In order to improve the stormwater regulation functions of urban greenways on the basis of literature research and case study the relationships between urban greenway and low impact development LID and green stormwate...In order to improve the stormwater regulation functions of urban greenways on the basis of literature research and case study the relationships between urban greenway and low impact development LID and green stormwater infrastructure GSI are analyzed. Then the classification system of urban greenways is proposed based on their stormwater regulation function and the suitable technical measures for stormwater management which can be used in different kinds of greenways are selected. According to China’s urban planning system the greenway planning method combined with the urban drainage system is developed and the design methods of the greenway stormwater system and individual stormwater facilities are put forward. The relationships between the greenway stormwater system and other systems are also analyzed in terms of stormwater inlet vertical design and overflow.Finally the waterfront greenway and street greenway demonstration projects in Jiaxing City which adopts the above concept and method are introduced. The results show that the reduction rates of annual total stormwater runoff and average total runoff contaminants TSS of the stormwater system are not less than 30% and 40% respectively.展开更多
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
[Objective] The aim was to study the antialgal activities of allelochemical extracts from three terrestrial plant species.[Method] The allelochemicals were extracted from the leaves of Magnolia grandiflora,Sophora jap...[Objective] The aim was to study the antialgal activities of allelochemical extracts from three terrestrial plant species.[Method] The allelochemicals were extracted from the leaves of Magnolia grandiflora,Sophora japonica f.pendula and Buxus sinica (Rehd.et Wils.) Cheng by alcohol extraction,n-hexane,ethyl acetate and n-utanol phase.Furthermore antialgal activities of all components were determined.[Result] The active substances of M.grandiflora mainly existed in n-hexane and n-butanol phases.The active substances of S.japonica mainly existed in n-hexane phase,while the active substances of B.sinica mainly existed in ethyl acetate and aqueous phase.All the active substances showed significant antialgal activity (50% inhibition) after culture for 1 d except aqueous phase of B.sinica.In addition,inhibition rates of the tested phases increased with the increasing of culture duration and testing concentrations.The inhibition rates were over 90% against the growth of M.aeruginosa after culture for 7 d.The n-hexane and n-butanol phases of M.grandiflora exhibited the best antialgal activity,over 96% inhibition rate at the concentration of 25 μg/ml,which was significantly higher than those of the other components,furthermore it could cause shrinkage and obvious surface inanition of Microcystis aeruginosa.[Conclusion] The n-hexane and n-butanol phases of M.grandiflora have the best inhibition activities on the growth of Microcystis aeruginosa,so they are worthy of further study.展开更多
Pyrochlore structure La2Sn2O7:Eu3+ microcrystals with uniform octahedron shape were successfully synthesized via a hydrothermal route at 180 °C for 36 h. The crystal structure, particle size, morphologies, and ...Pyrochlore structure La2Sn2O7:Eu3+ microcrystals with uniform octahedron shape were successfully synthesized via a hydrothermal route at 180 °C for 36 h. The crystal structure, particle size, morphologies, and optical properties of the as-synthesized products were investigated by XRD, TEM, SEM, EDS, FT-IR, Raman spectroscopy and PL. The effects of pH of precursor solution, precursor concentration, reaction temperature, and time were investigated. The results reveal that pH of the precursor solution not only plays an important role in determining the phase of the as-synthesized products, but also has a significant influence on the morphologies of the samples. High-quality and uniform octahedrons with an average size of about 700 nm could be easily obtained at the pH value of 12. The possible formation mechanism of octahedral-like La2Sn2O7:Eu3+ microcrystals was briefly proposed. The photoluminescence spectra show that La2Sn2O7:Eu3+ micro-octahedra display stronger emission in the range of 582-592 nm compared with the samples with other shapes.展开更多
order to investigate the morphological response of freshwater green algae to elevated CO2 concentration, Chlamydomonas reinhardtii Dang and Scenedesmus obliquus Kutz were cultured with enriched CO2, and their microstr...order to investigate the morphological response of freshwater green algae to elevated CO2 concentration, Chlamydomonas reinhardtii Dang and Scenedesmus obliquus Kutz were cultured with enriched CO2, and their microstructure and ultrastructure were examined by microscopy and electron microscopy. The effect of CO2 enrichment to 186 mumol/L, was insignificant on the shape and size of C. reinhardtii, but significant in reducing the volume of S. obliquus. High-CO2 increased the amount of chloroplast. The pyrenoids occurred in low-CO2-grown cells but not in high-CO2-grown ones and more starch granules were observed in the former.展开更多
