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
Caulerpa lentillifera is a green algae that distributes worldwide and is cultivated for food. We assessed vegetative propagation of C. lentillifera by measuring the specific growth rate （SGR） and chlorophyll fluores...Caulerpa lentillifera is a green algae that distributes worldwide and is cultivated for food. We assessed vegetative propagation of C. lentillifera by measuring the specific growth rate （SGR） and chlorophyll fluorescence of the green algae cultured at different salinities and nutrient levels. The results indicated that C. lentillifera can survive in salinities ranging from 20 to 50, and can develop at salinities of 30 to 40. The maximum SGR for C. lentillifera occurred at a salinity of 35. Both chlorophyll content and the ratio of variable to maximum fluorescence （F_v/F_m） were also at a maximum at a salinity of 35. Photosynthesis was inhibited in salinities greater than 45 and less than 25. Both the maximum SGR and maximum chlorophyll content were found in algae treated with a concentration of 0.5 mmol/L of NO3-N and 0.1 mmol/L of PO_4-P. The photosynthetic capacity of photosystem Ⅱ （PSⅡ） was inhibited in cultures of C. lentillifera at high nutrient levels. This occurred when NO_3-N concentrations were greater than 1.0 mmol/L and when PO4-P concentrations were at 0.4 mmol/L. As there is strong need for large-scale cultivation of C. lentillifera, these data contribute important information to ensure optimal results.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
A high non-photochemical quenching(NPQ) appeared below the phase transition temperature when Microcystis aeruginosa PCC7806 cells were exposed to saturated light for a short time.This suggested that a component of NPQ...A high non-photochemical quenching(NPQ) appeared below the phase transition temperature when Microcystis aeruginosa PCC7806 cells were exposed to saturated light for a short time.This suggested that a component of NPQ,independent from state transition or photo-inhibition,had been generated in the PSII complex;this was a fast component responding to high intensity light.Glutaraldehyde(GA),commonly used to stabilize membrane protein conformations,resulted in more energy transfer to PSII reaction centers,affecting the energy absorption and dissipation process rather than the transfer process of phycobilisome(PBS).In comparison experiments with and without GA,the rapid light curves(RLCs) and fluorescence induction dynamics of the fast phase showed that excess excitation energy was dissipated by conformational change in the photosynthetic pigment proteins on the thylakoid membrane(PPPTM).Based on deconvolution of NPQ relaxation kinetics,we concluded that the fast quenching component(NPQ f) was closely related to PPPTM conformational change,as it accounted for as much as 39.42% of the total NPQ.We hypothesize therefore,that NPQ f induced by PPPTM conformation is an important adaptation mechanism for Microcystis blooms under high-intensity light during summer and autumn.展开更多
[Objective] The aim of this study is to understand the high yield often photosynthetic mechanism of super hybrid rice P88S/0389.[Method] Chlorophyll and carotenoid contents were measured via the method of Wellburn and...[Objective] The aim of this study is to understand the high yield often photosynthetic mechanism of super hybrid rice P88S/0389.[Method] Chlorophyll and carotenoid contents were measured via the method of Wellburn and Lichtenthaler,and the photosynthetic rate and chlorophyll fluorescence parameters were measured using portable photosynthesis system.Through comparison of above measured indices between P88S/0389 and its parents,the photosynthetic characteristics were obtained.[Result] The pigment content of P88S/0389 lied between their parents,and detailedly was closer to its female parent at earlier growth stage and to its male parent at latter stage,respectively.The Pn,Fv/Fo,Fv/Fm and qP of the flag leaf of P88S/0389 were all higher than those of its parents,while the degradation rates of these parameters were slower than those of its parents.The qN of flag leaf was lower than those of its parents,and the increasing rate of qN of P88S/0389 was also slower than those of its parents,indicating the great heterosis of P88S/0389 to its parents in photosynthetic capacity.The data show that P88S/0389 is endowed with stronger capacities in light energy absorption,transformation and carbon fixation compared to its parents.[Conclusion] The light energy absorbed by hybrid mainly contributes to photochemical reaction,and little for heat dissipation.For ensuring high yield,the rice cultivars selected for production should synchronously possess higher photosynthetic rate and longer high value duration.展开更多
