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1862. Severe water deficit-induced ethylene production decreases photosynthesis and photochemical efficiency in flag leaves of wheat
- Creator:
- Yang, W., Yin, Y., Jiang, W., Peng, D., Yang, D., Cui, Y., and Wang, Z.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- fotosyntéza, ethylen, pšenice, photosynthesis, ethylene, wheat, 1-aminocyclopropane-1-carboxylic acid, chlorophyll fluorescence, net photosynthetic rate, severe water deficit, Triticum aestivum L., 2, and 581
- Language:
- Multiple languages
- Description:
- Wheat (Triticum aestivum L.) cv. Jimai22 was used to evaluate the effect of ethylene evolution rate (EER) and 1-aminocyclopropane-1-carboxylic acid (ACC) and their relations with photosynthesis and photochemical efficiency in plants well-watered (WW) and under a severe water deficit (SWD). SWD caused a noticeable reduction in the grain mass. The marked increases in both EER and the ACC concentration were observed under SWD; it was reversed effectively by exogenous spermidine (Spd) or amino-ethoxyvinylglycine (AVG). Thermal images indicated that SWD increased obviously the temperature of flag leaves, mainly due to the decrease in transpiration rate under SWD. Exogenous Spd or AVG decreased to some extent the temperature of the flag leaves. The strong decline in photosynthetic rate (PN) and stomatal conductance as well as the photodamage of PSII were also observed under SWD after 14 and 21 days after anthesis (DAA). Intercellular CO2 concentration was reduced at 7 DAA, but slightly increased at 14 and 21 DAA under SWD, indicating that the decreased PN at 7 DAA might result from stomatal limitations, while the decline after 14 and 21 DAA might be attributed to nonstomatal limitations. Correlation analysis suggested that EER and ACC showed negative relations to photosynthesis and photochemical efficiency. Data obtained suggested that the effects of SWD were mediated predominantly by the increase in EER and ACC concentration, which greatly decreased the leaf photosynthesis and photochemical efficiency, and, therefore, reduced the grain mass. Application of Spd or AVG reduced the EER and ACC, and thus positively influenced photosynthesis and photochemical efficiency under SWD., W. Yang, Y. Yin, W. Jiang, D. Peng, D. Yang, Y. Cui, Z. Wang., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1863. Sexual differences in spectral sensitivity and wing colouration of 13 species of Japanese Thecline butterflies (Lepidoptera: Lycaenidae)
- Creator:
- Imafuku, Michio
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, zoologie, entomologie, Theclini, Lycaenidae, Lepidoptera, wing colour, spectral reflectance, sexual dimorphism, spectral sensitivity, electroretinography, 2, and 59
- Language:
- English
- Description:
- The correlation between dorsal wing colours and spectral sensitivity of the compound eyes of 13 species of thecline butterflies, consisting of 8 sexually monomorphic and 5 dimorphic species, was investigated. Spectral reflectance of the dorsal surfaces of the wings was measured using a spectrophotometer and spectral sensitivities using electroretinography. All 13 species examined showed a common basic pattern of spectral sensitivity with a primary peak at a wavelength of 440–460 nm. Detailed analyses of the deviations in sensitivity from the basic pattern revealed a correlation in monomorphic species with conspicuous wing hues, especially in males., Michio Imafuku., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1864. Sexual dimorphism in the Drosophila melanogaster (Diptera: Drosophilidae) metabolome increases throughout development
- Creator:
- Ingleby, Fiona C. and Morrow, Edward H.
