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262. The effects of enhanced UV-B radiation on photosynthetic and biochemical activities in super-high-yield hybrid rice Liangyoupeijiu at the reproductive stage
- Creator:
- Yu, G. H., Li, W., Yuan, Z. Y., Cui, H. Y., Lv, C. G., Gao, Z. P., Han, B., Gong, Y. Z., and Chen, G. X.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- botanika, botany, chloroplast ultrastructure, gas exchange, light reaction, photosynthesis, Rubisco, UV-B radiation, 2, and 58
- Language:
- Multiple languages
- Description:
- a1_We investigated the light reactions, CO2 assimilation, but also the chloroplast ultrastructure in the upper three functional leaves (flag, 2nd, and 3rd leaves) of the Chinese super-high-yield hybrid rice (Oryza sativa L.) Liangyoupeijiu (LYPJ) with ultraviolet-B (UV-B) treatment during reproductive development. Photosynthetic parameters showed that the upper 3 functional leaves of LYPJ entered into senescence approximately 15 days after flag leaf emergence (DAE). Leaves in UV-B treatment exhibited greater efficiency in absorbing and utilizing light energy of photosystem II (PSII), characterized by higher chlorophyll (Chl) content and the whole chain electron transport rate (ETR). However, UV-B radiation reduced activities of Ca2+-ATPase and photophosphorylation. The significantly decreased activity of ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) was greatly associated with the decline in photosynthetic efficiency. The net photosynthetic rate (PN) and stomatal conductance (gs) suffered strong reductions before 25 DAE, and afterwards showed no significant difference between control and treatment. UV-B treatment delayed chloroplasts development of flag leaves. Chloroplast membranes later swelled and disintegrated, and more stromal thylakoids were parallel to each other and were arranged in neat rows, which might be responsible for better performance of the primary light reaction. It is likely that accumulation of starch and an increase in the number of lipid droplet and translucent plastoglobuli were results of an inhibition of carbohydrate transport. Our results suggest that long-term exposure to enhanced UV-B radiation was unlikely to have detrimental effects on the absorption flux of photons and the transport of electrons, but it resulted in the decrease of photophosphorylation and Rubisco activation of LYPJ., a2_The extent of the damage to the chloroplast ultrastructure was consistent with the degree of the inhibition of photosynthesis., G. H. Yu ... [et al.]., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
263. The negative effects of clethodim in photosynthesis and gas-exchange status of maize plants are ameliorated by salicylic acid pretreatment
- Creator:
- Radwan, D. E. M. and Soltan, D. M.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- botanika, botany, clethodim herbicide, gas exchange, photosynthesis, pigments, proteins, salicylic acid, 2, and 58
- Language:
- Multiple languages
- Description:
- In this work, the injuries caused by clethodim herbicide application as well as the use of exogenous salicylic acid (SA) as a protective agent against clethodim in Zea mays leaves were examined. Although the target for clethodim is the inhibition of acetyl coenzyme A carboxylase (ACCase) which is the key enzyme for fatty acid biosynthesis, it can indirectly affect the photosynthetic machinery, gaseous exchange and some biochemical parameters. Clethodim application caused chlorosis and yellowing of leaf-tip parts. Higher doses caused browning or reddening of leaves and sometimes dead parts of the leaf margins were observed. The rate of photosynthesis was significantly lowered and the pigments content was highly reduced as a response to clethodim spraying. Moreover, other gas-exchange properties were altered. Furthermore, accumulation of high amounts of carbohydrates, proteins and proline were detected. SA spraying three days prior clethodim application caused partially or totally disappearance of clethodim injuries and kept the leaves similar to those of control. Improved photosynthesis and enhanced pigments content were observed in leaves treated with SA. Other analyzed parameters showed values similar to those of the corresponding control. From the experimental work, an evidenced role of SA working against clethodim effects was suggested and discussed in this paper., D. E. M. Radwan, D. M. Soltan., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
