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981.
Individual performance defines population dynamics. Condition index – a ratio of weight and some function of length – has been louded as an indicator of individual performance and recommended as a tool in fisheries management and conservation. However, insufficient understanding of the correlation between individual-level processes and population-level responses hinders its adoption. To this end, we use composite modelling to link individual's condition, expressed through the condition index, to population-level status. We start by modelling ontogeny of European pilchard (Sardina pilchardus, Clupeidae) as a function of food and constant temperature using Dynamic Energy Budget theory. We then provide a framework to simultaneously track the individual- and population-level statistics by incorporating the dynamic energy budget model into an individual-based model. Lastly, we explore the effects of fishing pressure on the statistics in two constant and food-limited environmental carrying capacity scenarios. Results show that, regardless of the species' environmental carrying capacity, individual condition index will increase with fishing mortality, that is, with reduction of stock size. Same patterns are observed for gilthead seabream (Sparus aurata, Sparidae), a significantly different species. Condition index can, therefore, in food-limited populations, be used to (i) estimate population size relative to carrying capacity and (ii) distinguish overfished from underfished populations. Our findings promote a practical way to operationally incorporate the condition index into fisheries management and marine conservation, thus providing additional use for the commonly collected biometric data. Some real-world applications, however, may require additional research to account for other variables such as fluctuating environmental conditions and individual variability. 相似文献
982.
Vesna Ilić Zoran Šaponjić Vesna Vodnik Darka Mihailović Petar Jovančić Jovan Nedeljković Maja Radetić 《Fibers and Polymers》2009,10(5):650-656
The aim of this study was to examine the influence of dyeing on antibacterial efficiency of corona activated polyamide and polyester fabrics loaded with colloidal Ag nanoparticles as well as the influence of the presence of Ag nanoparticles on the color change of dyed fabrics. C.I. Acid Green 25 and C.I. Disperse Blue 3 were used for dyeing of polyamide fabrics and C.I. disperse violet 8 for polyester fabrics. The color change of polyamide fabrics depends on the dye type, which was generally lower compared to polyester fabrics. Antibacterial efficiency of Ag loaded fabrics was tested against Gram-positive bacterium Staphylococcus aureus and Gram-negative bacterium Escherichia coli. Corona activated polyester and polyamide fabrics showed excellent antibacterial efficiency independently of order of dyeing and Ag loading. The morphology of fibers loaded with Ag nanoparticles was assessed by SEM and atomic absorption spectroscopy for elemental analysis. 相似文献
983.
Irena Mavrič Pleško Mojca Viršček Marn Saša Širca Gregor Urek 《European journal of plant pathology / European Foundation for Plant Pathology》2009,123(3):261-268
In 2003, Raspberry bushy dwarf virus was found for the first time in grapevine. Since this was the first report of a non-Rubus natural host, information about it is sparse. During this study the grapevine isolates were characterised biologically, serologically
and genetically and compared with known information about Rubus isolates. Infected plant material was used for mechanical inoculation of test plants, and for serological characterisation
with monoclonal antibodies. Most of RNA 2 was sequenced and compared with other sequences from the database. Grapevine isolates
infected Chenopodium murale systemically, which is not known for raspberry isolates. They were differentiated from Slovenian raspberry isolates with
three monoclonal antibodies using TAS-ELISA. Phylogenetic analyses clustered grapevine isolates separately from raspberry
isolates. Additionally, the virus was detected using nested RT-PCR in Longidorus juvenilis nematodes collected in an infected vineyard. Grapevine isolates of RBDV are distinct from raspberry isolates. 相似文献
984.
Ladislav Cséfalvay Gabriele Di Gaspero Karel Matouš Diana Bellin Benedetto Ruperti Julie Olejníčková 《European journal of plant pathology / European Foundation for Plant Pathology》2009,125(2):291-302
Plasmopara viticola is an economically important pathogen of grapevine. Early detection of P. viticola infection can lead to improved fungicide treatment. Our study aimed to determine whether chlorophyll fluorescence (Chl-F)
imaging can be used to reveal early stages of P. viticola infection under conditions similar to those occurring in commercial vineyards. Maximum (FV/FM) and effective quantum yield of photosystem II (ΦPSII) were identified as the most sensitive reporters of the infection. Heterogeneous distribution of FV/FM and ΦPSII in artificially inoculated leaves was associated with the presence of the developing mycelium 3 days before the occurrence
of visible symptoms and 5 days before the release of spores. Significant changes of FV/FM and ΦPSII were spatially coincident with localised spots of inoculation across the leaf lamina. Reduction of FV/FM was restricted to the leaf area that later yielded sporulation, while the area with significantly lower ΦPSII was larger and probably reflected the leaf parts in which photosynthesis was impaired. Our results indicate that Chl-F can
be used for the early detection of P. viticola infection. Because P. viticola does not expand systemically in the host tissues and the effects of infection are localised, Chl-F imaging at high resolution
is necessary to reveal the disease in the field. 相似文献
985.
