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392. Conspectus of Australian Brachystomellidae (Collembola) with description of new species of Rapoportella and redescription of Cassagnella anomala
- Creator:
- Greenslade, Penelope
- Format:
- print, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- morfologie (biologie), morphology (biology), Austrálie, Australia, Collembola, Brachystomellidae, distribution, key to genera, Rapoportella edwardi sp. n., S-chaetae, cuticular plates, drying climate, conservation values, ecosystem function, 2, and 59
- Language:
- English
- Description:
- As part of a modern review of all Australian Collembola families, a key is provided to the nine genera of Brachystomellidae currently known from Australia, their morphology is compared, their distribution within and outside Australia is noted and the high diversity of genera in southern regions emphasised. Three Australian genera are endemic, five are also found in South America, South Africa and/or New Zealand and one has a cosmopolitan distribution. The distribution, ecology and habitat preferences of Australian genera are compared. Two genera, Cassagnella Najt & Massoud and Rapoportella Ellis & Bellinger, are newly diagnosed and additions to the description of C. anomala Womersley are given. Australian Cassagnella species appear restricted to southern, humid regions and C. anomala possesses some characters that indicate it is adapted to living in habitats that are periodically flooded. A new species, Rapoportella edwardi sp. n. is described in the rarer genus from drier eucalypt forests. The effect of agricultural practices on an introduced species of Brachystomella is noted and its indicator value emphasised. Possible threats to the endemic genera and species are noted., Penelope Greenslade., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
393. Continuation Der Vollständigen Hauss- und Hand-Bibliotec
- Creator:
- Glorez, Andreas
- Publisher:
- In Verlegung Quirini
- Format:
- print, text, regular print, and [1] l., 392 s., obr. příl.
- Type:
- text, volume, staré tisky, atlasy, model:monograph, and TEXT
- Subject:
- Obecná botanika, Staré tisky, botanika, rostliny, vegetace, atlasy botanické, herbář, ilustrace, 581, 2, 12, 094, and UF01
- Language:
- German
- Description:
- Anderer Theil, In welchem gehandelt wird von der Gestalt, Natur, Kraft und Würckung aller Bäume, Kräuter, vierfüssigen, and durch Andream Glorez von Mährn
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
394. Contribution of leaf nitrogen to photosynthetic gas exchange in contrasting rice (Oryza sativa L.) cultivars during the grain-filling period
- Creator:
- Shimoda, S.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- botanika, botany, carbon discrimination, nitrogen supply, photosynthetic CO2 assimilation, stomatal conductance, 2, and 58
- Language:
- Multiple languages
- Description:
- Photosynthetic parameters and leaf carbon isotope composition (δ13C) in contrasting rice genotypes in relation to supplemental nitrogen (N) application and water management during the grain-filling period were compared. The changes in stomatal conductance (gs) and ratio of intercellular to ambient CO2 mole fraction (Ci/Ca) depended on the leaf nitrogen concentration (leaf N) in both ‘Hinohikari’ (temperate japonica genotype) and ‘IR36’ (indica genotype). In ‘Hinohikari’, δ13C reflects photosynthetic gas exchange during the grain-filling period, which is indicated by the significant response of δ13C to leaf N. In contrast, in ‘IR36’ δ13C did not depend on leaf N. This varietal difference in δ13C to leaf N can be attributed to a difference in the timing of leaf senescence. In ‘IR36’, leaf N and photosynthetic parameters decreased more rapidly, indicating earlier senescence and a shorter grain-filling period in comparison with ‘Hinohikari’. The significant increase in shoot dry mass in ‘Hinohikari’ resulting from supplemental N application, compared with nonsignificant effect observed in ‘IR36’, suggests that the timing of senescence in relation to the grainfilling period has a preponderant influence on productivity., S. Shimoda., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
395. Contribution of stem CO2 fixation to whole-plant carbon balance in nonsucculent species
- Creator:
- Ávila, E., Herrera, A., and Tezara, W.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- fotosyntéza, photosynthesis, carbon balance, CO2 reassimilation, green stem, stem net photosynthesis, stem photosynthesis, stem recycling photosynthesis, 2, and 581
- Language:
- Multiple languages
- Description:
