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The effects of enriched C0_(2) and enhanced UV-B radiation on ultrastructure of Dunaliella salina, singly and in combination 被引量:1
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作者 YU Juan XIAO Hui +3 位作者 TIAN Jiyuan ZHANG Peiyu DONG Shuanglin TANG Xuexi 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2006年第1期137-146,共10页
The effects of ambient CO2/ambient UV-B, enriched CO2/ambient UV-B, ambient CO2/enhanced UV-B, and enriched CO2/enhanced UV-B on the ultrastructure of Dunaliella salina were investigated. (1) The ultrastructure of D... The effects of ambient CO2/ambient UV-B, enriched CO2/ambient UV-B, ambient CO2/enhanced UV-B, and enriched CO2/enhanced UV-B on the ultrastructure of Dunaliella salina were investigated. (1) The ultrastructure of D..salina cell in the control experiment showed that the arrangement of thylakoid lamellae was regular, and there were many large starch grains among the thylakoid lamellae. A prominent well-developed pyrenoid was found in the middle of the chloroplast. Nucleus envelope and nucleolus were clearly observed. The Golgi apparatus accompanied by numerous vesicles with a compact arrangement of cisternae and the peripheral tips of the cisternae were swollen to a size comparable to that of some of the associated vesicles. (2) The ultrastructure of D. salina cell in enriched CO2 showed that the arrangement of thylakoid was regular and the lamellae were vivid. Developed pyrenoids were found in the low-CO2-grown cells, but not in the high-CO2-grown cells. The mitochondria cristae were vivid. The arrangement of Golgi apparatus was compact. (3) The ultrastructure of D. salina cell in enhanced UV-B showed that the thylakoid was dissolved and the cells had a less developed pyrenoid or no detectable pyrenoid. Part of the nucleus envelope was dissolved. The number ofmitochondria was increased and some mitochondria cristae were disintegrated. The starch grains were broken apart into many small starch grains. The Golgi apparatus with a loose arrangement ofcistemae and the peripheral tips of the Golgi cistemae were not especially swollen, with several large associated vesicles. (4) The ultrastructure of D. salina cell in the enriched CO2/enhanced UV-B showed that part of the thylakoid and nucleus envelopes of some cells were dissolved. The pyrenoid was larger than that of the enhanced UV-B. There were many mitochondria between stroma and chloroplast membrane, but mitochondria cristae were partly dissolved. Many small starch grains were accumulated in cells. The starch sheath was broken into several discontinuous starch grains with different sizes. The arrangement of Golgi apparatus was loose. Above all, although the enriched CO2 can alleviate the damage induced by the UV-B radiation, the effects of experimental UV-B radiation were larger than the effects of actual UV-B radiation, the damage induced by the UV-B radiation was so severe, therefore, CO2 enrichment could not restore the ultrastructure to the control level. 展开更多
关键词 enriched CO2 enhanced uv-b radiation ULTRASTRUCTURE Dunaliella salina
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Effect of Enhanced UV-B Radiation on Seed Setting Rate and 1 000-grain Weight of Indica Hybrid Rice Restorer Lines
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作者 况浩池 曾祥瑞 +5 位作者 罗俊涛 曾正明 杨扬 陈光珍 何兴材 付均 《Agricultural Science & Technology》 CAS 2013年第2期226-229,共4页
[Objective] This study was to investigate the effect of enhanced UV-B radiation on seed setting rate and 1 000-grain weight of hybrid rice combinations. [Method] The seed setting rate and 1 000-grain weight of 10 new ... [Objective] This study was to investigate the effect of enhanced UV-B radiation on seed setting rate and 1 000-grain weight of hybrid rice combinations. [Method] The seed setting rate and 1 000-grain weight of 10 new sterile indica restorer lines planted in pots under enhanced UV-B radiation and fluorescent lamps (control) were respectively measured, and the differences were compared. [Result] The enhanced UV-B radiation significantly reduced the seed setting rate of indica restorer lines, and the differences between that UV-B radiation treatment and control all reached