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, dvoukřídlí, octomilkovití, ontogeneze, sexuální dimorfismus, Diptera, Drosophilidae, ontogeny, sexual dimorphism, Drosophila melanogaster, metabolome, transcriptome, 2, and 59
- Language:
- English
- Description:
- The expression of sexually dimorphic phenotypes from a shared genome between males and females is a longstanding puzzle in evolutionary biology. Increasingly, research has made use of transcriptomic technology to examine the molecular basis of sexual dimorphism through gene expression studies, but even this level of detail misses the metabolic processes that ultimately link gene expression with the whole organism phenotype. We use metabolic profiling in Drosophila melanogaster to complete this missing step, with a view to examining variation in male and female metabolic profiles, or metabolomes, throughout development. We show that the metabolome varies considerably throughout larval, pupal and adult stages. We also find significant sexual dimorphism in the metabolome, although only in pupae and adults, and the extent of dimorphism increases throughout development. We compare this to transcriptomic data from the same population and find that the general pattern of increasing sex differences throughout development is mirrored in RNA expression. We discuss our results in terms of the usefulness of metabolic profiling in linking genotype and phenotype to more fully understand the basis of sexually dimorphic phenotypes., Fiona C. Ingleby, Edward H. Morrow., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1865. Sexual segregation of Echinorhynchus borealis von Linstow, 1901 (Acanthocephala) in the gut of burbot (Lota lota Linnaeus)
- Creator:
- Tuomainen, Arto, Valtonen, E. Tellervo, and Benesh, Daniel P
- Format:
- electronic, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- poměr pohlaví, sex ratio, thorny-headed worms, body size, Echinorhynchidae, Echinorhynchus cinctulus, microhabitat, niche, spatial distribution, 2, and 59
- Language:
- English
- Description:
- Helminths often occupy defined niches in the gut of their definitive hosts. In the dioecious acanthocephalans, adult males and females usually have similar gut distributions, but sexual site segregation has been reported in at least some species. We studied the intestinal distribution of the acanthocephalan Echinorhynchus borealis von Linstow, 1901 (syn. of E. cinctulus Porta, 1905) in its definitive host, burbot (Lota lota Linnaeus). Over 80% of female worms were found in the pyloric caeca, whereas the majority of males were in the anterior two-thirds of the intestine. This difference was relatively consistent between individual fish hosts. Worms from different parts of the gut did not differ in length, so site segregation was not obviously related to worm growth or age. We found proportionally more males in the caeca when a larger fraction of the females were found there, suggesting mating opportunities influence gut distribution. However, this result relied on a single parasite infrapopulation and is thus tentative. We discuss how mating strategies and/or sexual differences in life history might explain why males and females occupy different parts of the burbot gut., Arto Tuomainen, E. Tellervo Valtonen, Daniel P. Benesh., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1866. Seznam rostlin květeny české
- Creator:
- Opiz, Filip Maxmilián
- Publisher:
- Nákladem Českého museum and V kommissí u Fr. Řivnáče
- Format:
- print, text, regular print, and 216 s. ; 19 cm
- Type:
- model:monograph and TEXT
- Subject:
- 581.9, (437.3), (048.8), 581, 2, flóra, flóra--Česko, and Obecná botanika
- Language:
- Czech
- Description:
- sepsal Filip Max. Opiz, Latinské názvosloví, and Converted from MODS 3.5 to DC version 1.8 (EE patch 2015/06/25)
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1867. Sezonnost tropického deštného lesa z ptačí perspektivy
- Creator:
- Zenklová, Tereza
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Biologické vědy, tropické deštné lesy, ptáci, tropical rain forests, birds, 2, and 57/59
- Language:
- Czech
- Description:
- V naší studii se zabýváme zpěvní a hnízdní aktivitou ptáků v tropickém deštném lese Kamerunské hory v západní Africe. Ukázali jsme, že toto na první pohled stálé prostředí vykazuje výraznou sezonalitu v množství srážek ovlivňujících dostupnost potravy. Důsledkem je variabilní sezónní aktivita ptačího společenstva, zejména různých potravních guild. Sezonalita prostředí i ptačího společenstva se mění také s nadmořskou výškou., The aim of our study, conducted in the Republic of Cameroon (Africa), was to examine the singing and breeding activity of birds in a tropical rain forest. We have shown that this otherwise stable environment exhibits a distinct seasonality in rainfall, resulting in seasonal activity of bird communities, especially of various feeding guilds. Seasonality of environment and breeding of bird communities also changed with the altitude (tested on the Mount Cameroon - Mongo ma Ndemi)., Tereza Zenklová a kolektiv autorů., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1868. Short term response of ants to the removal of ground cover in organic olive orchards
- Creator:
- Campos, Mercedes, Fernández, Luisa, Ruano, Francisca, Cotes, Belén, Cárdenas, Manuel, and Castro, Juan
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, entomologie, Hymenoptera, Formicidae, disturbance, biodiversity, soil management, 2, and 59
