For plants growing in parks and along the roadsides of a city, the environmental and seasonal regulation of growth, or photosynthesis, is seldom assessed. The phenology of plants may differ due to varying environments...For plants growing in parks and along the roadsides of a city, the environmental and seasonal regulation of growth, or photosynthesis, is seldom assessed. The phenology of plants may differ due to varying environments, which may result in different growth or adaptability to local environments. Therefore, we explored several assays and optical indicators of photosynthesis and stress in three tree species (Prunus yedoensis Matsum, Zelkova serrata Makino and Acer palmatum Thunb. ) and two herbaceous species (Artemisia princeps Pamp and Taraxacum officinale Weber)growing commonly in three local parks of Changwon city, a large industrial city in Korea. The photochemical reflectance index (PRI), chlorophyll fluorescence, and pigments including chlorophyll and the flavonoids of leaves were monitored over a growing season for two years to evaluate the adaptability of plants to local environments. The values of all measurements exhibited striking seasonal and regional changes. PRI values were closely timed with photosynthetic activity and the pigment formation of leaves, particularly in some tree species. For the tree species, the plants which had the low values of PRI during the active growing season showed low levels of both chlorophyll fluorescence and high level of flavonoid, indicating that these plants were experiencing low photosynthetic activity and the specific needs in growth and development were not sufficiently provided by the local environment. Our results indicate that PRI provided a clear optical indicator of plant adaptability to the local environment and may provide a useful metric of effective growth using remote sensing measurements. Furthermore, the periodic PRI measurement is encouraged to be included in the surveillance program for city plant management.展开更多
A comparative study on the photosynthetic parameters among intergeneric progenies derived from \%Oryza sativa\% L.×\%Sorghum vulgare\% L., its maternal parent Gui 630 and commercial 3\|line hybrid rice Shanyou 63...A comparative study on the photosynthetic parameters among intergeneric progenies derived from \%Oryza sativa\% L.×\%Sorghum vulgare\% L., its maternal parent Gui 630 and commercial 3\|line hybrid rice Shanyou 63 in pot experiment in greenhouse was conducted. The morphological and photosynthetic characters of canopy leaves and chlorophyll fluorescence kinetic parameters including \%F\%\-v/\%F\%\-m, \%F\%\-v/\%F\%\-0, photochemical quenching coefficient and non\|photochemical coefficient of canopy leaves of 3 varieties were measured. The results showed the progeny, Yuanyou 1, derived from an intergeneric cross of rice and sorghum possesses better canopy spatial architecture with thicker, heavier and bigger canopy leaf than its maternal parent Gui 630. Higher photosynthetic rate due to higher chlorophyll content, higher primary energy transformation efficiency, potential of PSII and non\|photochemical quenching coefficient (\%q\%\-E) were also measured in Yuanyou 1. These explain partly why the intergeneric progeny has higher biomass production, and better tolerance to adverse conditions and higher field yields even under stress conditions.展开更多
Chlorophyll fluorescence parameters such as Fv/Fm, NPQ and ΦII (YII) are widely used to estimate the fitness and photosynthetic activity of plant leaves and non-photochemical dissipation of excessive excitation energ...Chlorophyll fluorescence parameters such as Fv/Fm, NPQ and ΦII (YII) are widely used to estimate the fitness and photosynthetic activity of plant leaves and non-photochemical dissipation of excessive excitation energy in photosystem II. The effect of chloroplast movement on these fluorescence parameters reduces the accuracy of estimations of the size of de-excitation processes, but there is no method to calculate correct parameters from altered (fluctuated) parameters. Chloroplast movement was recently identified as the “middle” kinetic component of NPQ. In this paper, we devised a complex but reasonable mathematical method to remove the effect of chloroplast movement on fluorescence parameters, based on our previously reported fluorescence theory. The fraction of “S fluctuation” (designated as σ) was