extremely significant level. In addition, the enhanced UV-B radiation reduced the 1 000-grain weight of most indica restorer lines, and compared with that of control the difference achieved significant or very significant level. However, the effect of enhanced UV-B radiation on seed setting rate and 1 000-grain weight differed to different indica restorer lines, and the differences among restorer lines tested were significant or very significant, which indicated the possibility to screen antiUV-B radiation rice materials and combinations. Finally, the indica restorer lines 09R-14, Luhui 37 and 10R-7703 which were strongly resistant to UV-B radiation were screened out. [Conclusion] This study laid foundation for breeding hybrid rice varieties resistance to UV-B radiation. 展开更多
关键词 uv-b radiation Indica restorer lines Hybrid rice Seed setting rate Grain weight
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Response of Marine Microalgae,Heterotrophic Bacteria and Their Relationship to Enhanced UV-B Radiation
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作者 ZHOU Wenli TANG Xuexi +2 位作者 XIAO Hui WANG You WANG Renjun 《Journal of Ocean University of China》 SCIE CAS 2009年第1期35-38,共4页
Ozone depletion in the stratosphere has enhanced solar UV-B radiation reaching the Earth surface and has brought about significant effects to marine ecosystems. The effects of enhanced UV-B radiation on marine microal... Ozone depletion in the stratosphere has enhanced solar UV-B radiation reaching the Earth surface and has brought about significant effects to marine ecosystems. The effects of enhanced UV-B radiation on marine microalgae, heterotrophic bacteria and the interaction between them are discussed. The effects on marine microalgae have been proved to occur at molecular, cellular and population levels. Enhanced UV-B radiation increases microalgal flavonoid content but decreases their chlorophyll content and pho- tosynthesis rate; this radiation induces genetic change and results in DNA damage and change of protein content. There have been fewer studies on the effects of UV-B radiation on marine heterotrophic bacteria. Establishment of a microalgal ecological dynamic model at population and commuity levels under UV-B radiation has gradually become a hotspot. The effects of enhanced UV-B radiation on microalgae commtmities, heterotrophic bacterial populations and interaction between them will become a focus in the near future. This paper will make an overview on the studies concerning the effects of enhanced UV-B radiation on marine microalgae and heterotrophic bacteria and the interaction between them. 展开更多
关键词 uv-b radiation EFFECT MICROALGAE heterotrophic bacteria
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Different Doses of the Enhanced UV-B Radiation Effects on Wheat Somatic Cell Division
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作者 Feifeng Liu Huize Chen Rong Han 《CellBio》 2015年第2期30-36,共7页
Being sessile, plants are continuously exposed to DNA-damaging agents presenting in the environment such as ultraviolet (UV). Sunlight acts as an energy source for photosynthetic plants;hence, avoidance of UV radiatio... Being sessile, plants are continuously exposed to DNA-damaging agents presenting in the environment such as ultraviolet (UV). Sunlight acts as an energy source for photosynthetic plants;hence, avoidance of UV radiations (namely, UV-A, 315 - 400 nm;UV-B, 280 - 315 nm;and UV-C, 1 group: 4.05 kJ&#8226m-2&#8226d-1, B2 group: 10.08 kJ&#8226m-2&#8226d-1, B3 group: 7.05 kJ&#8226m-2&#8226d-1, B4 group: 23.02 kJ&#8226m-2&#8226d-1) treatment wheat, then, explored on the growth of wheat root and wheat root tip cell of chromosome aberration effect. In wheat, root-tip cells were observed with confocal laser scanning microscopy (CLSM), the results showed that low doses of B1 group (4.05 kJ&#8226m-2&#8226d-1) promoted the growth of wheat root and cell mitosis frequency. But high dose of B2 group (10.08 kJ&#8226m-2&#8226d-1), B3 group (17.05 kJ&#8226m-2&#8226d-1), B4 group (23.02 kJ&#8226m-2&#8226d-1) inhibited the growth of wheat root tip, and made crooked growth of wheat root, and inhibited the wheat root tip cell mitotic frequency and processed that induce root tip cells of wheat produce all kinds of aberration of chromosome in the interphase containing “multiple nucleoli nuclei”, “incomplete nuclei”, “long round nuclei”, “bean sprouts nucleus”. In mitosis M period contains “dissociative chromosome”, “chromosome bridge”, “adhesion chromosome”, “multi-bundle divide”, “nuclear anomalies”. After, high doses of enhanced UV-B radiation treatment, most of the cell cycle anomaly concentrated in mitosis interphase. In mitosis M period, with UV-B radiation dose enhanced chromosome aberration rate was on the rise and the aberration types also increasing. 展开更多