264. The photosynthetic performance of sterile and fertile sporophytes in a natural population of the fern Dryopteris affinis
- Creator:
- Paoli, L. and Landi, M.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- botanika, botany, chlorophyll fluorescence induction, JIP-test, Mediterranean area, performance index, photosynthesis, pteridophytes, 2, and 58
- Language:
- Multiple languages
- Description:
- We studied the photosynthetic performance of sterile and fertile sporophytes in a natural population of the fern Dryopteris affinis growing within a riparian forest (Central Italy) using chlorophyll (Chl) a fluorescence transients, the OJIP phase, where O is for the minimum fluorescence, P is for the peak (the maximum), and J and I are inflections. The “vitality” of the samples was assessed by the maximum quantum yield of primary photochemistry obtained indirectly from the fluorescence data (Fv/Fm); in the same way, the so-called performance index (PIABS) was obtained from fluorescence data. The photosynthetic performance (inferred from PIABS) of D. affinis changed significantly with the seasonal development of the fronds. The highest photosynthetic performance was recorded in the summer, corresponding to the period of spore release. The photosynthetic performance decreased in the winter, down to the minimal values of senescent fronds reached at the end of the seasonal cycle (May-June). On the whole, during the seasonal development, sterile and fertile fronds had a similar photosynthetic behaviour, as inferred from fluorescence data. At the end of spore maturation and dispersal (September-October), the fertile fronds showed somewhat lower photosynthetic performance than the sterile fronds, as revealed by PIABS. Being a long-lived fern, confined to humid and undisturbed sites in the Mediterranean, D. affinis deserves to be further investigated as a potential indicator of ecological continuity in Mediterranean riparian forests., L. Paoli, M. Landi., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
265. Tis: monografie starobylého vymírajícího stromu se zřetelem na poměry českoslovanské
- Creator:
- Chadt-Ševětínský, Jan Evangelista
- Publisher:
- Chadt
- Format:
- print and 40 s. ; 8°
- Type:
- model:monograph and TEXT
- Subject:
- 58, 2, tis, stromy, and Botanika
- Language:
- Czech
- Description:
- Jan Evang. Chadt (Ševětínský), Zvláštní otisk z XI. roč. Českého háje, and Converted from MODS to DC version 1.8 (EE patch 2018/05/24)
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
266. Transgenic tomato plants overexpressing chloroplastic monodehydroascorbate reductase are resistant to salt- and PEG-induced osmotic stress
- Creator:
- Li, F., Wu, Q. Y., Duan, M., Dong, X. C., Li, B., and Meng, Q. W.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- botanika, botany, ascorbate, monodehydroascorbate reductase, osmotic stresses, reactive oxygen species, tomato, 2, and 58
- Language:
- Multiple languages
- Description:
- RNA gel hybridization showed that the expression of monodehydroascorbate reductase (MDHAR) in the wild type (WT) tomato was decreased firstly and then increased under salt- and polyethylene glycol (PEG)-induced osmotic stress, and the maximum level was observed after treatment for 12 h. WT, sense transgenic and antisense transgenic tomato plants were used to analyze the antioxidative ability to cope with osmotic stresses. After salt stress, the fresh mass (FM) and height of sense transgenic lines were greater than those of antisense lines and WT plants. Under salt and PEG treatments, sense transgenic plants showed a lower level of hydrogen peroxide (H2O2) and malondialdehyde (MDA), a higher net photosynthetic rate (PN), and the maximal photochemical efficiency of PSII (Fv/Fm) compared with WT and antisense transgenic plants. Moreover, sense lines maintained higher ascorbate peroxidase (APX) activity than WT and antisense plants under salt- and PEG-induced osmotic stress. These results indicate that chloroplastic MDHAR plays an important role in alleviating photoinhibition of PSII by elevating ascorbate (AsA) level under salt- and PEG-induced osmotic stress., F. Li ... [et al.]., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
267. Třicet a dwa obrazy k prwopočátkům rostlinoslowí
- Creator:
- Jan Svatopluk Presl
- Publisher:
- Knížecí arcibiskupská knihtiskárna
- Format:
- print, text, regular print, and 30 s., 32 obr. příl.