A high yielding rice mutant ( Oryza sativa L. cv. Zhenhui 249) with low chlorophyll b was recently discovered in the field. The mutant was mainly characterized by the decrease of the content of extrinsic antennae c...A high yielding rice mutant ( Oryza sativa L. cv. Zhenhui 249) with low chlorophyll b was recently discovered in the field. The mutant was mainly characterized by the decrease of the content of extrinsic antennae complex. This variation was shown in the stage when the leaves were expanding. When the leaves are at the final developmental stage, the content would approach to that of the wild type. It was discovered that only moderate amount of chlorophyll b decreased in this mutant. The photosynthetic apparatus of the mutant was rather stable in the whole life span of the leaf. The extrinsic antennae complex of the mutant might make efficient use of light and meanwhile reduce the production of O -· 2.展开更多
A green-revertible albino mutant-Qiufeng M was found from the japonica rice (Oryza sativa L. ssp. japonica) Qiufeng in the field. The first three leaves of the mutant were albino with some green. The leaf color beca...A green-revertible albino mutant-Qiufeng M was found from the japonica rice (Oryza sativa L. ssp. japonica) Qiufeng in the field. The first three leaves of the mutant were albino with some green. The leaf color became pale green since the fourth leaf and the glume had the same phenomenon as the first three leaves. The measuring data of the pigment content confirmed the visually observed results. It truly had a remarkable changing process in the leaf color in Qiufeng M. Comparison of the main agronomic characters between Qiufeng and Qiufeng M indicated that the neck length and grain weight showed significant difference at the 1% level, and other characters were not different. Genetic analysis showed that the green-revertible albino trait was controlled by a single recessive nucleic gene. Using 209 recessive mutant individuals in the F2 population derived from the cross Pei'ai 64S × Qiufeng M, a gene, tentatively named gra(t), was located between the SSR markers of RM475 and RM2-22 on the long arm of chromosome 2. The genetic distance were 17.3 cM and 2.9 cM respectively.展开更多
The cellular localization of Rubisco and Rubisco activase (RCA) in rice (Oryza sativa subsp. indica cv. Zhenong 952) leaf was investigated with immunogold-labeled electron microscope techniques on the basis of determi...The cellular localization of Rubisco and Rubisco activase (RCA) in rice (Oryza sativa subsp. indica cv. Zhenong 952) leaf was investigated with immunogold-labeled electron microscope techniques on the basis of determining the diurnal changes of photosynthetic rate (Pn), Rubisco and RCA activities, and quantifying two enzyme contents in the leaf with immuno-diffusion method in order to understand why RCA activity decreased in the midday when its contents was high. The results showed that Rubisco mainly was located in chloroplast, and RCA were found both in chloroplast and mitochondria. The lowering of Rubisco in chloroplast as well as Rubisco activity at noon could be one of good reasons to explain the photosynthetic midday depression in leaf. The density of RCA in chloroplast reached the maximum at 14:00 and a valley at 11:00. The result much coincided with the activity of RCA in leaf. In mitochondria, the density of RCA changed abruptly in one day with the highest at 13:00 and it can well elucidate why the activities of Rubisco declined at noon when its amount was increasing. Therefore the cellular localization and/or distribution of Rubisco and RCA during a day is more important for Pn, Rubisco and RCA activities.展开更多
[Objective] This study aimed at exploring the utilization rate of water of the new water-saving rice variety "Luhan No.1" and providing references and basis for the further demonstration and extension.[Method] Water...[Objective] This study aimed at exploring the utilization rate of water of the new water-saving rice variety "Luhan No.1" and providing references and basis for the further demonstration and extension.[Method] Water-saving rice variety "Luhan No.1" and original receptor "6527" were used for dry processing without aquifer,and rice under regular irrigation conditions was used as the control.[Result] Under conditions which had economized on 67.4% of water compared with the regular irrigation,decreasing rates of 1 000-seed weight,seed setting rate,plant height and effective panicles of "Luhan No.1" were relatively small and had not achieved a significant level,while the decreasing rates of production of the region,total grains per panicle,theoretical production and filled grains per panicle of the original receptor "6527" were all over 25% and had attained very significant levels(P0.01).[Conclusion] "Luhan No.1" had shown stable production,energy conservation,reducing environmental pollution and other advantages under water-conservating cultivation conditions.展开更多