关键词 WHEAT enhanced uv-b radiation CHROMOSOME ABERRATION CONFOCAL Laser Scanning Microscopy (CLSM)
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Ethylene Production and 1-Aminocyclopropane-l-Carboxylate (ACC) Synthase Gene Expression in Tomato ( L ycopsicon esculentum Mill.) Leaves Under Enhanced UV-B Radiation 被引量:2
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作者 Lizhe An Xiaofeng Xu +7 位作者 Hongguan Tang Manxiao Zhang Zongdong HOU Yanhong Liu Zhiguang Zhao Huyuan Feng Shijian Xu Xunling Wang 《Journal of Integrative Plant Biology》 SCIE CAS CSCD 2006年第10期1190-1196,共7页
Tomato (Lycopslcon esculentum Mill.) plants grown in a greenhouse were irradiated with two different levels of UV-B, namely 8.82 (T1) and 12.6 kJ/m^2 per day (T2). Ethylene production, 1-aminocyclopropane-1-carb... Tomato (Lycopslcon esculentum Mill.) plants grown in a greenhouse were irradiated with two different levels of UV-B, namely 8.82 (T1) and 12.6 kJ/m^2 per day (T2). Ethylene production, 1-aminocyclopropane-1-carboxylate (ACC) content, 1-(malonylamino) cyclopvopane-1-carboxylic acid (MACC) content, gene expression of ACC aynthase (EC 4.4.1.14), and ACC oxidase activity in tomato leaves were determined. The results Indicated that ACC content, the activity of ACC synthase and ACC oxidase, and ethylene production Increased continuously under low doses of UV-B radiation, whereas at high doses of radiation these parameters Increased during the first 12 d and then started to decrease. The MACC content increased continuously over 18 d under both doses of UV-B irradiation. The changes in ACC content, ACC synthaae activity, ACC oxidase activity, the transcriptional level of the ACC synthase gene, and ethylene production were consistent with each other, suggesting that ACC synthase was the key enzyme in ethylene biosynthesis and that ethylene production in tomato leaf tissues under UV-B radiation could be regulated by the expression of the ACC synthase gene. The results also indicate that the change in ethylene metabolism may be an adaptive mechanism to enhanced UV-B radiation. 展开更多
关键词 enhanced uv-b radiation ethylene production gene expression of 1-aminocyclopropane-l-carboxylate (ACC) synthase Lycopsicon esculentum
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Effects of Enhanced UV-B Radiation on the Activity and Expression of Alternative Oxidase in Red Kidney Bean Leaves 被引量:5
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作者 Ming-Guang Zhao Ying-Gao Liu Li-Xin Zhang Lin Zheng Yu-Rong Bi 《Journal of Integrative Plant Biology》 SCIE CAS CSCD 2007年第9期1320-1326,共7页
An increase in ultraviolet (UV) B radiation on the earth's surface is a feature of current global climate changes. It has been reported that alternative oxidase (AOX) may have a protective role against oxidative ... An increase in ultraviolet (UV) B radiation on the earth's surface is a feature of current global climate changes. It has been reported that alternative oxidase (AOX) may have a protective role against oxidative stress induced by environmental stresses, such as UV-B. To better understand the characteristic tolerance of plants to UV-B radiation, the effects of enhanced UV-B radiation on the activity and expression of AOX in red kidney bean (Phaseolus vulgaris) leaves were investigated in the present study. The results show that the total respiration rate and AOX activity in red kidney bean leaves increased significantly during treatment with enhanced UV-B. However, cytochrome oxidase (COX) activity did not change significantly. The H2O2 content was also markedly increased and reached a maximum of 4.45 mmol·L^-1·g^-1 DW (dry weight) at 24 h of UV-B treatment, before dropping rapidly. Both alternative pathway content and alternative pathway activity were increased in the presence of exogenous H2O2. Immunoblotting analysis with anti-AOX monoclonal antibody revealed that expression of the AOX protein increased in red kidney bean leaves under enhanced UV-B radiation, reaching a peak at 72 h. In addition, AOX expression in red kidney bean leaves was induced by exogenous H2O2. These data indicate that the increase in AOX activity in red kidney bean leaves under enhanced UV-B radiation was mainly due to H2O2-induced AOX expression. 展开更多