- In many plant species that remain leafless part of the year, CO2 fixation occurring in green stems represents an important carbon gain. Traditionally, a distinction has been made between stem photosynthesis and corticular photosynthesis. All stem photosynthesis is, sensu stricto, cortical, since it is carried out largely by the stem cortex. We proposed the following nomenclature: stem net photosynthesis (SNP), which includes net CO2 fixation by stems with stomata in the epidermis and net corticular CO2 fixation in suberized stems, and stem recycling photosynthesis (SRP), which defines CO2 ling in suberized stems. The proposed terms should reflect differences in anatomical and physiological traits. SNP takes place in the chlorenchyma below the epidermis with stomata, where the net CO2 uptake occurs, and it resembles leaf photosynthesis in many characteristics. SRP is found in species where the chlorenchyma is beneath a well-developed stomata-free periderm and where reassimilation of internally respired CO2 occurs. SNP is common in plants from desert ecosystems, rates reaching up to 60% of the leaf photosynthetic rate. SRP has been demonstrated in trees from temperate forests and it offsets partially a carbon loss by respiration of stem nonphotosynthetic tissues. Reassimilation can vary between 7 and 123% of respired CO2, the latter figure implying net CO2 uptake from the atmosphere. Both types of stem photosynthesis contribute positively to the carbon economy of the species, in which they occur; they are advantageous to the plant because they allow the maintenance of physiological activity during stress, an increase of integrated water use efficiency, and they provide the carbon source used in the production of new organs., E. Ávila, A. Herrera, W. Tezara., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
396. Contribution to the biochemical characterization of the silk and structure characterization of the cocoons of the horse chestnut leaf miner Cameraria ohridella (Lepidoptera: Gracillariidae)
- Creator:
- Hněvsová, Veronika, Dalibor Kodrík, and František Weyda
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, entomologie, silk, cocoon, pupal chamber, tissue of leaf mine, Cameraria ohridella, Gracillariidae, protease inhibitor, glycoprotein, electron microscopy, 2, and 59
- Language:
- English
- Description:
- This study of the proteins in the silk of the summer and winter cocoons of the horse chestnut leaf miner Cameraria ohridella revealed they can inhibit protease activity. The inhibitory activity of the summer silk was higher against both the fungal proteinase K and bacterial subtilisin than that of the winter silk. Also, the winter silk was more effective in inhibiting proteinase K than subtilisin. Further, it was demonstrated that some of the silk proteins are glycosylated probably by mannose carbohydrates. An electron microscopy study of the cocoons revealed the presence of silk fibres with different diameters in some pupal chambers. and Veronika Hněvsová, Dalibor Kodrík, František Weyda.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
397. Control of the maximal chlorophyll fluorescence yield by the QB binding site
- Creator:
- Prášil, Ondřej, Kolber, Z. S., and Falkowski, Paul G.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- fotosyntéza, photosynthesis, conformational change, electron transport, photosystem II, thylakoid membrane, 2, and 581
- Language:
- Multiple languages
- Description:
- Differences in maximal yields of chlorophyll variable fluorescence (Fm) induced by single turnover (ST) and multiple turnover (MT) excitation are as great as 40%. Using mutants of Chlamydomonas reinhardtii we investigated potential mechanisms controlling Fm above and beyond the QA redox level. Fm was low when the QB binding site was occupied by PQ and high when the QB binding site was empty or occupied by a PSII herbicide. Furthermore, in mutants with impaired rates of plastoquinol reoxidation, Fm was reached rapidly during MT excitation. In PSII particles with no mobile PQ pool, Fm was virtually identical to that obtained in the presence of PSII herbicides. We have developed a model to account for the variations in maximal fluorescence yields based on the occupancy of the QB binding site. The model predicts that the variations in maximal fluorescence yields are caused by the capacity of secondary electron acceptors to reoxidize QA-., O. Prášil, Z. S. Kolber, P. G. Falkowski., and Obsahuje bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
398. Convergent photoperiodic plasticity in developmental rate in two species of insects with widely different thermal phenotypes
- Creator:
- Kutcherov, Dmitry, Lopatina, Elena B, and Balashov, Sergei
- Format:
- print, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- polokřídlí, brouci, mandelinkovití, fotoperiodismus, teplota, Hemiptera, beetles, Chrysomelidae, photoperiodism, temperature, Pyrrhocoridae, Scantius aegyptius, Coleoptera, Timarcha tenebricosa, body size, development, reaction norm, seasonality, 2, and 59