[Objective] The experiment aimed to explore physiological and biochemical changes of leaves after plants were mutated. [Method] A rice double mutant with stripes on stems, leaves and spikelets were taken as experiment...[Objective] The experiment aimed to explore physiological and biochemical changes of leaves after plants were mutated. [Method] A rice double mutant with stripes on stems, leaves and spikelets were taken as experimental materials to study the enzyme activity changes in different growth stages and amino acid variation in rice. [ Result] The SOD activity in mutant was higher than that in wild plant at tillering metaphase, but lower than that in wild type before heading stage and late flowering; the POD activity in three stages increased firstly then declined and the activity showed highest maximal activity at before heading stage. However, the POD activity in wild type showed the opposite change trend; the CAT activity presented degression at three stages, especially high at tillering metaphase, but reverse changes in wild type; the MDA activity decreased at three stages, but it was still higher than that in wild type, besides, the soluble sugar content of mutant was lower, but total amino acid content was increased. [ Conclusion] The expression of mutant characteristics was correlated with SOD, POD, CAT and MDA activity Changes and these changes made the mutant survive and rice quality change at last.展开更多
Economic development around the Daya Bay, China has profoundly affected the marine environment in the bay area in recent years, particularly since the operation of Daya Bay Nuclear Power Station (DNPS) in 1994. This...Economic development around the Daya Bay, China has profoundly affected the marine environment in the bay area in recent years, particularly since the operation of Daya Bay Nuclear Power Station (DNPS) in 1994. This study analyzed the changes of water temperature and harmful algal blooms (HABs) for two periods: 1983-1993 and 1994-2004, using in situ and satellite data. Results showed that yearly mean surface water temperature (SWT) and Chl-a concentration (Chl-a) increased by 1.1 ℃ and 1.9 mg/m^3, respectively, after 1994. The monthly occurrence of HAB was found to have increased also. HABs appeared only in spring and autumn before 1994, but occurred all the year round after 1994. SWT, Chl-a and HABs all increased significantly in May. Those changes were associated with environmental changes in this area, such as thermal discharge from the DNPS and enhancement of eutrophication from human activities around the Daya Bay.展开更多
The chlorophyll fluorescence kinetics of marine red alga Grateloupia turutunt Yamada, green alga Ulva pertusa Kjellm and brown alga Laminaria japonica Aresch during natural sustained dehydration were monitored and inv...The chlorophyll fluorescence kinetics of marine red alga Grateloupia turutunt Yamada, green alga Ulva pertusa Kjellm and brown alga Laminaria japonica Aresch during natural sustained dehydration were monitored and investigated. The pulse amplified modulation (PAM) system was used to analyze the distinct fluorescence parameters during thallus dehydration. Results proved that the fluorescence kinetics of different seaweed all showed three patterns of transformation with sustained water loss. These were: 1) peak kinetic pattern (at the early stage of dehydration fluorescence enhanced and quenched subsequently, representing a normal physiological state). 2) plateau kinetic pattern (with sustained water loss fluorescence enhanced continuously but quenching became slower, finally reaching its maximum). 3) Platform kinetic pattern (fluorescence fell and the shape of kinetic curve was similar to plateau kinetic pattern). A critical water content (CWC) could be found and defined as the percentage of water content just prior to the fluorescence drop and to be a significant physiological index for evaluation of plant drought tolerance. Once thallus water content became lower than this value the normal peak pattern can not be recovered even through rehydration, indicating an irreversible damage to the thylakoid membrane. The CWC value corresponding to different marine species were varied and negatively correlated with their desiccation tolerance, for example. Laminaria japonica had the highest CWC value (around 90%) and the lowest dehydration tolerance of the three. In addition, a fluorescence 'burst' was found only in red algae during rehydration. The different fluorescence parameters F-o, F-v and F-v, F-m were measured and compared during water loss. Both F-o and F-v increased in the first stage of dehydration but F-v/F-m. kept almost constant. So the immediate response of in vivo chlorophyll fluorescence to dehydration was an enhancement. Later with sustained dehydration F-o increased continuously while F-v decreased and tended to become smaller and smaller. The major changes in fluorescence (including fluorescence drop during dehydration and the burst during rehydration) were all attributed to the change in F-o instead of F-v This significance of F-o indicates that it is necessary to do more research on F-o as well as on its relationship with the state of thylakoid membrane.展开更多
This study aimed to investigate the effects of different precooling treatments(0 ℃ ice water, 4 ℃ cold water and 4 ℃ refrigerator) on the physiological characteristics of post-harvest cowpea. The results showed t...This study aimed to investigate the effects of different precooling treatments(0 ℃ ice water, 4 ℃ cold water and 4 ℃ refrigerator) on the physiological characteristics of post-harvest cowpea. The results showed that precooling treatments could effectively maintain the sensory quality and slow the loss of nutrients of cowpea. Among the treatments, cold water precooling showed the best freshkeeping effect on post-harvest cowpea. It slowed the decline of sensory quality of post-harvest cowpea, inhibited the increase of weight loss rate, ethylene release amount, relative conductivity and malondialdehyde(MDA) content, and the degradation of total soluble solids(TSS), vitamin C, chlorophyll and soluble protein, and improved the activities of catalase(CAT) and peroxidase(POD).展开更多