关键词 alternative oxidase red kidney bean RESPIRATION uv-b radiation
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Effects of enhanced UV-B radiation on fitness of an alpine species Cerastium glomeratum Thuill 被引量:3
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作者 Ying Wang Nianwei Qiu +2 位作者 Xingan Wang Zongqi Ma Guozhen Du 《Journal of Plant Ecology》 SCIE 2008年第3期197-202,共6页
Aims Information about how species respond to extreme environments,such as high UV-B radiation,is very useful in estimating natural ecosystem structure and functions in alpine areas.Our aim is to examine the effect of... Aims Information about how species respond to extreme environments,such as high UV-B radiation,is very useful in estimating natural ecosystem structure and functions in alpine areas.Our aim is to examine the effect of enhanced UV-B radiation on the fitness of an alpine meadow annual species on Qinghai-Tibet Plateau.Methods Plants of Cerastium glomeratum Thuill.were exposed to ambient(control)or ambient plus supplemental UV-B radiation(enhanced),simulating a 9%ozone depletion over Gannan,China(10253#E,3455#N,2900 m in altitude),up to leaf senescence and fruit maturation.Plant height,flower phenology,biomass allocation and reproductive parameters of the species were measured.Important findings Plant height in C.glomeratum was reduced by enhanced UV-B radiation at early growth stages and compensated with ongoing development.Fruit biomass,aboveground biomass,total biomass and reproductive effort(fruit dry mass/aboveground biomass)were not affected by enhanced UV-B radiation,but a significant increase in root/shoot ratio was found.Enhanced UV-B radiation delayed onset of flowering by 1 day and shortened duration of flowering by 5 days in C.glomeratum.But because of the long period of flowering time(83–88 days),this did not make any significant effect on flower number,seed number,pollination success(number of seeds per fruit)or reproductive success(fruit to flower ratio)in C.glomeratum.Enhanced UV-B radiation had no effect on seed germination and seed mass either.And the high production and low germination rate of the seed might be the strategy of C.glomeratum to survive the extreme environments on alpine meadow.All these results showed that C.glomeratum was tolerant to enhanced UV-B radiation. 展开更多
关键词 uv-b radiation FITNESS FLOWERING REPRODUCTION Qinghai-Tibet Plateau
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Enhanced UV-B radiation during pupal stage reduce body mass and fat content, while increasing deformities, mortality and cell death in female adults of solitary bee Osmia bicornis
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作者 Oskar Wasielewski Tatiana Wojciechowicz +1 位作者 Karol Giejdasz Natraj Krishnan 《Insect Science》 SCIE CAS CSCD 2015年第4期512-520,共9页
The effects of enhanced UV-B radiation on the oogenesis and morpho- anatomical characteristics of the European solitary red mason bee Osmia bicornis L. (Hy- menoptera: Megachilidae) were tested under laboratory con... The effects of enhanced UV-B radiation on the oogenesis and morpho- anatomical characteristics of the European solitary red mason bee Osmia bicornis L. (Hy- menoptera: Megachilidae) were tested under laboratory conditions. Cocooned females in the pupal stage were exposed directly to different doses (0, 9.24, 12.32, and 24.64 kJ/m2/d) of artificial UV-B. Our experiments revealed that enhanced UV-B radiation can reduce body mass and fat body content, cause deformities and increase mortality. Following UV exposure at all 3 different doses, the body mass of bees was all significantly reduced compared to the