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1452. Ovaries of Puto superbus and Ceroputo pilosellae (Hemiptera: Coccoidea): morphology, ultrastructure, phylogenetic and taxonomic implications
- Creator:
- Michalik, Anna, Kalandyk-Kolodziejczyk, Malgorzata, Simon, Ewa, Kobialka, Michal, and Szklarzewicz, Teresa
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, zoologie, entomologie, Hemiptera, Coccoidea, Puto superbus, Ceroputo pilosellae, ovariole, germ cells, trophocyte, oocyte, scale insects, 2, and 59
- Language:
- English
- Description:
- Ovaries of Puto superbus and Ceroputo pilosellae are composed of numerous short telotrophic ovarioles that are arranged around the distal part of the lateral oviduct. An individual ovariole consists of a distal trophic chamber (= tropharium) and proximal vitellarium. The tropharia enclose individual trophocytes (= nurse cells) and early previtellogenic oocytes termed arrested oocytes. A single oocyte develops in each vitellarium. Analysis of serial sections has shown that ovarioles of P. superbus contain from 16 to 51 germ cells (13–43 trophocytes, 2–7 arrested oocytes, 1 developing oocyte) while those of C. pilosellae from only 8 to 10 germ cells (5–7 trophocytes, 0–2 arrested oocytes, 1 developing oocyte). The classification and phylogeny of scale insects are discussed taking into consideration the results of this study., Anna Michalik ... [et al.]., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1453. Overexpression of calmodulin gene fragment from Antarctic notothenioid fish improves chilling tolerance in Nicotiana benthamiana
- Creator:
- Zhang, T. J., Pan, L. J., Huang, Qingrong, Zhu, L. H., Yang, N., Peng, C. L., and Chen, L. B.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- obecná botanika, general botany, calcium-binding protein, chilling stress, chlorophyll fluorescence, electrolyte leakage, 2, and 581
- Language:
- Multiple languages
- Description:
- Calmodulin (CaM) is a highly conserved calcium sensor protein associated with chilling tolerance in living organisms. It has four EF-hand domains for binding of four Ca2+, two of them located in the N-terminus, and the other two in the C-terminus. A notothenioid CaM gene fragment (CaMm), which only codes for N-terminus of CaM (with two EF-hand domains), was introduced into Nicotiana benthamiana. Effects of its overexpression on chilling tolerance in plants were explored. During 4◦C or 0◦C chilling treatment, both CaMm and CaM transgenic plants showed higher PSII maximum quantum yield, actual quantum yield, and soluble protein content, lower electrolyte leakage and malondialdehyde content than that of the control. The changes in these physiological indices were comparable between the CaMm and CaM transgenic plants during the treatments. These results indicate that the N-terminus of calmodulin is likely the key functional domain involved in the adaptive response to cold stress., T. J. Zhang, L. J. Pan, Q. Huang, L. H. Zhu, N. Yang, C. L. Peng, L. B. Chen., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1454. Overexpression of maize phosphoenolpyruvate carboxylase improves drought tolerance in rice by stabilization the function and structure of thylakoid membrane
- Creator:
- Shen, W. J., Chen, G. X., Xu, J. G., Jiang, Y., Liu, L., Gao, Z. P., Ma, J., Chen, X., Chen, T. H., and Lv, C. F.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- fotosyntéza, photosynthesis, drought stress, phosphoenolpyruvate carboxylase, transgenic rice, oxidative stress, 2, and 581
- Language:
- Multiple languages
- Description:
- Drought impacts severely crop photosynthesis and productivity. Development of transgenic rice overexpressing maize phosphoenolpyruvate carboxylase (PEPC) is a promising strategy for improving crop production under drought stress. However, the molecular mechanisms of protection from PEPC are not yet clear. The objective of this study was: first, to characterize the response of individual photosynthetic components to drought stress; second, to study the physiological and molecular mechanisms underlying the drought tolerance of transgenic rice (cv. Kitaake) over-expressing maize PEPC. Our results showed that PEPC overexpressing improved the ability of transgenic rice to conserve water and pigments during drying as compared to wild type. Despite the fact that drought induced reactive oxygen species and damaged photosystems (especially, PSI) in both lines, higher intercellular CO2 concentration protected the photosynthetic complexes, peptides, and also ultrastructure of thylakoid membranes against the oxidative damage