Using various high-yield rices (Oryza sativa L.) such as japonica cultivar 9516, two parental line hybrid rice between subspecies with more japonica element Peiai 64/E32, Liangyoupeijiu (Peiai 64/9311), and indica hyb...Using various high-yield rices (Oryza sativa L.) such as japonica cultivar 9516, two parental line hybrid rice between subspecies with more japonica element Peiai 64/E32, Liangyoupeijiu (Peiai 64/9311), and indica hybrid rices X07S/Zihui 100, Gangyou 881, Shanyou 63 as the materials, the characteristics of chlorophyll fluorescence and membrane-lipid peroxidation of detached leaves at booting stage under photooxidation conditions were studied. In comparison with indica hybrid rice, after the photooxidation treatment, the primary photochemical efficiency of PS II (F-v/F-m), quantum yield of linear electron transport of PS II (Phi(PSII)) and photochemical quenching coefficient (qP) in japonica cultivar and hybrid rice with japonica decreased less. This indicated that high-yield rice with japonica was able to maintain higher capability of light energy conversion, resulting in the alleviation of photoinhibition. Meanwhile, the higher activities of protective enzymes such as superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD) led to the less accumulation of endogenous active oxygen (O-(2)(radical anion), H2O2) and less content of the malondialdehyde (MDA) and the less decline of chlorophyll and protein contents, indicating a stronger tolerance to photooxidation. The changes in contents of chlorophyll and protein among various nee cultivars during photooxidation treatment were consistent with the decline of chlorophyll content from heading stage to maturation stage under natural conditions. Statistical analysis showed that there was a significant correlation between the indexes of tolerance to photooxidation and the rate of seed setting, implying that the cultivar tolerated to photooxidation had higher resistance to early aging of leaf. These results suggested that from a view of superhigh-yield breeding, considering both the utilization of heterosis and the resistance to early aging of leaf, introduction of japonica element tolerating to photooxidation into the rice sterile line (maternal plant) is a breeding strategy worthy to pay great attention to.展开更多
[Objective] This study aimed to test whether salicylic acid (SA) can im-prove the physiological functions of flue-cured tobacco under subdued light condition, and to determine the mechanism of its action. [Method] T...[Objective] This study aimed to test whether salicylic acid (SA) can im-prove the physiological functions of flue-cured tobacco under subdued light condition, and to determine the mechanism of its action. [Method] The tobacco plants under subdued light were foliar-sprayed with 100 mg/L of SA. Then, the physiological in-dices such as plant fresh weight and dry weight, chlorophyl content, photosynthetic parameters and chlorophyl fluorescence parameters were measured. SPSS17.0 and Excellwere adopted for variance analysis and significance test. [Result] The leaf photosynthetic rate (Pn), stomatal conductance (Gs) and transpiration rate (Tr) of tobacco plants in subdued light were al decreased while the intercellular CO2 con-centration (Ci) was increased, suggesting that non-stomatal limitation led to the de-crease of Pn under weak light intensity stress. SA released the inhibition of tobacco plant growth in weak light, as it elevated the leaf photosynthetic rate, the maximum photochemical efficiency of PSⅡ, potential activity of PSⅡ, effective photochemical efficiency of PSⅡ and photochemical quenching coefficient in weak light significant-ly, and reduced the non-photochemical quenching coefficient. [Conclusion] SA has significant effects on the photosynthetic characteristics of flue-cured tobacco in weak light, and it can improve the synthesis or distribution of photosynthesis product, and the efficiency of light energy, conducive to plant growth and development.展开更多
基金The National Natural Science Foundation of China(No.51208020)
文摘In order to improve the stormwater regulation functions of urban greenways on the basis of literature research and case study the relationships between urban greenway and low impact development LID and green stormwater infrastructure GSI are analyzed. Then the classification system of urban greenways is proposed based on their stormwater regulation function and the suitable technical measures for stormwater management which can be used in different kinds of greenways are selected. According to China’s urban planning system the greenway planning method combined with the urban drainage system is developed and the design methods of the greenway stormwater system and individual stormwater facilities are put forward. The relationships between the greenway stormwater system and other systems are also analyzed in terms of stormwater inlet vertical design and overflow.Finally the waterfront greenway and street greenway demonstration projects in Jiaxing City which adopts the above concept and method are introduced. The results show that the reduction rates of annual total stormwater runoff and average total runoff contaminants TSS of the stormwater system are not less than 30% and 40% respectively.