control, with the highest UV dose causing the largest reduction. Similarly, following UV-B radiation, in treated groups the fat body index decreased and the fat body index was the lowest in the group receiving the highest dose of UV radiation. Mortality and morphological deformities, between untreated and exposed females varied considerably and increased with the dose of UV-B radiation. Morphological deformities were mainly manifested in the wings and mouthparts, and occurred more frequently with an increased dose of UV. Cell death was quantified by the Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay (DNA fragmentation) during early stages of oogenesis of O. bicornis females. The bees, after UV-B exposure exhibited more germarium ceils with fragmented DNA. The TUNEL test indicated that in germarium, low doses of UV-B poorly induced the cell death during early development. However, exposure to moderate UV-B dose increased programmed cell death. In females treated with the highest dose of UV-B the vast majority of germarium cells were TUNEL-positive. 展开更多
关键词 Osmia bicornis ovary development radiation TUNEL uv-b
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Comparative Analysis of Photosynthetic Activity and PSII Protein Profiles of Some Plants Grown under Enhanced Solar UV-B Radiation
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作者 Shanthi Natarajan Savarimuthu Moses Janetta Nithia Govindasamy Kulandaivelu 《Journal of Agricultural Science and Technology(A)》 2018年第5期287-295,共9页
The deleterious effects of ultraviolet B(UV-B)radiation on photosynthesis and photosynthetic proteins of tropical and temperate plants have been studied.Like tropical plants(black gram and green gram),the temperate pl... The deleterious effects of ultraviolet B(UV-B)radiation on photosynthesis and photosynthetic proteins of tropical and temperate plants have been studied.Like tropical plants(black gram and green gram),the temperate plants(carrot and radish)also successfully grown in the tropical region.They were exposed to enhanced UV-B radiation under field condition.Comparative studies show that under enhanced UV-B radiation photosynthetic activity was increased in black gram.In green gram and radish the UV-B radiation slightly enhanced the photosynthetic activity,but it inhibited the photosynthetic activity in carrot.The comparative results showed changes in contents of thylakoid 55,47,43,33,29,27-25,23 and 17 kDa polypeptides that were significantly lowered in UV-B treated carrot plant when compared to other plants.The PSII protein profile results showed a strong correlation between the presence of a membrane polypeptide and photosynthetic activity.In black gram and green gram the UV-B radiation did not produce any significant difference in the PSII polypeptides.As in the case of radish the UV-B radiation increased the accumulation of 33-28 kDa protein and affected expression of the 63 kDa protein.In the case of carrot,severe degradation of 32 kDa and 33 kDa,corresponding to D1 and D2 core proteins of PSII,was observed.It could be concluded that the ability of plants to tolerate increased levels of UV-B radiation,relative to photosynthetic capacity,depends on acclimation processes of the plant in the growing region. 展开更多
关键词 PHOTOSYSTEM II uv-b radiation black GRAM green GRAM CARROT RADISH
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The effect of UV-B radiation enhancement on the interspecific competition between Skeletonema costatum and Heterosigma akashiwo 被引量:7
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作者 XIAOHui TANGXuexi +1 位作者 ZHANGPeiyu CAIHengjiang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2005年第2期77-84,共8页