- Language:
- English
- Description:
- Ants are the most abundant group of soil arthropods in olive groves where they are involved in various trophic relationships of great importance for crops. The system of soil management is one agricultural practice that has a great effect on ants, so the objective of this study was to compare ant populations in organic olive orchards with a ground cover of natural vegetation and others where this natural vegetation is mechanically removed at the beginning of June. Ants were sampled using pitfall traps at 14, 30, 70 and 90 days after the removal of the ground vegetation. Overall, ant biodiversity did not change. However, changes were observed in the abundance of ant species, in particular, in those species that build shallow nests in the soil, both between the rows of trees and under the canopy of olive trees. In contrast, deep nesting species, such as Messor barbarus, were not affected. The response also differed between the various genera: the abundance of Cataglyphis increased, due to there being more of the species C. rosenhaueri, while there was a significant fall in Aphaenogaster, due to the decline in abundance of A. senilis. Thirty days after the removal of vegetation, the response of most of the genera was clearly noticeable, due to the increased activity of workers, and in some cases there were still differences after 90 days. and Mercedes Campos, Luisa Fernández, Francisca Ruano, Belén Cotes, Manuel Cárdenas, Juan Castro.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1869. Short-term effects of extensive fertilization on community composition and carbon uptake in a Pannonian loess grassland
- Creator:
- Czóbel, Sz., Németh, Z., Szirmai, O., Gyuricza, Cs., Tóth, A., Házi, J., Vikár, D., and Penksza, K.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- fotosyntéza, photosynthesis, canopy chamber, in situ experiment, net ecosystem CO2 exchange, nutrient treatment, species composition, 2, and 581
- Language:
- Multiple languages
- Description:
- Among the most extended ecosystems of the temperate zone, the seminatural, dry grasslands constitute a substantial proportion in the Carpathian Basin. The aim of our present study was to investigate the short-term effect of extensive fertilization on the species composition and CO2 exchange of loess grassland at community level. The in situ investigation of the latter parameter have not been yet carried out in Pannonian loess grasslands. Most of the parameters studied showed a considerable interannual variation both in the fertilized and in the control stands. As a result of the treatment, the average species number of the fertilized stand decreased by 22%, which was more significant in the autumn (26%) than in the spring. Diversity values, including Shannon index and species richness, increased by nearly 1.5 times in the year with adequate rainfall compared with the initial values. In general, species richness and the ratio of dicots decreased, while the ratio of therophytes, alien competitors, and C4 plants increased with the addition of fertilizers. Significant carbon sequestration potential was only detected during wet periods in the fertilized grass. The rate of CO2 uptake was found to be nearly five times higher in the fertilized stand and nearly three times higher in the control stand during the wet year compared with the previous, extremely dry year. The CO2 uptake potential of the fertilized grassland exceeded that of the control stand by 12% in the year with high rainfall, while the rate of CO2 exchange dropped by 50% in the dry year in the fertilized stand. Our study reinforced the idea that the decline in species richness was not necessarily followed by the reduction of stand level carbon uptake in a short period due to an insignificant change in ecophysiological functional groups. and S. Z. Czóbel ... [et al.].
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1870. Short-term effects of surface dust: alleviating photoinhibition of cotton under high irradiance in the Tarim Basin
- Creator:
- Li, L. and Mu, G.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- chlorofyl, chlorophyll, chlorophyll a fluorescence, dust retention, electron transport, photosynthetic rate, 2, and 581
- Language:
- Multiple languages
- Description:
- Dust deposition on leaf surfaces can impact the growth and physiological traits of plants. We carried out a field experiment to investigate short-term effects of light surface dust on photosynthesis of cotton in the Tarim Basin using chlorophyll fluorescence and gas-exchange techniques. JIP-test analysis of OJIP curves showed that the total performance index for leaves without dust decreased by 32% at noon compared to the morning value. High irradiance at noon reduced actual quantum yield of PSII and increased nonphotochemical quenching for leaves without dust, showing photoinhibition. It suggested that light surface dust alleviated photoinhibition of cotton to high irradiance on a short-term basis. For the leaves without dust, high irradiance induced photoinhibition not only with respect to the photochemistry reactions but the biochemical pathways of CO2 fixation. Mechanisms such as thermal dissipation and enhanced electron flux to PSI protected the photosynthetic apparatus under high irradiance., L. Li, G. Mu., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public