Linnean Society. Linnean Society of London》2013,172(2):239-253
In this ethnobotanical study, the authors provide the first quantitative analysis of the use of wild edible plants in Estonia, describing the domains and assessing the food importance of different species. The information was collected using free‐listing written questionnaires and concerned plants used by the respondents in their childhood. As part of a major study, this article covers the responses of professionals with some botanical education at vocational or university level, to ensure the greatest possible reliability without using voucher specimens. Fifty‐eight respondents provided information on the use of 137 plant taxa, corresponding to approximately 6% of the native and naturalized vascular plants of Estonia. According to use frequency, the most typical wild food plant of Estonia is a fruit, eaten raw as a snack. The results clearly signal that the majority of famine and food shortage plants had already been forgotten by the end of the 20th century, but new plants have been introduced as green vegetables for making salads. Despite changes in the nomenclature of the plants, the use of wild food plants in Estonia was still thriving at the turn of the 20th century, covering many domains already forgotten in urbanized modern Europe. © 2013 The Linnean Society of London, Botanical Journal of the Linnean Society, 2013, 172 , 239–253. 相似文献
107.
Bryan C. Carstens Jordan D. Satler 《Biological journal of the Linnean Society. Linnean Society of London》2013,109(4):737-746
Modern methods for species delimitation provide biologists with the power to detect cryptic diversity in nearly any system. To illustrate the application of such methods, we collected data (21 sequence loci) from a carnivorous plant in southeastern North America and applied several recently developed methods (Gaussian clustering, Structurama, BPP, spedeSTEM). The pale pitcher plant Sarracenia alata inhabits the southeastern USA along the northern coast of the Gulf of Mexico. Sarracenia alata populations are separated by the Mississippi River and Atchafalaya Basin, a known biogeographical barrier in this region, but the cohesiveness of S. alata as currently classified has not been tested rigorously. Multiple analytical approaches (including allelic clustering and species trees methods) suggest that S. alata comprises two cryptic lineages that correspond to the eastern and western portions of the plant's distribution. That such clear genetic evidence for cryptic diversity exists within S. alata and is in conflict with other sources of data (e.g. morphology, environmental differentiation) illustrates a conundrum faced by those who investigate species boundaries: genetic data are often the first type of data to accumulate evidence of differentiation, but most existing taxonomic treatments are based on nongenetic data. Our results suggest that S. alata as currently described contains two cryptic species, and we recommend the elevation of the western populations to species status. © 2013 The Linnean Society of London, Biological Journal of the Linnean Society, 2013, 109 , 737–746. 相似文献
108.
Daniela Guicking Brigitte Fiala Tim Kröger‐Kilian Maryati Mohamed Kurt Weising 《Botanical journal of the Linnean Society. Linnean Society of London》2013,173(4):606-621
As a result of intensive exploitation, disturbed forests now dominate large areas of lowland tropical rainforest in South‐East Asia. The genus Macaranga comprises some of the most important pioneer tree species of the region, among them M. beccariana and M. hypoleuca, two closely related obligate ant‐plants pollinated by thrips. We used nuclear and plastid DNA markers to address questions of genetic diversity and population structure. Twelve plastid haplotypes were detected among 281 samples, three of which were shared between the two study species. Hybrids between the two species appear to be rare. Overall, genetic diversity in both species was moderate to high, with low levels of population differentiation, consistent with other tropical pioneer trees. Genetic structure was generally more pronounced in plastid than in nuclear data, indicating that gene flow via pollen may be more efficient than via seeds. Thrips apparently also serve as efficient pollinators over long distances, perhaps through a combination of passive dispersal by wind and active search for inflorescences in the target area. Our results indicate that M. beccariana and M. hypoleuca populations from recently disturbed habitats do not yet suffer from reduced genetic diversity or increased inbreeding. © 2013 The Linnean Society of London, Botanical Journal of the Linnean Society, 2013, 173 , 606–621. 相似文献
109.
《Bioscience, biotechnology, and biochemistry》2013,77(7):1494-1497
To clarify the involvement of seven Arabidopsis homologs of rat L-gulono-1,4-lactone (L-GulL) oxidase, AtGulLOs, in the biosynthesis of L-ascorbic acid (AsA), transgenic tobacco cells overexpressing the various AtGulLOs were generated. Under treatment with L-GulL, the levels of total AsA in three transgenic tobacco cell lines, overexpressing AtGulLO2, 3, or 5, were significantly increased as compared with those in control cells. 相似文献
110.
Pipecolic acid naturally occurs in microorganisms, plants, and animals, where it plays many roles, including the interactions between these organisms, and is a key constituent of many natural and synthetic bioactive molecules. This article provides a review of current knowledge on the natural occurrence of pipecolic acid and the known and potential significance of its L‐ and D‐enantiomers in different scientific disciplines. Knowledge gaps with perspectives for future research identified within this article include the roles of the L‐ versus the D‐enantiomer of pipecolic acid in plant resistance, nutrient acquisition, and decontamination of polluted soils, as well as rhizosphere ecology and medical issues. Chirality 25:823–831, 2013. © 2013 Wiley Periodicals, Inc. 相似文献