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22. A "clean" alien species? Parasites of the invasive ladybird Harmonia axyridis (Coleoptera: Coccinellidae)
- Creator:
- Dudek, Kryzstof, Sienkiewicz, Paweł, Gwiazdowicz, Dariusz J., and Piotr Tryjanowski
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, brouci, slunéčkovití, slunéčko východní, hlístice, beetles, Coccinellidae, Harmonia axyridis, Nematodes, phoretic mites, insect ecology, eugregarines, fungi, 2, and 59
- Language:
- English
- Description:
- The multicoloured Asian ladybird Harmonia axyridis is an invasive insect that can negatively influence biodiversity and human economy in invaded areas. According to the enemy release hypothesis, invasive alien species are often little affected by parasites and other enemies. We studied the prevalence of common parasites of insects infesting and infecting H. axyridis in NW Poland. A large sample of 2351 individuals was collected and divided into two groups: 1180 beetles were dissected and examined for the presence of eugregarines, nematodes and Laboulbeniales fungi, and 751 were checked for phoretic mites. Our results show that H. axyridis is indeed parasitized infrequently. The prevalence of eugregarines and nematodes was very low (1.5% and 0.4%, respectively). No specimens of Laboulbeniales or phoretic mites were found. Our study indicates that in NW Poland H. axyridis is rarely infested or infected by parasites. This paper reports for the first time the infection of H. axyridis by the eugregarine Gregarina barbarara., Kryzstof Dudek, Paweł Sienkiewicz, Dariusz J. Gwiazdowicz, Piotr Tryjanowski., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
23. A case study of Heleomyzidae (Diptera) recorded on snow in Poland with a review of their winter activity in Europe
- Creator:
- Soszńska-Maj, Agnieszka and Woźnica, Andrzej J.
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, dvoukřídlí, fenologie, Diptera, phenology, Evropa, Polsko, Europe, Poland, Heleomyzidae, winter activity, snow fauna, 2, and 59
- Language:
- English
- Description:
- Twenty eight species of winter-active Heleomyzidae were collected during a long-term study in Poland. More than 130 samples of insects, including Heleomyzidae, were collected from the surface of snow in lowland and mountain areas using a semi-quantitative method. Lowland and mountain assemblages of Heleomyzidae recorded on snow were quite different. Heleomyza modesta (Meigen, 1835) and Scoliocentra (Leriola) brachypterna (Loew, 1873) dominated in the mountains, Tephrochlamys rufiventris (Meigen, 1830) mainly in the lowlands and Heteromyza rotundicornis (Zetterstedt, 1846) was common in both habitats. Heleomyzidae were found on snow during the whole period of snow cover, but the catches peaked from late November to the beginning of February. In late winter and early spring the occurrence of heleomyzids on snow decreased. Most individuals were active on snow at air temperatures between -2 and +2.5°C. A checklist of 78 winter active European Heleomyzidae is presented. Helomyza nivalis Wahlgren, 1918 is herein considered as a new junior synonym of Helomyza caesia Meigen, 1830, syn. n., Agnieszka Soszyńska-Maj, Andrzej J. Woźnica., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
24. A comparison of chlorophyll fluorescence transient measurements, using Handy PEA and FluorPen fluorometers
- Creator:
- Padhi, B., Chauhan, G., Kandoi, D., Stirbet, A., Tripathy, Baishnab C., and Govindjee, G.
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- huseníček rolní, Arabidopsis thaliana, blue and red excitation light, fluorescence imaging, OJIP transient, 2, and 581
- Language:
- Multiple languages
- Description:
- We provide here a general introduction on chlorophyll (Chl) a fluorescence, then we present our measurements on fast (< 1 s) induction curves (the so-called OJIP transients) on dark-adapted intact leaves of Arabidopsis thaliana, under five different light intensities [in the range of ~ 500 to ~ 3,000 µmol(photons) m‒2 s‒1] using two different instruments: Handy PEA (Hansatech Instruments, UK; excitation light, 650 nm) and FluorPen (model FP-110; Photon Systems Instruments, The Czech Republic; excitation light, 470 nm). We then discuss the observed differences in the OJIP curves, as well as in Fo (F20μs, F50μs, or the extrapolated Ft→0), FP (the peak), and the ratios FP/Fo, and Fv (= FP ‒ Fo)/FP in terms of differences in excitation light intensity and absorptance (or absorbance) of the excitation light by the leaves, and other factors, as well as the data available in the literature. We suggest that such measurements be accompanied, in the future, by parallel measurements on Chl a fluorescence imaging, an area pioneered by Hartmut K. Lichtenthaler., B. Padhi, G. Chauhan, D. Kandoi, A. Stirbet, B. C. Tripathy, G. Govindjee., and Obsahuje bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
25. A comparison of seasonal foliar chlorophyll change among ecotypes and cultivars of Andropogon gerardii (Poaceae) by using nondestructive and destructive methods
- Creator:
- Caudle, K. L., Johnson, L. C., Baer, S. G., and Maricle, B. R.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- fotosyntéza, sucha, travní porosty, populace (biologie), pigmenty, rostliny prérií, photosynthesis, grasslands, population (biology), pigments, prairies plants, drouhgt, prairie, precipitation gradient, sand bluestem, tallgrass prairie, Andropogon gerardii, 2, and 581
- Language:
- Multiple languages