基于豌豆叶色素乙醇溶液在蓝紫色的发光二极管(LED)照射下产生红色荧光,该红色荧光能被Hg2+熄灭的现象,建立一种简便、快速、定性鉴定溶液中Hg2+的新方法,实验证明其他阳离子基本上不产生干扰。该方法可直接从阳离子混合溶液中定性鉴定H...基于豌豆叶色素乙醇溶液在蓝紫色的发光二极管(LED)照射下产生红色荧光,该红色荧光能被Hg2+熄灭的现象,建立一种简便、快速、定性鉴定溶液中Hg2+的新方法,实验证明其他阳离子基本上不产生干扰。该方法可直接从阳离子混合溶液中定性鉴定Hg2+,其检测Hg2+的最低浓度为5×10-4m o l/L,检出限为5μg。展开更多
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 Technology Program of Basic Research of Qingdao(No.12-1-4-8-(2)-jch)
文摘Caulerpa lentillifera is a green algae that distributes worldwide and is cultivated for food. We assessed vegetative propagation of C. lentillifera by measuring the specific growth rate （SGR） and chlorophyll fluorescence of the green algae cultured at different salinities and nutrient levels. The results indicated that C. lentillifera can survive in salinities ranging from 20 to 50, and can develop at salinities of 30 to 40. The maximum SGR for C. lentillifera occurred at a salinity of 35. Both chlorophyll content and the ratio of variable to maximum fluorescence （F_v/F_m） were also at a maximum at a salinity of 35. Photosynthesis was inhibited in salinities greater than 45 and less than 25. Both the maximum SGR and maximum chlorophyll content were found in algae treated with a concentration of 0.5 mmol/L of NO3-N and 0.1 mmol/L of PO_4-P. The photosynthetic capacity of photosystem Ⅱ （PSⅡ） was inhibited in cultures of C. lentillifera at high nutrient levels. This occurred when NO_3-N concentrations were greater than 1.0 mmol/L and when PO4-P concentrations were at 0.4 mmol/L. As there is strong need for large-scale cultivation of C. lentillifera, these data contribute important information to ensure optimal results.
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.
基金supported by the National Basic Research Program of China(Grant No. 2008CB418002)the National Major Programs of Water Body Pollution Control and Remediation (Grant Nos. 2009ZX07104-005 and 2009ZX07106-001)
文摘A high non-photochemical quenching(NPQ) appeared below the phase transition temperature when Microcystis aeruginosa PCC7806 cells were exposed to saturated light for a short time.This suggested that a component of NPQ,independent from state transition or photo-inhibition,had been generated in the PSII complex;this was a fast component responding to high intensity light.Glutaraldehyde(GA),commonly used to stabilize membrane protein conformations,resulted in more energy transfer to PSII reaction centers,affecting the energy absorption and dissipation process rather than the transfer process of phycobilisome(PBS).In comparison experiments with and without GA,the rapid light curves(RLCs) and fluorescence induction dynamics of the fast phase showed that excess excitation energy was dissipated by conformational change in the photosynthetic pigment proteins on the thylakoid membrane(PPPTM).Based on deconvolution of NPQ relaxation kinetics,we concluded that the fast quenching component(NPQ f) was closely related to PPPTM conformational change,as it accounted for as much as 39.42% of the total NPQ.We hypothesize therefore,that NPQ f induced by PPPTM conformation is an important adaptation mechanism for Microcystis blooms under high-intensity light during summer and autumn.
基金Supported by Natural Science Foundation of Hainan Province(80645)~~
文摘[Objective] The aim of this study is to understand the high yield often photosynthetic mechanism of super hybrid rice P88S/0389.[Method] Chlorophyll and carotenoid contents were measured via the method of Wellburn and Lichtenthaler,and the photosynthetic rate and chlorophyll fluorescence parameters were measured using portable photosynthesis system.Through comparison of above measured indices between P88S/0389 and its parents,the photosynthetic characteristics were obtained.[Result] The pigment content of P88S/0389 lied between their parents,and detailedly was closer to its female parent at earlier growth stage and to its male parent at latter stage,respectively.The Pn,Fv/Fo,Fv/Fm and qP of the flag leaf of P88S/0389 were all higher than those of its parents,while the degradation rates of these parameters were slower than those of its parents.The qN of flag leaf was lower than those of its parents,and the increasing rate of qN of P88S/0389 was also slower than those of its parents,indicating the great heterosis of P88S/0389 to its parents in photosynthetic capacity.The data show that P88S/0389 is endowed with stronger capacities in light energy absorption,transformation and carbon fixation compared to its parents.[Conclusion] The light energy absorbed by hybrid mainly contributes to photochemical reaction,and little for heat dissipation.For ensuring high yield,the rice cultivars selected for production should synchronously possess higher photosynthetic rate and longer high value duration.
文摘基于豌豆叶色素乙醇溶液在蓝紫色的发光二极管(LED)照射下产生红色荧光,该红色荧光能被Hg2+熄灭的现象,建立一种简便、快速、定性鉴定溶液中Hg2+的新方法,实验证明其他阳离子基本上不产生干扰。该方法可直接从阳离子混合溶液中定性鉴定Hg2+,其检测Hg2+的最低浓度为5×10-4m o l/L,检出限为5μg。