- Type:
- text, volume, atlasy, model:monograph, and TEXT
- Subject:
- Botanika, rostliny, anatomie rostlin, druhy[bot.], botanika, atlasy botanické, 58, 2, and UF01
- Language:
- Czech
- Description:
- [Sv. 2], Část obrazová, Jan Sw. Presl, and Textová část v samostatné knize
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
268. Trichomy - jedna z adaptací suchomilných rostlin
- Creator:
- Mašková, Hana
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Botanika, botanika, fyziologie rostlin, životní prostředí, botany, plant physiology, environment, 2, and 58
- Language:
- Czech
- Description:
- Článek stručně shrnuje základní adaptace xerotermních rostlin. K těm patří i povrchové struktury vzniklé z epidermis. Blíže je v textu pojednáno o krycích chlupech (trichomech), jejich funkci a morfologii. Článek doplňuji fotografie různých typů těchto trichomů., This article briefly summarises essential adaptations of xerothermic species. These include epidermal structures covering plant surface. The plant hairs (trichomes), their function and morphology are described in detail. The text is supplemented with photos of some trichome types., and Hana Mašková.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
269. Tropické lesy ostrova Borneo. 3. Les nejsou jen stromy aneb zajímavé skupiny flóry
- Creator:
- Martin Dančák, Hroneš, Michal, Kobrlová, Lucie, and Radim Hédl
- Format:
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Botanika, botanika, tropické lesy, flóra, botany, tropical forests, flora, Borneo (Velké Sundy : ostrov), Borneo Island (Indonesia), 2, and 58
- Language:
- Czech
- Description:
- Borneo je ostrovem se zajímavou geomorfologií a překvapivě různorodou geologií. Oba faktory se spolu s historickým vývojem určujícím migrace druhů podílely na současné pestrosti bornejské flóry. Pozoruhodné funkční a taxonomické skupiny rostlin najdeme nejen v zapojeném lese, ale také nad horní hranicí lesa, v pobřežních prostředích, podél vodních toků a jinde. V krátkosti jsou představeny vybrané funční skupiny epifyty, epifyly, liány, masožravé rostliny s význačným rodem láčkovka, nezelené rostliny, rheofyty a alpinské rostliny, mezi kterými nalezneme i trávy temeprátních oblastí. Z pozoruhodných taxonomických skupin představujeme zázvory, áronovité, begonie a pěnišníky, které mají na Borneu jedno z center své diverzity., Borneo is an island with conspicuous geomorphology and variable geology. Both factors have contributed, along with historical development determining species migrations, to the present richness of the flora of Borneo. Remarkable functional and taxonomic groups of herbs occur not only in closed forests, but also above the timberline, in coastal and riparian habitats, and elsewhere. Selected functional groups are briefly introduced: epiphytes, epiphylles, rheophytes, carnivorous, achlorophyllous and alpine plants. From conspicuous taxonomic groups, we introduce gingers, aroids, begonias and rhododendrons., and Martin Dančák ... [et al.].
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
270. Tropické lesy ostrova Borneo. 4. Les přece jen tvoří hlavně stromy
- Creator:
- Michal Hroneš, Radim Hédl, and Martin Dančák
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Botanika, botanika, fyziologie rostlin, životní prostředí, botany, plant physiology, environment, Borneo (Velké Sundy : ostrov), Borneo Island (Indonesia), 2, and 58
- Language:
- Czech
- Description:
- Tropické deštné lesy jihovýchodní Asie jsou známé vysokou druhovou i morfologickou diverzitou rostlin a stromy jsou logicky klíčovou složkou tohoto ekosystému. Ostrov Borneo, se svými přibližně 3 000 druhy dřevin, není v tomto ohledu žádnou výjimkou. Determinace druhů je zde právě kvůli vysoké diverzitě mimořádně složitým a komplexním úkolem, který vyžaduje mnohem větší úsilí než při práci v temperátních ekosystémech. Kromě běžných znaků se při určování tropických dřevin využívají i speciální znaky, jako je např. zásek do borky, barva exudátu či charakteristická vůně. Článek v krátkosti představuje jak významné stromové dominanty deštných lesů Bornea, jako jsou dvoukřídláčovité, tak i další čeledi stromů, jejichž zástupci jsou v lesích bohatě zastoupeni. Zajímavý je také výskyt evolučně starých linií, které nesou primitivní znaky krytosemenných rostlin. Tento článek uzavírá čtyřdílný seriál o tropických lesích Bornea., The tropical rain forests of south-east Asia are famous for their tall plant species and morphological diversity, with trees forming a key component of this ecosystem. The island of Borneo with more than 3,000 species of woody plants is no exception. Due to this high diversity, species identification is a very demanding and complex task, especially in comparison with temperate ecosystems. Apart from traditional characteristics, special traits are also useful for identification, e.g. bark slash and the resulting colour of exudate or typical odour. This article concludes the four-part series and presents a brief overview of dominant tree families of the tropical forests of Borneo including Dipterocarpaceae. The remarkable ancient evolutionary lineages are also introduced., and Michal Hroneš, Radim Hédl, Martin Dančák.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public