estimated from fluorescence observations and used to calculate the non-fluctuated Fs and F′m. fluorescence yields. From the σ values, the fractional change of light absorbance by a leaf caused by chloroplast movement was estimated at 70% - 100%, which varied according to the experimental conditions and plant species. The effect of photoinhibition on fluorescence parameters was also examined in this paper. The photochemical and non-photochemical de-excitation sizes during photoinhibition (measured by the parameters qPI and qSlow) changed on a single regression line. Using this correlation, qPI and qSlow can be predicted from Fv/Fm, and the non-fluctuated Fm and Fo values can be estimated from the fluctuated F″m and F″o values.展开更多
Dynamic fluorescent materials play a crucial role in secure inks for data encryption;however,they are still plagued by issues such as photodegradation,poor latency,and susceptibility to unauthorized access.Herein,we p...Dynamic fluorescent materials play a crucial role in secure inks for data encryption;however,they are still plagued by issues such as photodegradation,poor latency,and susceptibility to unauthorized access.Herein,we propose a photochemically modulated dynamic fluorescent encryption system based on^(1)O_(2)sensitization of fluorescent composites,comprising a^(1)O_(2)-sensitive fluorophore(F2)and non-emissive polymers.After UV irradiation,in-situ generated^(1)O_(2)from the polymer effectively binds with F2 to form endoperoxides(F2EPO),resulting in a significant redshift in emission,up to 150 nm.The^(1)O_(2)concentration is closely related to the irradiation time,rendering different fluorescent colors in a time-gated fashion.Moreover,the emission of F2EPO can be regulated by polymer chemical structure,molecular weight,and crosslinking density.Relying on these merits,we develop a dynamic data encryption method with various non-emissive polymers as the data storage media,UV light irradiation as the data encoder,and F2 as the data decoder.UV light irradiation of diverse polymer solutions generates^(1)O_(2)at different concentrations,effectively encoding the data,which remains invisible under both UV and natural lights.The addition of F2 to these irradiated polymer solutions produces different redshifted fluorescence,enabling secure data decryption.Attributing to the non-emissive nature of the polymers,time-gated readout fashion,excellent latency of^(1)O_(2),and subtle interactions between^(1)O_(2)and F2,this data encryption is nearly undecipherable.This work offers an advantage data encryption approach beyond the reach of conventional fluorophores.展开更多
文摘For plants growing in parks and along the roadsides of a city, the environmental and seasonal regulation of growth, or photosynthesis, is seldom assessed. The phenology of plants may differ due to varying environments, which may result in different growth or adaptability to local environments. Therefore, we explored several assays and optical indicators of photosynthesis and stress in three tree species (Prunus yedoensis Matsum, Zelkova serrata Makino and Acer palmatum Thunb. ) and two herbaceous species (Artemisia princeps Pamp and Taraxacum officinale Weber)growing commonly in three local parks of Changwon city, a large industrial city in Korea. The photochemical reflectance index (PRI), chlorophyll fluorescence, and pigments including chlorophyll and the flavonoids of leaves were monitored over a growing season for two years to evaluate the adaptability of plants to local environments. The values of all measurements exhibited striking seasonal and regional changes. PRI values were closely timed with photosynthetic activity and the pigment formation of leaves, particularly in some tree species. For the tree species, the plants which had the low values of PRI during the active growing season showed low levels of both chlorophyll fluorescence and high level of flavonoid, indicating that these plants were experiencing low photosynthetic activity and the specific needs in growth and development were not sufficiently provided by the local environment. Our results indicate that PRI provided a clear optical indicator of plant adaptability to the local environment and may provide a useful metric of effective growth using remote sensing measurements. Furthermore, the periodic PRI measurement is encouraged to be included in the surveillance program for city plant management.