- Description:
- Leaf chlorophyll (Chl) concentration can be an indicator of plant health, including photosynthetic potential and nutrient status. In some cases, this measure can indicate the degree to which plants are water-stressed. Traditional methods of measuring Chl concentration have involved a destructive sampling technique: extraction and spectrophotometric analysis. A compatible nondestructive method to measure leaf Chl concentration exists and applies transmittance spectroscopy to plants with a Minolta SPAD-502 meter. These techniques were evaluated by comparing leaf Chl concentration in big bluestem (Andropogon gerardii). Leaves were sampled from plants representing three ecotypes (originating from Central Kansas, Eastern Kansas, and Illinois, USA) and two cultivars of A. gerardii growing in Hays, Kansas, USA. Leaf Chl concentration was measured using nondestructive and destructive techniques. We documented a saturating relationship between destructively measured leaf Chl concentration and SPAD index resulting from a decelerating change in SPAD index as Chl concentration increased. The comparison of A. gerardii ecotypes and cultivars demonstrated highest Chl concentration in the ecotype and cultivar from areas with historically low precipitation, Central Kansas and A. gerardii var. hallii, respectively. A high ratio of Chl a to Chl b is an index of drought adaptation and was also manifested in A. gerardii from drier regions. Thus, drought-adapted ecotypes and cultivars might be able to maintain high photosynthetic productivity and protect photosystem II during dry periods. Conversely, the ecotypes and cultivar originating from areas with higher precipitation had lower leaf Chl and a lower Chl a/b ratio., K. L. Caudle, L. C. Johnson, S. G. Baer, B. R. Maricle., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
26. A little further south: Host range and genetics of the Northern pine processionary moth, Thaumetopoea pinivora (Lepidoptera: Notodontidae) at the southern edge of its distribution
- Creator:
- Hógar, José A., Cassel-Lundhagen, Anna, Battisti, Andrea, and Larsson, Stig
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, motýli, odlesňování, butterflies, deforestation, Lepidoptera, Notodontidae, Thaumetopoea pinivora, genetic diversity, host shift, marginal woodlands, relict populations, 2, and 59
- Language:
- English
- Description:
- The Northern pine processionary moth, Thaumetopoea pinivora (Treitschke, 1834) shows a highly scattered distribution with fragmented populations across Europe. A previous study exploring the postglacial history of T. pinivora defined it as a cold-tolerant relict species and concluded that a progressive reduction of suitable habitats after the postglacial expansion from refugia in the southern Iberian peninsula best explained the distribution and genetic structure of populations of this species. However, recent records, both by us and others, challenge this view. Surprisingly, some of the newly found populations from southern Spain use black pine, Pinus nigra J.F. Arnold as a host plant despite the fact that the typical host of the species, Scots pine, Pinus sylvestris L. occurs in the area. We provide genetic data for one of these recently found southern populations where the larvae feed on P. nigra, and compare this with previously published data on individuals collected on P. sylvestris. This data reveals that populations from different host trees are no more genetically differentiated than populations sharing the same host plant. The findings of a wider diet breadth open the way to widen the search for the still unidentified glacial refugium of T. pinivora, and as such may contribute to a better understanding about how the species has spread across Europe., José A. Hódar, Anna Cassel-Lundhagen, Andrea Battisti, Stig Larsson., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
27. A marine phytoplankton Prymnesium parvum upregulates the component proteins of photosystem II under iron stress
- Creator:
- Rahman, M. M., Rahman, M. A., Maki, T., Nishiuchi, T., Asano, T., and Hasegawa, H.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- fotosyntéza, fytoplankton, železo, photosynthesis, phytoplankton, iron, Japonsko, Hirošima (Japonsko), Japan, mořský fytoplankton, Fe limitation, growth rate, protein expression, Prymnesium parvum, marine phytoplankton, Fukuyama Bay, 2, and 581
- Language:
- Multiple languages
- Description:
- Iron is an essential limiting factor for primary production in many marine systems. The present study investigated differential regulation of protein expression in marine phytoplankton Prymnesium parvum under low Fe concentration. The phytoplankton was grown in f/2 culture medium in artificial seawater with low (0.0025 μM) and high (0.05 μM) Fe concentrations. Two-dimensional differential gel electrophoresis and matrix-assisted laser desorption-ionization-time of flight-mass spectrometer analysis were performed for protein identification and characterization. The growth of the alga declined substantially under the low Fe compared to the high Fe concentration. Under low Fe conditions, P. parvum upregulated 10 proteins including chloroplastic ATP synthase subunit b, D2 protein of PSII, D1 protein of PSII reaction centre, and light harvesting complex II protein, most of which are associated with photosynthetic activities in PSII. The results suggest that the marine alga P. parvum altered the biosynthesis of several photosynthetic proteins in order to cope with low Fe conditions., M. M. Rahman, M. A. Rahman, T. Maki, T. Nishiuchi, T. Asano, H. Hasegawa., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