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Supported by National Natural Science Foundation of China(30671240, 30871588)~~
文摘[Objective] The aim was to study the antialgal activities of allelochemical extracts from three terrestrial plant species.[Method] The allelochemicals were extracted from the leaves of Magnolia grandiflora,Sophora japonica f.pendula and Buxus sinica (Rehd.et Wils.) Cheng by alcohol extraction,n-hexane,ethyl acetate and n-utanol phase.Furthermore antialgal activities of all components were determined.[Result] The active substances of M.grandiflora mainly existed in n-hexane and n-butanol phases.The active substances of S.japonica mainly existed in n-hexane phase,while the active substances of B.sinica mainly existed in ethyl acetate and aqueous phase.All the active substances showed significant antialgal activity (50% inhibition) after culture for 1 d except aqueous phase of B.sinica.In addition,inhibition rates of the tested phases increased with the increasing of culture duration and testing concentrations.The inhibition rates were over 90% against the growth of M.aeruginosa after culture for 7 d.The n-hexane and n-butanol phases of M.grandiflora exhibited the best antialgal activity,over 96% inhibition rate at the concentration of 25 μg/ml,which was significantly higher than those of the other components,furthermore it could cause shrinkage and obvious surface inanition of Microcystis aeruginosa.[Conclusion] The n-hexane and n-butanol phases of M.grandiflora have the best inhibition activities on the growth of Microcystis aeruginosa,so they are worthy of further study.
基金Project (07C26214301746) supported by Innovation Foundation of Ministry of Science and Technology, ChinaProject (2010GXNSFB013008) supported by Guangxi Natural Science Foundation, ChinaProject (2009bsxt001) supported by the Graduate Degree Thesis Innovation Foundation of Central South University, China
文摘Pyrochlore structure La2Sn2O7:Eu3+ microcrystals with uniform octahedron shape were successfully synthesized via a hydrothermal route at 180 °C for 36 h. The crystal structure, particle size, morphologies, and optical properties of the as-synthesized products were investigated by XRD, TEM, SEM, EDS, FT-IR, Raman spectroscopy and PL. The effects of pH of precursor solution, precursor concentration, reaction temperature, and time were investigated. The results reveal that pH of the precursor solution not only plays an important role in determining the phase of the as-synthesized products, but also has a significant influence on the morphologies of the samples. High-quality and uniform octahedrons with an average size of about 700 nm could be easily obtained at the pH value of 12. The possible formation mechanism of octahedral-like La2Sn2O7:Eu3+ microcrystals was briefly proposed. The photoluminescence spectra show that La2Sn2O7:Eu3+ micro-octahedra display stronger emission in the range of 582-592 nm compared with the samples with other shapes.
文摘order to investigate the morphological response of freshwater green algae to elevated CO2 concentration, Chlamydomonas reinhardtii Dang and Scenedesmus obliquus Kutz were cultured with enriched CO2, and their microstructure and ultrastructure were examined by microscopy and electron microscopy. The effect of CO2 enrichment to 186 mumol/L, was insignificant on the shape and size of C. reinhardtii, but significant in reducing the volume of S. obliquus. High-CO2 increased the amount of chloroplast. The pyrenoids occurred in low-CO2-grown cells but not in high-CO2-grown ones and more starch granules were observed in the former.
