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312. Chlorophyll a fluorescence analysis of high-yield rice (Oryza sativa L.) LYPJ during leaf senescence
- Creator:
- Wang, Y. W., Xu, C., Lv, C. F., Wu, M., Cai, X. J., Liu, Z. T., Song, X. M., Chen, G. X., and Lv, C. G.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- fotosyntéza, photosynthesis, thylakoid membrane, JIP-test, natural senescence, PSII efficiency, 2, and 581
- Language:
- Multiple languages
- Description:
- Photosystem II (PSII) photochemistry was examined by chlorophyll (Chl) a fluorescence analysis in high-yield rice LYPJ flag leaves during senescence. Parameters deduced from the JIP-test showed that inhibition of the donor side of PSII was greater than that of the acceptor side in hybrid rice LYPJ. The natural senescence process was accompanied by the increased inactivation of oxygen-evolving complex (OEC) and a lower total number of active reaction centers per absorption. It indicated that the inhibition of electron transport caused by natural senescence might be caused partly by uncoupling of the OEC and/or inactivation of PSII reaction centers. Chl fluorescence parameters analyzed in this study suggested that energy dissipation was enhanced in order to protect senescent leaves from photodamage. Nevertheless, considerably reduced PSI electron transport activity was observed at the later senescence. Thus, natural senescence inhibited OEC-PSII electron transport, but also significantly limited the PSII-PSI electron flow., Y. W. Wang, C. Xu, C. F. Lv, M. Wu, X. J. Cai, Z. T. Liu, X. M. Song, G. X. Chen, C. G. Lv., and Seznam literaruty
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
313. Chlorophyll a fluorescence as a tool for a study of the Potato virus Y effects on photosynthesis of nontransgenic and transgenic Pssu-ipt tobacco
- Creator:
- Spoustová, P., Synková, Helena, Valcke, R., and Čeřovská, N.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- botanika, botany, chlorophyll a fluorescence imaging, cytokinins, gas-exchange parameters, ipt, photosynthesis, Potato virus Y, transgenic tobacco, 2, and 58
- Language:
- Multiple languages
- Description:
- The effect of Potato virus Y NTN (PVY) infection upon photosynthesis was analysed in transgenic Pssu-ipt tobacco overproducing endogenous cytokinins in comparison with control, nontransgenic Nicotiana tabacum plants. The course of the infection from the early to the late stage was monitored by measuring of photosynthetic gas exchange and fast chlorophyll (Chl) a fluorescence induction kinetics. Leaf photosynthesis was also analysed using Chl fluorescence imaging (Chl-FI). From the different fluorescence parameters obtained using Chl-FI, the nonphotochemical quenching (NPQ) proved to be the most useful parameter to assess the effect of PVY infection. On the other hand, Chl-FI was found to be inapplicable for any presymptomatic detection of PVY infection in tobacco. The lower accumulation of the virus was found in transgenic plants and corresponded also with the presence of visible symptoms of PVY infection. The net photosynthetic rate (PN), transpiration rate (E), and stomatal conductance (gs) significantly decreased with the progress of the infection in both control plant types and transgenic rooted plants, while transgenic grafts were much less affected. The analysis of the Chl fluorescence transient revealed higher number of silent dissipative reaction centres, higher nonphotochemical dissipation, and significantly lower performance index, PI(abs), in the healthy transgenic grafts. Chl-FI also confirmed significantly higher NPQ in transgenic grafts., P. Spoustová ... [et al.]., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
314. Chlorophyll a fluorescence of typical desert plant Alhagi sparsifolia Shap. at two light levels
- Creator:
- Li, L., Li, X. Y., Zeng, F. J., and Lin, L. S.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- fotosyntéza, photosynthesis, shade, quantum yield, diurnal changes, electron transport chain, photosystem II activity, 2, and 581
- Language:
- Multiple languages
- Description:
- Alhagi sparsifolia Shap. is exposed to a high-irradiance environment as the main vegetation found in the forelands of the Taklamakan Desert. We investigated chlorophyll a fluorescence emission of A. sparsifolia seedlings grown under ambient (HL) and shade (LL) conditions. Our results indicated that the fluorescence intensity in the leaves was significantly higher for LL-grown plants than that under HL. High values of the maximum quantum yield of PSII for primary photochemistry (φPo) and the quantum yield that an electron moves further than QA - (φEo) in the plants under LL conditions suggested that the electron flow from QA - (primary quinone electron acceptors of PSII) to QB (secondary quinone acceptor of PSII) or QB - was enhanced at LL compared to natural HL conditions. The efficiency/probability with which an electron from the intersystem electron carriers was transferred to reduce end electron acceptors at the PSI acceptor side and the quantum yield for the reduction of end electron acceptors at the PSI acceptor side were opposite to φPo, and φEo. Thus, we concluded that the electron transport on the donor side of PSII was blocked under LL conditions, while acceptor side was inhibited at the HL conditions. The PSII activity of electron transport in the plants grown in shade was enhanced, while the energy transport from PSII to PSI was blocked compared to the plants grown at HL conditions. Furthermore, PSII activity under HL was seriously affected in midday, while the plants grown in shade enhanced their energy transport., L. Li, X. Y. Li, F. J. Zeng, L. S. Lin., and Seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