Č. Radenović M. Filipović V. Andjeković M. Babić A. Radojčić 《Russian Agricultural Sciences》2009,35(6):374-377
Data are given on the dynamics of water loss from grain of elite maize lines during ripening and on their photosynthetic-fluorescence
properties based on the effects and nature of structural and functional changes in thylakoid membranes and chemical structures
of grain tissues. 相似文献
986.
The efficacy of juvenile hormone III (JH III) and two JH-mimicking compounds was compared in laboratory experiments with Reticulitermes lucifugus (Rossi), R. santonensis Feytaud and R. virginicus (Banks). Induction of presoldier, soldier and/or soldier-worker intercaste differentiation was taken as positive response to the treatment. The novel juvenogen, a fatty acid ester of a juvenoid alcohol, induced greatest soldier differentiation in all species tested, followed by hydroprene. JH III was less effective. Representatives of three Reticulitermes species showed similar trends in soldier induction rates. Differences in mortality in treatments of termites of the same species from different colonies with the same compound were observed and evidently were caused by differences in the conditions of respective colonies. 相似文献
987.
Panita Prathomya Wassana Prisingkorn Ivan Jakovlić Fang-Yu Deng Wei-Min Wang 《Journal Of Applied Aquaculture》2013,25(3):254-270
ABSTRACTFish meal is the main protein source in fish diet, but due to its unsustainability, it has to be replaced with more sustainable protein sources, such as soybean meal (SBM), in fish feeds. As SBM often produces negative effects on fish growth and health, we conducted an eight-week trial of complete fish meal replacement with SBM in the diet of juvenile (48.2 ± 0.55 g) blunt snout bream (Megalobrama amblycephala), a herbivorous cyprinid fish native to the Yangtze basin (China). SBM-fed fish exhibited: a worsened growth performance; improved survival rate (P > 0.05); elevated serum triglycerides and total cholesterol but reduced low-density lipoprotein in plasma (P < 0.05); mild lipid droplet accumulation and swelling of the liver; elevated goblet cell counts and mild signs of enteritis in the intestines. With negligible effects on growth and mild effects on health, M. amblycephala appears to be comparatively tolerant of SBM, but total fish meal replacement is not recommended. Future studies should aim to identify the SBM tolerance threshold in long-term growth trials. 相似文献
988.
989.
Slovenia has no history of health problems related to proliferative kidney disease (PKD) either in farmed or in wild fish. However, due to the past molecular evidence for the presence of Tetracapsuloides bryosalmonae DNA in tissues of some fish from open waters, a survey was conducted on wild salmonids that were primarily sampled for other purposes. In winter 2010–2011, specimens from a total of 244 rainbow trout, Oncorhynchus mykiss (Walbaum), and brown trout, Salmo trutta L., from 30 bodies of fresh water were examined for T. bryosalmonae using a PCR method. The sampled fish showed no clinical signs or gross pathological lesions characteristic of PKD. Nineteen (7.8%) fish from seven (23.3%) fresh waters were positive for T. bryosalmonae. The identity of PCR amplicons was confirmed by sequencing. With one exception, all the positive fish were found in waters from the regions where the average yearly temperatures and the environmental pollution are higher. This preliminary countrywide survey provided the first insight into the situation regarding T. bryosalmonae infection of wild salmonids in Slovenia. 相似文献
990.
Eight aphid species were determined as new records for Serbia as a result of the evaluation of the specimens caught by yellow water traps used for monitoring vector activities in seed potato crops during the 4 years 2007–2010. The invasive aphid species Macrosiphum albifrons Essig 1911; and the new species Acyrthosiphon cyparissiae (Koch 1855), Ctenocallis setosus (Kaltenbach 1846), Myzodium modestum (Hottes 1926), Myzocallis castanicola Baker 1917, Myzocallis occidentalis Remaudiè et Nieto Nafria 1974, Tinocallis platani (Kaltenbach 1843) and Wahlgreniella ossiannilssoni Hille Ris Lambers 1949. M. modestum is very difficult to detect, as it lives hidden in moss. All species are presented with characteristic morphological information of alatae and line drawings. 相似文献