文摘A comparative study on the photosynthetic parameters among intergeneric progenies derived from \%Oryza sativa\% L.×\%Sorghum vulgare\% L., its maternal parent Gui 630 and commercial 3\|line hybrid rice Shanyou 63 in pot experiment in greenhouse was conducted. The morphological and photosynthetic characters of canopy leaves and chlorophyll fluorescence kinetic parameters including \%F\%\-v/\%F\%\-m, \%F\%\-v/\%F\%\-0, photochemical quenching coefficient and non\|photochemical coefficient of canopy leaves of 3 varieties were measured. The results showed the progeny, Yuanyou 1, derived from an intergeneric cross of rice and sorghum possesses better canopy spatial architecture with thicker, heavier and bigger canopy leaf than its maternal parent Gui 630. Higher photosynthetic rate due to higher chlorophyll content, higher primary energy transformation efficiency, potential of PSII and non\|photochemical quenching coefficient (\%q\%\-E) were also measured in Yuanyou 1. These explain partly why the intergeneric progeny has higher biomass production, and better tolerance to adverse conditions and higher field yields even under stress conditions.
文摘Chlorophyll fluorescence parameters such as Fv/Fm, NPQ and ΦII (YII) are widely used to estimate the fitness and photosynthetic activity of plant leaves and non-photochemical dissipation of excessive excitation energy in photosystem II. The effect of chloroplast movement on these fluorescence parameters reduces the accuracy of estimations of the size of de-excitation processes, but there is no method to calculate correct parameters from altered (fluctuated) parameters. Chloroplast movement was recently identified as the “middle” kinetic component of NPQ. In this paper, we devised a complex but reasonable mathematical method to remove the effect of chloroplast movement on fluorescence parameters, based on our previously reported fluorescence theory. The fraction of “S fluctuation” (designated as σ) was estimated from fluorescence observations and used to calculate the non-fluctuated Fs and F′m. fluorescence yields. From the σ values, the fractional change of light absorbance by a leaf caused by chloroplast movement was estimated at 70% - 100%, which varied according to the experimental conditions and plant species. The effect of photoinhibition on fluorescence parameters was also examined in this paper. The photochemical and non-photochemical de-excitation sizes during photoinhibition (measured by the parameters qPI and qSlow) changed on a single regression line. Using this correlation, qPI and qSlow can be predicted from Fv/Fm, and the non-fluctuated Fm and Fo values can be estimated from the fluctuated F″m and F″o values.
基金supported by the National Natural Science Foundation of China(22275193 and 52303355)the Natural Science Foundation of Fujian Province(2021J06034)+2 种基金Self-deployment Project Research Program of Haixi Institutes,Chinese Academy of Science,CXZX-2022-GH09(E255KF0101)Fujian Institute of Research on the Structure of Matter,Chinese Academy of Sciences(E055AJ01)the STS Project of Fujian-CAS(Grant No.:2023T3027).
文摘Dynamic fluorescent materials play a crucial role in secure inks for data encryption;however,they are still plagued by issues such as photodegradation,poor latency,and susceptibility to unauthorized access.Herein,we propose a photochemically modulated dynamic fluorescent encryption system based on^(1)O_(2)sensitization of fluorescent composites,comprising a^(1)O_(2)-sensitive fluorophore(F2)and non-emissive polymers.After UV irradiation,in-situ generated^(1)O_(2)from the polymer effectively binds with F2 to form endoperoxides(F2EPO),resulting in a significant redshift in emission,up to 150 nm.The^(1)O_(2)concentration is closely related to the irradiation time,rendering different fluorescent colors in a time-gated fashion.Moreover,the emission of F2EPO can be regulated by polymer chemical structure,molecular weight,and crosslinking density.Relying on these merits,we develop a dynamic data encryption method with various non-emissive polymers as the data storage media,UV light irradiation as the data encoder,and F2 as the data decoder.UV light irradiation of diverse polymer solutions generates^(1)O_(2)at different concentrations,effectively encoding the data,which remains invisible under both UV and natural lights.The addition of F2 to these irradiated polymer solutions produces different redshifted fluorescence,enabling secure data decryption.Attributing to the non-emissive nature of the polymers,time-gated readout fashion,excellent latency of^(1)O_(2),and subtle interactions between^(1)O_(2)and F2,this data encryption is nearly undecipherable.This work offers an advantage data encryption approach beyond the reach of conventional fluorophores.