in transgenic rice. In conclusion, although photosynthetic apparatus suffered an inevitable and asymmetric impairment during drought conditions, PEPC effectively alleviated the oxidative damage on photosystems and enhanced the drought tolerance by increasing intercellular CO2 concentration. Our investigation provided critical clues for exploring the feasibility of using C4 photosynthesis to increase the yield of rice under the aggravated global warming., W. J. Shen, G. X. Chen, J. G. Xu, Y. Jiang, L. Liu, Z. P. Gao, J. Ma, X. Chen, T. H. Chen, and C. F. Lv., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1455. Ozone sensitivity of four Pakchoi cultivars with different leaf colors: physiological and biochemical mechanisms
- Creator:
- Zhang, L., Xiao, S., Chen, Y. J., Xu, H., Li, Y. G., Zhang, Y. W., and Luan, F. S.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- fluorescence chlorofylu a, výměna plynu, fotoinhibice, citlivost na ozón, chlorophyll a fluorescence, gas exchange, photoinhibition, ozone sensitivity, Pakchoi cultivars, 2, and 581
- Language:
- Multiple languages
- Description:
- Ozone (O3) is important air pollutant inducing severe losses of horticultural production. Cultivars of the same species, but with different leaf colors, may differ in their ozone sensitivity. However, it has not been clarified yet if different leaf coloration influences such a sensitivity. In this study, two purple-leafed and two green-leafed cultivars of Pakchoi were selected for ozone fumigation (240 ± 20 nmol mol-1, 09:00-16:00 h). Elevated O₃ decreased chlorophyll content, increased anthocyanin (Ant) content, damaged cell membrane integrity, enhanced antioxidative enzyme activities, depressed photosynthetic rate (PN) and stomatal conductance (gs), inhibited maximal quantum yield (Fv/Fm) and effective quantum yield [YII] of PSII photochemistry, and caused visible injury. Purple-leafed cultivars with higher Ant contents were more tolerant than green-leafed cultivars as indicated by lower relative enhancement in malondialdehyde content and lower relative losses in PN, gs, Fv/Fm, and YII. The higher ability to synthesize Ant in the purple-leafed cultivars contributed to their higher photoprotective ability., L. Zhang, S. Xiao, Y. J. Chen, H. Xu, Y. G. Li, Y. W. Zhang, F. S. Luan., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1456. P. Kučera (ed.), M. Stránský, M. Weber, A. Salašová, B. Šarapatka a kolektiv: Úmluva o krajině: důsledky a rizika nedodržování Evropské úmluvy o krajině
- Creator:
- Pavel Kovář
- Format:
- print, bez média, and svazek
- Type:
- article, text, recenze, recensions, model:article, and TEXT
- Subject:
- Biologické vědy, 2, and 57/59
- Language:
- Czech
- Description:
- [autor recenze] Pavel Kovář.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1457. Paclobutrazol-induced alleviation of water-deficit damage in relation to photosynthetic characteristics and expression of stress markers in contrasting wheat genotypes
- Creator:
- Dwivedi, S. K., Arora, Ajay, and Kumar, S.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- fotosyntéza, photosynthesis, oblast listu, prolin, poškození nedostatkem vody, genotypy pšenice, leaf area, proline, water-deficit damage, wheat genotypes, 2, and 581
- Language:
- Multiple languages
- Description:
- Our experiment was conducted in order to find out effects of paclobutrazol (PBZ; 30 μl l-1) on morphology, photosynthetic process, and stress markers under water surplus and deficit conditions in several wheat genotypes. Study revealed that relative water content (RWC), photosynthetic rate, and maximal quantum yield of PSII (FV/FM) was improved after a PBZ application both under irrigation and water deficit across the genotypes, while the stomatal conductance was reduced. Further, the application of PBZ led to reduced leaf area in wheat genotypes. Moreover, a proline content was higher in the wheat genotypes under water stress as compared to the irrigated plants. The application of PBZ led to downregulation of the proline content under water deficit, while there was no significant change in the content and activity under irrigation with or without the PBZ treatment. These findings indicated that due to the application of PBZ the wheat genotypes might sense a lower stress level (indicated by the proline content) and better drought tolerance (according to RWC and photosynthetic characteristics)., S. K. Dwivedi, Ajay Arora, S. Kumar., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1458. Paleogenetika člověka - způsobí analýza archaické DNA revoluci v pohledu na lidskou evoluci?
