Spraying 1-2 mmol/L solution of NaHSO 3 on rice ( Oryza sativa L.) leaves resulted in the enhancement of net photosynthetic rate for more than three days. It was also observed that NaHSO 3 application caused incr...Spraying 1-2 mmol/L solution of NaHSO 3 on rice ( Oryza sativa L.) leaves resulted in the enhancement of net photosynthetic rate for more than three days. It was also observed that NaHSO 3 application caused increases both in ATP content in leaves and the millisecond_delayed light emission of leaves. The increase in net photosynthetic rate caused by NaHSO 3 treatment was similar to that by PMS (phenazine methosulfate) treatment. The grain yield of treated rice was enhanced approximately by 10% after duplicated application of NaHSO 3 in milk_ripening stage. It is suggested that the enhancement of photosynthesis by NaHSO 3 treatment resulted from the effect of increasing ATP supplement. Concomitant with an increase in the photosynthetic rate and ATP content in leaves, the transient increase in chlorophyll fluorescence after the termination of actinic light, which could be used as an index of the cyclic electron flow, was also enhanced by low concentration of NaHSO 3 treatment. Basing on these results it is proposed that the increase in rice photosynthesis caused by low concentrations of NaHSO 3 could be due to the stimulation of the cyclic electron flow around PSⅠ which in turn the enhancement of the coupled photophosphorylation and photosynthesis.展开更多
: Spraying a 1–2 mmol/L solution of NaHSO3 on the leaves of wild-type rice (Oryza sativa L.) Kitaake (WT), phosphoenolpyruvate carboxylase (PEPC) transgenic (PC) rice and PEPC+phosphate dikinase (PPDK) transgenic ric...: Spraying a 1–2 mmol/L solution of NaHSO3 on the leaves of wild-type rice (Oryza sativa L.) Kitaake (WT), phosphoenolpyruvate carboxylase (PEPC) transgenic (PC) rice and PEPC+phosphate dikinase (PPDK) transgenic rice (PC+PK), in which the germplasm was transformed with wild-type Kitaake as the gene receptor, resulted in an enhancement of the net photosynthetic rate by 23.0%, 28.8%, and 34.4%, respectively, for more than 3 d. It was also observed that NaHSO3 application caused an increase in the ATP content in leaves. Spraying PMS (a cofactor catalysing the photophosphorylation cycle) and NaHSO3 separately or together on leaves resulted in an increase in photosynthesis with all treatments. There was no additional effect on photosynthetic rate when the mixture was applied, suggesting that the mechanism by which NaHSO3 promotes photosynthesis is similar to the mechanism by which PMS acts and that both of compounds enhanced the supply of ATP. After spraying a solution of NaHSO3 on leaves, compared with the WT Kitaake rice, a greater enhancement of net photosynthetic rate was observed in PEPC transgenic (PC) and PEPC+PPDK transgenic (PC+PK) rice, with the greatest increase being observed in the latter group. Therefore ATP supply may become the limiting factor that concentrates CO2 in rice leaves transformed with an exogenous PEPC gene and exogenous PEPC+PPDK genes.展开更多
Spraying 1-2 mmol/L NaHSO3 on the leaf of wheat results in enhancement of photosynthesis in leaves for about 3 d. The amount of ATP has been increased and the millisecond delayed light emission of the leaves has been ...Spraying 1-2 mmol/L NaHSO3 on the leaf of wheat results in enhancement of photosynthesis in leaves for about 3 d. The amount of ATP has been increased and the millisecond delayed light emission of the leaves has been enhanced, showing that the transmembrane proton motive force related to photophosphorylation is increased. Spraying PMS (a cofactor catalyzing cycle photophosphorylation) and NaHSO3 separately or together on the leaves, 20% increase in photosynthesis has been observed in all the treatments. There is no additive effect when a mixture is applied, suggesting that the mechanism for NaHSO3 promotion of photosynthesis is similar to PMS, and both of them enhance the supply of ATP.展开更多