28. A method of a bicolor fast-Fourier pulse-amplitude modulation chlorophyll fluorometry
- Creator:
- Lysenko, V., Lazár, D., and Varduny, T.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- chlorofyl, chlorophyll, multi-color PAM, chromatic adaptation, greenhouse lighting, dual-wavelength PAM, 2, and 581
- Language:
- Multiple languages
- Description:
- A simple method of a bicolor (multicolor), fast-Fourier, PAM chlorophyll fluorometry has been developed to obtain fluorescence induction curves. Quantum yields of PSII photochemistry were determined with blue and red simultaneously applied pulsed measuring lights for three subsequent 20-min periods of dark-, light-adaptation under actinic light and dark recovery. Measuring lights were cross-combined with blue and red actinic lights and saturation pulses. Coefficients of chromatic divergence were calculated as a ratio of the quantum yields obtained by red measuring light to that obtained by blue measuring light. Adaptation of Ficus benjamina and Hordeum vulgare leaves under blue (but not red) actinic light resulted in the sufficient increase of chromatic divergence. In addition, fraction of active, non(photo)inhibited, PSII centers was shown to be dependent on the color of measuring light. Thus, color of the light sources should be considered when reporting results of parameters evaluated from fluorescence induction curves., V. Lysenko, D. Lazár, T. Varduny., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
29. A modified nonrectangular hyperbola equation for photosynthetic light-response curves of leaves with different nitrogen status
- Creator:
- Xu, J. Z., Yu, Y. M., Peng, S. Z., Yang, S. H., and Liao, L. X.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- fotosyntéza, photosynthesis, leaf nitrogen, modified nonrectangular hyperbola equation, Oryza sativa, photosynthetic light-response curve, SPAD, 2, and 581
- Language:
- Multiple languages
- Description:
- Chlorophyll index and leaf nitrogen status (SPAD value) was incorporated into the nonrectangular hyperbola (NRH) equation for photosynthetic light-response (PLR) curve to establish a modified NRH equation to overcome the parameter variation. Ten PLR curves measured on rice leaves with different SPAD values were collected from pot experiments with different nitrogen (N) dosages. The coefficients of initial slope of the PLR curve and the maximum net photosynthetic rate in NRH equation increased linearly with the increase of leaf SPAD. The modified NRH equation was established by multiplying a linear SPAD-based adjustment factor with the NRH equation. It was sufficient in describing the PLR curves with unified coefficients for rice leaf with different SPAD values. SPAD value, as the indicator of leaf N status, could be used for modification of NRH equation to overcome the shortcoming of large coefficient variations between individual leaves with different N status. The performance of the SPAD-modified NRH equation should be further validated by data collected from different kinds of plants growing under different environments., J. Z. Xu, Y. M. Yu, S. Z. Peng, S. H. Yang, L. X. Liao., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
30. A new suite of twenty-two polymorphic microsatellite loci in the parasitic wasp, Habrobracon hebetor (Hymenoptera: Braconidae): Promising molecular tools for studying the population genetics of several beneficial braconid species
- Creator:
- Gerba, Madougou, Loiseau, Anne, Benoit, Laure, and Gauthier, Nathalie
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, blanokřídlí, lumčíkovití, populační genetika, Hymenoptera, Braconidae, population genetics, Habrobracon hebetor, Bracon spp., biological control, parasitic wasp, microsatellite, gene flow, 2, and 59
- Language:
- English
- Description:
- Combining a biotin-enrichment protocol and 454GS-FLX titanium pyrosequencing technology, we characterised 22 polymorphic microsatellite loci from the parasitic wasp, Habrobracon hebetor (Say) (Hymenoptera: Braconidae), a cosmopolitan species commonly used in biological control against a wide range of both major lepidopterous pests of stored products and field crops in different parts of the world. Three multiplex PCR sets were optimised and characterised across 46 H. hebetor specimens from two samples collected from millet fields in Niger. Two to 11 alleles were found per locus and observed heterozygosity ranged from 0.289 to 0.826. Polymorphism was detected in both samples with a similar level of observed heterozygosity (0.482 vs. 0.502) and number of alleles (4.1 vs. 3.6). Deviation from Hardy-Weinberg equilibrium was detected at the same five loci in both samples and five or seven more loci in each sample but was not associated with heterozygote deficiencies. Even though evidence for linkage disequilibrium was found between a few alleles, these new loci segregated independently. The variability of the 22 loci will enable estimates of genetic diversity and structure patterns, as well as gene flow between H. hebetor populations at different spatial scales. Cross-species amplifications were successful among the six Bracon spp. tested and nine loci will be particularly appropriate for population genetic studies in B. brevicornis., Madougou Garba, Anne Loiseau, Laure Benoit, Nathalie Gauthier., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public