文摘A high yielding rice mutant ( Oryza sativa L. cv. Zhenhui 249) with low chlorophyll b was recently discovered in the field. The mutant was mainly characterized by the decrease of the content of extrinsic antennae complex. This variation was shown in the stage when the leaves were expanding. When the leaves are at the final developmental stage, the content would approach to that of the wild type. It was discovered that only moderate amount of chlorophyll b decreased in this mutant. The photosynthetic apparatus of the mutant was rather stable in the whole life span of the leaf. The extrinsic antennae complex of the mutant might make efficient use of light and meanwhile reduce the production of O -· 2.
基金This work was supported by the Major Research Program on Technology of Agricultural Structure Adjustment (No. 05-01-05B)Jiangsu High Technology Program (No. BG2004301, BG2004304, and BG2005301).
文摘A green-revertible albino mutant-Qiufeng M was found from the japonica rice (Oryza sativa L. ssp. japonica) Qiufeng in the field. The first three leaves of the mutant were albino with some green. The leaf color became pale green since the fourth leaf and the glume had the same phenomenon as the first three leaves. The measuring data of the pigment content confirmed the visually observed results. It truly had a remarkable changing process in the leaf color in Qiufeng M. Comparison of the main agronomic characters between Qiufeng and Qiufeng M indicated that the neck length and grain weight showed significant difference at the 1% level, and other characters were not different. Genetic analysis showed that the green-revertible albino trait was controlled by a single recessive nucleic gene. Using 209 recessive mutant individuals in the F2 population derived from the cross Pei'ai 64S × Qiufeng M, a gene, tentatively named gra(t), was located between the SSR markers of RM475 and RM2-22 on the long arm of chromosome 2. The genetic distance were 17.3 cM and 2.9 cM respectively.
文摘The cellular localization of Rubisco and Rubisco activase (RCA) in rice (Oryza sativa subsp. indica cv. Zhenong 952) leaf was investigated with immunogold-labeled electron microscope techniques on the basis of determining the diurnal changes of photosynthetic rate (Pn), Rubisco and RCA activities, and quantifying two enzyme contents in the leaf with immuno-diffusion method in order to understand why RCA activity decreased in the midday when its contents was high. The results showed that Rubisco mainly was located in chloroplast, and RCA were found both in chloroplast and mitochondria. The lowering of Rubisco in chloroplast as well as Rubisco activity at noon could be one of good reasons to explain the photosynthetic midday depression in leaf. The density of RCA in chloroplast reached the maximum at 14:00 and a valley at 11:00. The result much coincided with the activity of RCA in leaf. In mitochondria, the density of RCA changed abruptly in one day with the highest at 13:00 and it can well elucidate why the activities of Rubisco declined at noon when its amount was increasing. Therefore the cellular localization and/or distribution of Rubisco and RCA during a day is more important for Pn, Rubisco and RCA activities.
基金Supported by National863Green Super Rice Project"Water-saving and Drought-resistant Rice Germplasm Innovation"(2010AA101803)Anhui Province Foreign Expert Bureau Agricultural Introduction and Promotion Project"Demonstration and Extension of National Authorized Dry Rice Variety'Luhan No.1'"(Y20083400015)~~
文摘[Objective] This study aimed at exploring the utilization rate of water of the new water-saving rice variety "Luhan No.1" and providing references and basis for the further demonstration and extension.[Method] Water-saving rice variety "Luhan No.1" and original receptor "6527" were used for dry processing without aquifer,and rice under regular irrigation conditions was used as the control.[Result] Under conditions which had economized on 67.4% of water compared with the regular irrigation,decreasing rates of 1 000-seed weight,seed setting rate,plant height and effective panicles of "Luhan No.1" were relatively small and had not achieved a significant level,while the decreasing rates of production of the region,total grains per panicle,theoretical production and filled grains per panicle of the original receptor "6527" were all over 25% and had attained very significant levels(P0.01).[Conclusion] "Luhan No.1" had shown stable production,energy conservation,reducing environmental pollution and other advantages under water-conservating cultivation conditions.