- Language:
- English
- Description:
- Growth and development rates in many insects are affected by photoperiod, which enables insects to synchronize their life histories with seasonal events, but this aspect of insect photoperiodism remains understudied. Here we use several experimental combinations of constant day length and temperature to determine whether there are quantitative developmental responses to photoperiod in the bug Scantius aegyptius and leaf beetle Timarcha tenebricosa. The thermal ecology of these two species is strikingly different: the former is thermophilic and active throughout summer and the latter is spring-active and avoids the hottest time of the year. In accordance with their contrasting natural thermal environments, S. aegyptius survives better and achieves a larger final body mass at the high experimental temperatures, while T. tenebricosa survives better and is heavier at the low experimental temperatures. Despite this polarity, long-day conditions accelerate larval development relative to a short-day photoperiod in both species, and this developmental response is stronger at low temperatures. Our re-visitation of previous literature in light of the new findings indicates that this similarity in photoperiodic response is superficial and that relatively faster development in midsummer is likely to have a different ecological role in summer- and spring-active species. In the former, it may allow completion of an additional generation during the favourable season, whereas in the latter, this acceleration likely ensures that the larval stage, which is vulnerable to heat, is completed before the onset of hot weather., Dmitry Kutcherov, Elena B. Lopatina, Sergei Balashov., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
399. Cooperative defence of brood in Nicrophorus quadripunctatus (Coleoptera: Silphidae)
- Creator:
- Suzuki, Seizi
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, entomologie, Coleoptera, Silphidae, Nicrophorus quadripunctatus, biparental care, defence of carcass, 2, and 59
- Language:
- English
- Description:
- A positive correlation between the parental effort of a male and female should promote stable biparental care. In order to prevent infanticide male and female burying beetles are said to guard against intruders cooperatively and the presence of a male partner is said to increase the probability of successful defence. However, this hypothesis is supported only by indirect evidence. In this study this hypothesis is tested by direct observation. Whether the intruder was male or female, contests between the same and the opposite sex occurred, although there were few contests between resident females and intruding males. In addition, resident pairs tended to win irrespective of the sex of the intruder, although it is reported that among burying beetles large beetles usually win intra-sexual contests. In the presence of a partner, a small resident can defend a carcass against a large con-sexual intruder. These results suggest that by means of biparental cooperation burying beetles can repel stronger intruders and supports the hypothesis that the threat of infanticide is the primary explanation for extended biparental care in these beetles. and Seizi Suzuki.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
400. Coordinated variation between veins and stomata in cotton and its relationship with water-use efficiency under drought stress
- Creator:
- Lei, Z. Y., Han, J. M., Yi, X. P., Zhang, W. F., and Zhang, Y. L.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- fotosyntéza, photosynthesis, major leaf veins, maximum stomatal conductance, minor leaf veins, stomata size, 2, and 581
- Language:
- Multiple languages
- Description:
- Drought stress causes changes in vein and stomatal density. The objectives of this study were to determine (1) if the changes in vein and stomatal density are coordinated in cotton (Gossypium hirsutum L.) and (2) how these changes affect water-use efficiency (WUE). The results showed significant positive correlations between vein density and stomatal density when cotton was grown under different degrees of drought stress. WUE was significantly positively correlated with the densities of both veins and stomata. Stomatal pore area and stomatal density on the abaxial leaf side, but not the adaxial side, were significantly correlated with WUE, stomatal conductance, leaf net photosynthetic rate, and transpiration rate. In conclusion, coordinated changes in vein and stomatal density improve the WUE of cotton under drought stress. The abaxial leaf side plays a more important role than the adaxial side in WUE and gas exchange., Z. Y. Lei, J. M. Han, X. P. Yi, W. F. Zhang, Y. L. Zhang., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public