New and enhanced functions were potentially imparted to the plant organelles after interaction with nanoparticles.In this study,we found that∼44%and∼29%of the accumulated graphene in the rice leaves passively transp...New and enhanced functions were potentially imparted to the plant organelles after interaction with nanoparticles.In this study,we found that∼44%and∼29%of the accumulated graphene in the rice leaves passively transported to the chloroplasts and thylakoid,respectively,significantly enhanced the fluorescence intensity of chloroplasts,and promoted about 2.4 times higher adenosine triphosphate production than that of controls.The enhancement of graphene on the photophosphorylation was ascribed to two reasons:One is that graphene facilitates the electron transfer process of photosystem II in thylakoid,and the other is that graphene protects the photosystem II against photo-bleaching by acting as a scavenger of reactive oxygen species.Overall,our work here confirmed that graphene translocating in the thylakoid promoted the photosynthetic activity of chloroplast in vivo and in vitro,providing new opportunities for designing biomimetic materials to enhance the solar energy conversion systems,especially for repairing or increasing the photosynthesis activity of the plants grown under stress environment.展开更多
Physiological, biochemical and electron microscopy analyses were used to investigate the photosynthetic performance of flag leaves in rice white stripe mutant 6001 during the senescence process. Results showed that th...Physiological, biochemical and electron microscopy analyses were used to investigate the photosynthetic performance of flag leaves in rice white stripe mutant 6001 during the senescence process. Results showed that the chlorophyll content at the heading and milk-ripe stages in rice mutant 6001 were about 34.78% and 3.00% less than those in wild type 6028, respectively. However, the chlorophyll content at the fully-ripe stage in rice mutant 6001 was higher than that in wild type 6028. At the heading stage, the net photosynthetic rate （Pn） in rice mutant 6001 was lower than that in wild type 6028. Rice mutant 6001 also exhibited a significantly slower decrease rate of Pn than wild type 6028 during the senescence progress, especially at the later stage. Furthermore, Ca2^-ATPase, Mg~^-ATPase and photophosphorylation activities exhibited the similar trends as the Po. During the senescence process, the 68 kDa polypeptide concentrations in the thylakoid membrane proteins exhibited a significant change, which was one of the critical factors that contributed to the observed change in photosynthesis. We also observed that the chloroplasts of rice mutant 6001 exhibited higher integrity than those of wild type 6028, and the chloroplast membrane of rice mutant 6001 disintegrated more slow during the senescence process. In general, rice mutant 6001 had a relatively slower senescence rate than wild type 6028, and exhibited anti-senescence properties.展开更多
文摘Spraying 1-2 mmol/L solution of NaHSO 3 on rice ( Oryza sativa L.) leaves resulted in the enhancement of net photosynthetic rate for more than three days. It was also observed that NaHSO 3 application caused increases both in ATP content in leaves and the millisecond_delayed light emission of leaves. The increase in net photosynthetic rate caused by NaHSO 3 treatment was similar to that by PMS (phenazine methosulfate) treatment. The grain yield of treated rice was enhanced approximately by 10% after duplicated application of NaHSO 3 in milk_ripening stage. It is suggested that the enhancement of photosynthesis by NaHSO 3 treatment resulted from the effect of increasing ATP supplement. Concomitant with an increase in the photosynthetic rate and ATP content in leaves, the transient increase in chlorophyll fluorescence after the termination of actinic light, which could be used as an index of the cyclic electron flow, was also enhanced by low concentration of NaHSO 3 treatment. Basing on these results it is proposed that the increase in rice photosynthesis caused by low concentrations of NaHSO 3 could be due to the stimulation of the cyclic electron flow around PSⅠ which in turn the enhancement of the coupled photophosphorylation and photosynthesis.
