Provider: Czech digital library/Česká digitální knihovna - Institution: Academy of Sciences Library/Knihovna Akademie věd ČR - Data provided by Europeana Collections- Antonina A. Ovchinnikova, Andrey ...N. Ovchinnikov, Margarita Yu. Dolgovskaya, Sergey Ya. Reznik, Natalia A. Belyakova.- Obsahuje bibliografii- Ovipositing females from invasive (Krasnodar Territory of Russia) and native (Far East of Russia) populations of Harmonia axyridis were fed one of a set of diets ranging from 50 Myzus persicae aphids every day to 1 aphid every 10 days and all were also provided with a 10% sugar solution. The experiment was conducted at 20°C under short (12 h) and long (18 h) day conditions. Most of the females from the native population that consumed 50 or 10 aphids per day continued to oviposit under both long and short day conditions. Females that consumed 1 aphid per day or every 2 days practically stopped laying eggs but under long day conditions their ovaries were still active, whereas under short day conditions ca 50% of them were reproductively inactive (only germaria present) and had a well-developed fat body. Further reduction in diet resulted in an increase in the proportion of reproductively inactive females. However, about half of the females that terminated oogenesis under long day conditions had poorly developed fat bodies, which indicates that diapause was not induced. For the females from the invasive population, both photoperiodic and trophic effects were weak: under short day conditions, some females entered diapause when prey was abundant, whereas about 50% (independent of photoperiod) did not enter diapause when starved. This risk-spreading strategy, possibly, facilitates the adaptation of this invasive ladybird to unpredictable environmental conditions.- All metadata published by Europeana are available free of restriction under the Creative Commons CC0 1.0 Universal Public Domain Dedication. However, Europeana requests that you actively acknowledge and give attribution to all metadata sources including Europeana
Provider: Czech digital library/Česká digitální knihovna - Institution: Academy of Sciences Library/Knihovna Akademie věd ČR - Data provided by Europeana Collections- Sergey Ya. Reznik, Antonina A. ...Ovchinnikova, Andrey N. Ovchinnikov, Larisa V. Barabanova, Natalia A. Belyakova.- Obsahuje bibliografii- It is known that females from native populations of the multicoloured Asian ladybird, Harmonia axyridis, have a strong photoperiodic response (enter reproductive diapause under short photoperiods), whereas the proportion of diapausing females from invasive populations is less dependent on day length. The aim of the present study was to determine the mode of inheritance of these differences. The experiments were conducted with two laboratory populations of H. axyridis, the High Diapause (HD) population originated from Irkutsk (Southern Siberia, ca 52.3°N, 104.3°E) and the Low Diapause (LD) population originated from Sochi (North Caucasus, ca 43.6°N, 39.6°E). Reciprocal first generation hybrids and reciprocal backcrosses were investigated. Under a strong diapause-inducing photoperiod (12 h) 100% of the females from the HD population and about 70% of those from the LD population entered diapause. First generation hybrids, as well as their backcrosses with individuals from the HD population, showed almost 100% diapause. Among the backcrosses with the LD population the percentage of diapausing females was widely variable (70-100%) but close to the average between the two populations. The comparison of reciprocal crosses did not reveal any significant difference. We conclude that photoperiodic induction of diapause in the populations of H. axyridis studied is most probably determined by several genes (although one of them evidently plays a leading role with diapause being dominant over non-diapause) and that male and female genotypes are equally important in the determination of female reproductive diapause.- All metadata published by Europeana are available free of restriction under the Creative Commons CC0 1.0 Universal Public Domain Dedication. However, Europeana requests that you actively acknowledge and give attribution to all metadata sources including Europeana
The combined structural study of proteins and of their corresponding genes utilizing the methods of both protein and nucleotide chemistry greatly accelerates and considerably simplifies both the ...nucleotide and protein structure determination and, in particular, enhances the reliability of the analysis. This approach has been successfully applied in the primary structure determination of the β and β′ subunits of Escherichia coli DNAdependent RNA polymerise and of their structural genes, yielding a continuous nucleotide, sequence (4714 base pairs) that embraces the entire rpoB gene, the initial part of the rpoC gene and the intercistronic region, together with the total amino acid sequence of the β subunit, comprising 1342 residues, and the N‐terminal sequence of the β′ subunit (176 residues).
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