315. Chlorophyll content and photosystem II efficiency in soybean exposed to supplemental ultraviolet-B radiation
- Creator:
- Hu, Z., Li, H., Chen, S., and Yang, Y.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- botanika, botany, chlorophyll content, fluorescence quenching, Glycine max, rapid light curves, ultraviolet-B radiation, 2, and 58
- Language:
- Multiple languages
- Description:
- Chlorophyll (Chl) a fluorescence parameters and rapid light curves of soybean [Glycine max (L.) Merrill] were measured by pulse amplitude modulation fluorometry. Measurements were taken during different stages of soybean growth under field conditions with 20% enhancement in ultraviolet-B (UV-B) radiation. Results showed that supplemental UV-B radiation decreased Chl contents by 5.5% (P=0.048), 8.7% (P=0.046), and 10.5% (P=0.005) in seedling, in branching-flowering, and in pod-setting stages, respectively. In the branching-flowering and pod-setting stages, maximum quantum yield of photosystem (PS) II photochemistry (Fv/Fm) decreased by 6.1% (P=0.001) and 3.0% (P=0.009), respectively. Supplemental UV-B radiation significantly decreased the effective quantum yield (Y). The photosynthetic capacity at light saturation (Pm) also decreased in both the seedling and branching-flowering stages by 28.9% (P=0.007) and 15.5% (P=0.041), respectively. However, Y and Pm showed no significant difference in the trefoil and pod-setting stages with and without the UV treatment. The light saturation parameter (E k) decreased by 21.1% (P=0.000) and 23.2% (P=0.029) in the trefoil and seedling stages, respectively. Moreover, the initial slope (α) decreased by 21.1% (P=0.001) in the branching-flowering stage. Nonphotochemical quenching (NPQ) in the seedling stage and photochemical quenching coefficient (qp) in the branching-flowering stage decreased significantly under UV-B treatments. The results of the present study suggest that supplemental UV-B radiation adversely affected Chl content and electron transport activity in PSII and consequently decreased the photosynthetic efficiency of soybean plants., Z. Hu ... [et al.]., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
316. Chlorophyll fluorescence and gas exchange measurements in field research: an ecological case study
- Creator:
- Bucher, S. F., Bernhardt-Römermann, M., and Römermann, C.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- chlorofyl, fluorescence, chlorophyll, Aposeris foetida, carbon isotope discrimination, Knautia dipsacifolia, leaf nitrogen, Mercurialis perennis, Trifolium pratense, 2, and 581
- Language:
- Multiple languages
- Description:
- We tested whether cheap and quick chlorophyll (Chl) fluorescence can be used in ecophysiological field studies as proxies for gas-exchange measurements. We measured net photosynthetic rate at saturating irradiance and ambient atmospheric CO2 concentrations (PNsat), maximum carboxylation rate (Vcmax), maximum quantum yield of PSII (Fv/Fm), the performance index (PIabs), leaf nitrogen (Narea), and carbon isotope discrimination (Δ13C) within four herbaceous species along two elevational gradients. We analysed the relationship between Chl fluorescence and gas-exchange parameters and their link to indirect assessment of plant performance via ecophysiological traits. Fv/Fm showed no relationship to PNsat and only weak relationships to Vcmax. PIabs was positively related to PNsat and Vcmax. PIabs, PNsat, and Vcmax were positively associated with Narea and negatively to Δ13C, whereas Fv/Fm showed no relationship to Narea and a positive to Δ13C. Thus, PIabs might be suitable to characterize the photosynthetic activity when aiming on large numbers of samples., S. F. Bucher, M. Bernhardt-Römermann, C. Römermann., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
317. Chlorophyll fluorescence characteristics and the growth response of Elaeocarpus glabripetalus to simulated acid rain
- Creator:
- Liu, M. H., Yi, L. T., Yu, S. Q., Yu, F., and Yin, X. M.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- fotosyntéza, kyselé deště, photosynthesis, acid rain, Čína, China, acid stress, growth adaptability, photosynthetic efficiency, Elaeocarpus glabripetalus, 2, and 581
- Language:
- Multiple languages
- Description:
- Acid rain causes damages to forest ecosystems. Here, we reported that acid rain could promote plant growth. From 2006 to 2009, one-year-old Elaeocarpus glabripetalus seedlings were sprayed with simulated acid rain (AR) (pH 2.5, 4.0, and 5.6). The maximum quantum yield efficiency of PSII and the actual photochemical quantum efficiency of PSII increased with rising AR acidity, which facilitated chlorophyll fluorescence and plant growth, as shown by a declining minimal fluorescence yield of dark-adapted state with little damage to the PSII reaction center. After the second experimental year, the plant height and ground diameter were greater at pH 2.5 than those found at pH 4.0 and 5.6. This showed the positive effects of AR on the seedling growth and photosynthesis of E. glabripetalus, revealing that this species exhibited a stronger resistance to acid deposition than some other tree species. This implies that E. glabripetalus is an acid-tolerant species., M.H. Liu, L.T. Yi, S.Q. Yu, F. Yu, X.M. Yin., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
318. Chlorophyll fluorescence emission spectroscopy of oxygenic organisms at 77 K
- Creator:
- Lamb, J. J., Røkke, G., and Hohmann-Marriott, M. F.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- fluorescence, nízké teploty, fotosyntéza, low temperatures, photosynthesis, 2, and 581
- Language:
- Multiple languages
- Description:
- Photosynthetic fluorescence emission spectra measurement at the temperature of 77 K (-196°C) is an often-used technique in photosynthesis research. At low temperature, biochemical and physiological processes that modulate fluorescence are mostly abolished, and the fluorescence emission of both PSI and PSII become easily distinguishable. Here we briefly review the history of low-temperature chlorophyll fluorescence methods and the characteristics of the acquired emission spectra in oxygen-producing organisms. We discuss the contribution of different photosynthetic complexes and physiological processes to fluorescence emission at 77 K in cyanobacteria, green algae, heterokont algae, and plants. Furthermore, we describe practical aspects for obtaining and presenting 77 K fluorescence spectra., J. J. Lamb, G. Røkke, M. F. Hohmann-Marriott., and Obsahuje bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
319. Chlorophyll fluorescence imaging can reflect development of vascular connection in grafting union in some Solanaceae species
- Creator:
- Penella, C., Pina, A., San Bautista, A., López-Galarza, S., and Calatayud, Á.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- obecná botanika, pepper, callus, compatibility, graft, photochemical quenching, vascular connections, 2, and 581
- Language:
- Multiple languages
- Description:
- Graft union development in plants has been studied mainly by destructive methods such as histological studies. The aim of this work was to evaluate whether the chlorophyll fluorescence imaging (CFI) technique is sensitive enough to reflect changes at the cellular level in different Solanaceae grafted plants 30 d after grafting, when both grafted partners were well fused and strong enough in all plant combinations. The pepper cultivar ‘Adige’ was grafted onto different Capsicum spp. accessions typified with different compatibility degrees; eggplant was grafted on Solanum torvum and pepper homografts as compatible unions; pepper was grafted on S. torvum and on tomato as incompatible unions. ‘Adige’/’Adige’ and ‘Adige’/pepper A25 showed a higher maximum quantum efficiency of PSII associated with higher values of actual quantum efficiency of PSII and photochemical quenching as well as with vascular regeneration across the graft interface. Our results highlighted that CFI changes reflected histological observations in grafted Solanaceae plants., C. Penella, A. Pina, A. San Bautista, S. López-Galarza, Á. Calatayud., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
320. Chlorophyll fluorescence imaging for process optimisation in horticulture and fresh food production
- Creator:
- Herppich, W. B.
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- fyziologie rostlin, plant physiology, internal quality, photosystem II, postharvest research, postharvest processing, 2, and 581
- Language:
- Multiple languages
- Description:
- Chlorophyll a fluorescence analysis (CFA) has been accepted to study postharvest activity and stability of photosynthesis of vegetables and salad greens, and some fruits. Commercial chlorophyll fluorescence imaging (CFI) systems may provide additional insight into spatial and temporal dynamics of photosynthesis. This yields valuable information on the effects of postharvest handling and processing (sorting, cutting, packaging, etc.) on physiological activity and 'internal quality' of green produce, and its changes. Here, meaning and physiological basics of relevant fluorescence parameters is briefly summarised, while major focus is on recent applications of CFI to evaluate quality and quality maintenance during postharvest handling and minimal processing of fresh fruits and vegetables. CFI is given surprisingly little attention in the monitoring of postharvest quality, although it is suitable for adjusting and/or optimising innovative postharvest techniques. Knowledge of the physiological base and the limit of interpretation is indispensable for meaningful interpretations of results to draw correct consequences., W. B. Herppich., and Obsahuje bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public