基金国家自然科学基金，the National Key Project of the International Cooperation for Science and Technology
文摘: Spraying a 1–2 mmol/L solution of NaHSO3 on the leaves of wild-type rice (Oryza sativa L.) Kitaake (WT), phosphoenolpyruvate carboxylase (PEPC) transgenic (PC) rice and PEPC+phosphate dikinase (PPDK) transgenic rice (PC+PK), in which the germplasm was transformed with wild-type Kitaake as the gene receptor, resulted in an enhancement of the net photosynthetic rate by 23.0%, 28.8%, and 34.4%, respectively, for more than 3 d. It was also observed that NaHSO3 application caused an increase in the ATP content in leaves. Spraying PMS (a cofactor catalysing the photophosphorylation cycle) and NaHSO3 separately or together on leaves resulted in an increase in photosynthesis with all treatments. There was no additional effect on photosynthetic rate when the mixture was applied, suggesting that the mechanism by which NaHSO3 promotes photosynthesis is similar to the mechanism by which PMS acts and that both of compounds enhanced the supply of ATP. After spraying a solution of NaHSO3 on leaves, compared with the WT Kitaake rice, a greater enhancement of net photosynthetic rate was observed in PEPC transgenic (PC) and PEPC+PPDK transgenic (PC+PK) rice, with the greatest increase being observed in the latter group. Therefore ATP supply may become the limiting factor that concentrates CO2 in rice leaves transformed with an exogenous PEPC gene and exogenous PEPC+PPDK genes.
文摘Spraying 1-2 mmol/L NaHSO3 on the leaf of wheat results in enhancement of photosynthesis in leaves for about 3 d. The amount of ATP has been increased and the millisecond delayed light emission of the leaves has been enhanced, showing that the transmembrane proton motive force related to photophosphorylation is increased. Spraying PMS (a cofactor catalyzing cycle photophosphorylation) and NaHSO3 separately or together on the leaves, 20% increase in photosynthesis has been observed in all the treatments. There is no additive effect when a mixture is applied, suggesting that the mechanism for NaHSO3 promotion of photosynthesis is similar to PMS, and both of them enhance the supply of ATP.
基金We acknowledge the financial support from the National Natural Science Foundation of China(No.21677074)the Fundamental Research Funds for the Central Universities(No.021114380082).
文摘New and enhanced functions were potentially imparted to the plant organelles after interaction with nanoparticles.In this study,we found that∼44%and∼29%of the accumulated graphene in the rice leaves passively transported to the chloroplasts and thylakoid,respectively,significantly enhanced the fluorescence intensity of chloroplasts,and promoted about 2.4 times higher adenosine triphosphate production than that of controls.The enhancement of graphene on the photophosphorylation was ascribed to two reasons:One is that graphene facilitates the electron transfer process of photosystem II in thylakoid,and the other is that graphene protects the photosystem II against photo-bleaching by acting as a scavenger of reactive oxygen species.Overall,our work here confirmed that graphene translocating in the thylakoid promoted the photosynthetic activity of chloroplast in vivo and in vitro,providing new opportunities for designing biomimetic materials to enhance the solar energy conversion systems,especially for repairing or increasing the photosynthesis activity of the plants grown under stress environment.
基金supported by the National Natural Science Foundation of China (Grant No. 31271621)the Natural Science Foundation of the Jiangsu Ordinary Higher Education Institutions of China (Grant No. 11KJA180001)the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD), China
文摘Physiological, biochemical and electron microscopy analyses were used to investigate the photosynthetic performance of flag leaves in rice white stripe mutant 6001 during the senescence process. Results showed that the chlorophyll content at the heading and milk-ripe stages in rice mutant 6001 were about 34.78% and 3.00% less than those in wild type 6028, respectively. However, the chlorophyll content at the fully-ripe stage in rice mutant 6001 was higher than that in wild type 6028. At the heading stage, the net photosynthetic rate （Pn） in rice mutant 6001 was lower than that in wild type 6028. Rice mutant 6001 also exhibited a significantly slower decrease rate of Pn than wild type 6028 during the senescence progress, especially at the later stage. Furthermore, Ca2^-ATPase, Mg~^-ATPase and photophosphorylation activities exhibited the similar trends as the Po. During the senescence process, the 68 kDa polypeptide concentrations in the thylakoid membrane proteins exhibited a significant change, which was one of the critical factors that contributed to the observed change in photosynthesis. We also observed that the chloroplasts of rice mutant 6001 exhibited higher integrity than those of wild type 6028, and the chloroplast membrane of rice mutant 6001 disintegrated more slow during the senescence process. In general, rice mutant 6001 had a relatively slower senescence rate than wild type 6028, and exhibited anti-senescence properties.