基金Supported by Program for New Century Excellent Talents in University(NCET-04-0907)the Innovative Research Team in University (IRT0453)~~
文摘[Objective] The experiment aimed to explore physiological and biochemical changes of leaves after plants were mutated. [Method] A rice double mutant with stripes on stems, leaves and spikelets were taken as experimental materials to study the enzyme activity changes in different growth stages and amino acid variation in rice. [ Result] The SOD activity in mutant was higher than that in wild plant at tillering metaphase, but lower than that in wild type before heading stage and late flowering; the POD activity in three stages increased firstly then declined and the activity showed highest maximal activity at before heading stage. However, the POD activity in wild type showed the opposite change trend; the CAT activity presented degression at three stages, especially high at tillering metaphase, but reverse changes in wild type; the MDA activity decreased at three stages, but it was still higher than that in wild type, besides, the soluble sugar content of mutant was lower, but total amino acid content was increased. [ Conclusion] The expression of mutant characteristics was correlated with SOD, POD, CAT and MDA activity Changes and these changes made the mutant survive and rice quality change at last.
基金This study was jointly supported by the following funds awarded to Professor Danling TANG:Guangdong Natural Science Foundation(05102008 and 04001306),ChinaKey Innovation Project of Chinese Academy of Sciences(CAS)(KZCX3-SW-227-3)+3 种基金"0ne Hundred Talents Program"of CAS(Ybrjh0403)Authors are grateful to projects of South China Sea Fisheries Research Institute,Chinese Academy of Fishery Sciences(2007TS10 and 2007ZD03)High-tech Research and Development Program of China(2006AA100303)Chinese Ecosystem Research Network(http://www.cerndata.ac.cn),Dr.Guifeng WEI of Jinan University and the Key Innovation Project of CAS(KZCX3-SW-214).
文摘Economic development around the Daya Bay, China has profoundly affected the marine environment in the bay area in recent years, particularly since the operation of Daya Bay Nuclear Power Station (DNPS) in 1994. This study analyzed the changes of water temperature and harmful algal blooms (HABs) for two periods: 1983-1993 and 1994-2004, using in situ and satellite data. Results showed that yearly mean surface water temperature (SWT) and Chl-a concentration (Chl-a) increased by 1.1 ℃ and 1.9 mg/m^3, respectively, after 1994. The monthly occurrence of HAB was found to have increased also. HABs appeared only in spring and autumn before 1994, but occurred all the year round after 1994. SWT, Chl-a and HABs all increased significantly in May. Those changes were associated with environmental changes in this area, such as thermal discharge from the DNPS and enhancement of eutrophication from human activities around the Daya Bay.
文摘The chlorophyll fluorescence kinetics of marine red alga Grateloupia turutunt Yamada, green alga Ulva pertusa Kjellm and brown alga Laminaria japonica Aresch during natural sustained dehydration were monitored and investigated. The pulse amplified modulation (PAM) system was used to analyze the distinct fluorescence parameters during thallus dehydration. Results proved that the fluorescence kinetics of different seaweed all showed three patterns of transformation with sustained water loss. These were: 1) peak kinetic pattern (at the early stage of dehydration fluorescence enhanced and quenched subsequently, representing a normal physiological state). 2) plateau kinetic pattern (with sustained water loss fluorescence enhanced continuously but quenching became slower, finally reaching its maximum). 3) Platform kinetic pattern (fluorescence fell and the shape of kinetic curve was similar to plateau kinetic pattern). A critical water content (CWC) could be found and defined as the percentage of water content just prior to the fluorescence drop and to be a significant physiological index for evaluation of plant drought tolerance. Once thallus water content became lower than this value the normal peak pattern can not be recovered even through rehydration, indicating an irreversible damage to the thylakoid membrane. The CWC value corresponding to different marine species were varied and negatively correlated with their desiccation tolerance, for example. Laminaria japonica had the highest CWC value (around 90%) and the lowest dehydration tolerance of the three. In addition, a fluorescence 'burst' was found only in red algae during rehydration. The different fluorescence parameters F-o, F-v and F-v, F-m were measured and compared during water loss. Both F-o and F-v increased in the first stage of dehydration but F-v/F-m. kept almost constant. So the immediate response of in vivo chlorophyll fluorescence to dehydration was an enhancement. Later with sustained dehydration F-o increased continuously while F-v decreased and tended to become smaller and smaller. The major changes in fluorescence (including fluorescence drop during dehydration and the burst during rehydration) were all attributed to the change in F-o instead of F-v This significance of F-o indicates that it is necessary to do more research on F-o as well as on its relationship with the state of thylakoid membrane.