- Creator:
- Miloš Macholán
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, zoologie, molekulární biologie, virologie, imunologie, fyziologie, genetika, antropologie, molecular biology, virology, immunology, physiology, genetics, anthropology, 2, and 59
- Language:
- Czech
- Description:
- Molekulární genetika vstoupila na antropologické kolbiště koncem 60. let, ale teprve přímá analýza archaické DNA (aDNA) z fosilních pozůstatků od 80. let umožnila přesnější vhled do evoluce našeho druhu ve středním a mladém pleistocénu. Navzdory různým „Jurským parkům“ totiž DNA po smrti organismu rychle degraduje a časové okno její možné analýzy je poměrně omezené. Navíc jsou vzorky kontaminovány DNA okolních organismů. Nicméně velice záhy se pozornost paleogenetiků soustředila na naše příbuzné - neandertálce. Analýza jejich genomu ukázala, že ~2 % jejich DNA se vyskytuje v genomu anatomicky moderního člověka s výjimkou subsaharské Afriky a celkový rozsah tohoto přenosu může dosahovat až 20 %. Křížení s neandertálci lidem zřejmě umožnilo snadnější adaptaci na chladnější podmínky eurasijského kontinentu, současně však přineslo i výskyt některých chorob. Překvapení přinesla sekvence aDNA izolovaná z článku prstu nalezeného v Denisově jeskyni na Altaji. Ukázalo se, že tento jedinec patřil k neznámému druhu odlišnému jak od moderních lidí, tak i od neandertálců. I tito hominini přispěli až 6 % svojí DNA do genomu některých současných populací člověka (JV Asie, Oceánie). Podle nejnovějších poznatků byl tok genů mezi homininy středního a mladého paleolitu poměrně složitý, byla např. detekována příměs neandertálské DNA v genomu denisovců, kteří navíc získali další sekvence od dalšího, blíže neurčeného druhu hominina. Posledním příspěvkem paleogenetiky do obrazu naší evoluce je sekvence mitochondriální DNA získaná ze zhruba 400 tisíc let starých fosilních pozůstatků heidelberského člověka (Homo heidelbergensis) ze Sima de los Huesos (Šachty kostí) z krasové oblasti Atapuerca ve Španělsku, která ukazuje na příbuznost tohoto druhu., Molecular genetics entered the arena of anthropology at the end of the 1960s, but only direct analysis of ancient DNA (aDNA) from fossils since the 80s has permitted a better insight into the evolution of our own species. Despite the rapid decomposition of DNA starting immediately after death, molecular geneticists are now able to retrieve and sequence aDNA tens or even hundreds of thousands years old. Paleogenetic studies of ancient humans and their relatives have revealed a rather complex picture of Middle and Upper Pleistocene hominins (Neanderthals, Denisovans, ante-Neanderthals etc.) and gene flow among them. New and exciting findings changing our views of the evolution of our own species are appearing with an accelerating pace., Miloš Macholán., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1459. Pampeliška koksaghyz - alternativa ke kaučukovníku
- Creator:
- Tomáš Černý
- Format:
- Type:
- article, články, model:article, and TEXT
- Subject:
- Botanika, hvězdnicovité, kaučuk, 2, and 58
- Language:
- Czech
- Description:
- Natural rubber is currently produced largely from the tropical Rubber Tree (Hevea brasiliensis), which is grown on large plantations in south-eastern Asia. However, some rubber-forming plants can also be found in the temperate zone. The most important species is the tiny dandelion named Koksaghyz or the Russian Dandelion (Taraxacum koksaghyz), belonging to the Asteraceae family and native to south-eastern Kazakhstan. This plant has an exciting history and recently has been intensively researched as an alternative to Hevea rubber. This article describes value of this member of Asteraceae family for the human community. and Tomáš Černý.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1460. Paovce hřivnatá - příběh s dobrým koncem
- Creator:
- Miloš Anděra and Václavová, Lenka
- Format:
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, ovce, 2, and 59
- Language:
- Czech
- Description:
- This article summarizes available data on the free-living population of the Barbary Sheep (Ammotragus lervia) in the Plzeň District in the 1970s to 1990s. This population originated through repeated escapes of the Barbary Sheep from the Plzeň Zoo (1972–87). The Barbary Sheep appeared to be viable in the wild, and its free-living population ceased to exist not before 1994. Additionally, a short review of the Barbary Sheep stock in Czech zoos is presented (1985–2011). and Miloš Anděra, Lenka Václavová.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public