基金Supported by National Staple Vegetable Industrial Technology System(CARS-25)Research and Demonstration Project for Horticultural Crop Eco-efficient Production Technology in Non-arable Lands in Northwest China(201203095)Youth Foundation of Beijing Academy of Agriculture and Forestry Sciences(201404)~~
文摘This study aimed to investigate the effects of different precooling treatments(0 ℃ ice water, 4 ℃ cold water and 4 ℃ refrigerator) on the physiological characteristics of post-harvest cowpea. The results showed that precooling treatments could effectively maintain the sensory quality and slow the loss of nutrients of cowpea. Among the treatments, cold water precooling showed the best freshkeeping effect on post-harvest cowpea. It slowed the decline of sensory quality of post-harvest cowpea, inhibited the increase of weight loss rate, ethylene release amount, relative conductivity and malondialdehyde(MDA) content, and the degradation of total soluble solids(TSS), vitamin C, chlorophyll and soluble protein, and improved the activities of catalase(CAT) and peroxidase(POD).
文摘Using various high-yield rices (Oryza sativa L.) such as japonica cultivar 9516, two parental line hybrid rice between subspecies with more japonica element Peiai 64/E32, Liangyoupeijiu (Peiai 64/9311), and indica hybrid rices X07S/Zihui 100, Gangyou 881, Shanyou 63 as the materials, the characteristics of chlorophyll fluorescence and membrane-lipid peroxidation of detached leaves at booting stage under photooxidation conditions were studied. In comparison with indica hybrid rice, after the photooxidation treatment, the primary photochemical efficiency of PS II (F-v/F-m), quantum yield of linear electron transport of PS II (Phi(PSII)) and photochemical quenching coefficient (qP) in japonica cultivar and hybrid rice with japonica decreased less. This indicated that high-yield rice with japonica was able to maintain higher capability of light energy conversion, resulting in the alleviation of photoinhibition. Meanwhile, the higher activities of protective enzymes such as superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD) led to the less accumulation of endogenous active oxygen (O-(2)(radical anion), H2O2) and less content of the malondialdehyde (MDA) and the less decline of chlorophyll and protein contents, indicating a stronger tolerance to photooxidation. The changes in contents of chlorophyll and protein among various nee cultivars during photooxidation treatment were consistent with the decline of chlorophyll content from heading stage to maturation stage under natural conditions. Statistical analysis showed that there was a significant correlation between the indexes of tolerance to photooxidation and the rate of seed setting, implying that the cultivar tolerated to photooxidation had higher resistance to early aging of leaf. These results suggested that from a view of superhigh-yield breeding, considering both the utilization of heterosis and the resistance to early aging of leaf, introduction of japonica element tolerating to photooxidation into the rice sterile line (maternal plant) is a breeding strategy worthy to pay great attention to.
基金Suported by the Special Fund of China National Flue-Cured Tobacco Corporation for Development of Specifc and High-quality Tobbaco Leaf[110201101001(TS-01)]~~
文摘[Objective] This study aimed to test whether salicylic acid (SA) can im-prove the physiological functions of flue-cured tobacco under subdued light condition, and to determine the mechanism of its action. [Method] The tobacco plants under subdued light were foliar-sprayed with 100 mg/L of SA. Then, the physiological in-dices such as plant fresh weight and dry weight, chlorophyl content, photosynthetic parameters and chlorophyl fluorescence parameters were measured. SPSS17.0 and Excellwere adopted for variance analysis and significance test. [Result] The leaf photosynthetic rate (Pn), stomatal conductance (Gs) and transpiration rate (Tr) of tobacco plants in subdued light were al decreased while the intercellular CO2 con-centration (Ci) was increased, suggesting that non-stomatal limitation led to the de-crease of Pn under weak light intensity stress. SA released the inhibition of tobacco plant growth in weak light, as it elevated the leaf photosynthetic rate, the maximum photochemical efficiency of PSⅡ, potential activity of PSⅡ, effective photochemical efficiency of PSⅡ and photochemical quenching coefficient in weak light significant-ly, and reduced the non-photochemical quenching coefficient. [Conclusion] SA has significant effects on the photosynthetic characteristics of flue-cured tobacco in weak light, and it can improve the synthesis or distribution of photosynthesis product, and the efficiency of light energy, conducive to plant growth and development.