The responses of the interspecific competition between Skeletonema costatum and Heterosigma akashiwo to UV-B radiation enhancement were studied by the co-culture method. The results showed that Heterosigma akashiwo ex... The responses of the interspecific competition between Skeletonema costatum and Heterosigma akashiwo to UV-B radiation enhancement were studied by the co-culture method. The results showed that Heterosigma akashiwo exhibited inhibition on the growth of Skeletonema costatum, and with the increase of initial inoculation density of Heterosigma akashiwo, heavier inhibition on Skeletonema costatum appeared. Under different inoculation proportions, Heterosigma akashiwo could always be in predominance in competition with Skeletonema costatum. The UV-B radiation treatment could change the competition relationship between Skeletonema costatum and Heterosigma akashiwo, which could increase the competitive dominance of Skeletonema costatum and decrease the competitive dominance of Heterosigma akashiwo. When the inoculation proportions of Heterosigma akashiwo and Skeletonema costatum were H∶S=1∶4 and H∶S=1∶1,Skeletonema costatum was in predominance in this competition; however, Heterosigma akashiwo was in predominance when the inoculation proportion was H∶S=4∶1. 展开更多
关键词 uv-b radiation interspecific competition INHIBITION Skeletonema costatum Heterosigma akashiwo
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Effects of cerium on growth and physiological mechanism in plants under enhanced ultraviolet-B radiation 被引量:6
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作者 LIANG Chan-iuan HUANG Xiao-hua +1 位作者 TAO Wen-yi ZHOU Qing 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2006年第1期125-129,共5页
Effect of cerium (Ce^3+) on the growth, photosynthesis and antioxidant enzyme system in rape seedlings (Brassica juncea L.) exposed to two levels of UV-B radiation (T1: 0.15 W/m^2 and T2:0.35 W/m^2) was studi... Effect of cerium (Ce^3+) on the growth, photosynthesis and antioxidant enzyme system in rape seedlings (Brassica juncea L.) exposed to two levels of UV-B radiation (T1: 0.15 W/m^2 and T2:0.35 W/m^2) was studied by hydroponics under laboratory conditions. After 5 d of UV-B treatment, the aboveground growth indices were obviously decreased by 13.2%-44. 1%(T1) and 21.4%-49.3% (T2), compared to CK, and except active absorption area of roots, the belowground indices by 14.1%-35.6%(T1) and 20.3%-42.6% (T2). For Ce+UV-B treatments, the aboveground and belowground growth indices were decreased respectively by 4.1%-23.6%, 5.2% -23.3%(Ce+T1) and 10.8%-28.4%, 7.0%-27.8%(Ce+T2), lower than those of UV-B treatments. The decrease of growth indices appeared to be the result of changes of physiological processes. Two levels of UV-B radiation induced the decrease in chlorophyll content, net photosynthesis rate, transpiration rate, stomatal conductance and water use efficiency by 11.2%-25.9%(T1) and 20.9%- 56.9%(T2), whereas increase in membrane permeability and activities of antioxidant enzymes including superoxide dismutase(SOD), catalase (CAT) and peroxidase (POD) by 6.9%, 22.8%, 21.5%, 9.5%(T1) and 36.6%, 122.3%, 103.5%, 208.9%(T2), respectively. The reduction of the photosynthetic parameters in Ce+UV-B treatments was lessened to 3.2%-13.8%(Ce+T1) and 4.9%-27.6%(Ce+T2), and the increase of membrane permeability and activities of antioxidant enzymes except POD in the same treatments were lessened to 2.4%, 8.4%, 6.6%(Ce+T1) and 30.1%, 116.7%, 75.4%(Ce+T2). These results indicate that the regulative effect of Ce on photosynthesis and antioxidant enzymatic function is the ecophysiological basis of alleviating the suppression of UV-B radiation on growth of seedlings. Furthermore, the protective effect of Ce on seedlings exposed to TI level of UV-B radiation is superior to T2 level. 展开更多
关键词 cerium(Ce^3+) uv-b radiation RAPE GROWTH PHOTOSYNTHESIS antioxidant enzyme system
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Estimation of enhanced low dose rate sensitivity mechanisms using temperature switching irradiation on gate-controlled lateral PNP transistor 被引量:1
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作者 Xiao-Long Li Wu Lu +7 位作者 Xin Wang Xin Yu Qi Guo Jing Sun Mo-Han Liu Shuai Yao Xin-Yu Wei Cheng-Fa He 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第3期342-350,共9页
The mechanisms occurring when the switched temperature technique is applied,as an accelerated enhanced low dose rate sensitivity(ELDRS)test technique,are investigated in terms of a specially designed gate-controlled l... The mechanisms occurring when the switched temperature technique is applied,as an accelerated enhanced low dose rate sensitivity(ELDRS)test technique,are investigated in terms of a specially designed gate-controlled lateral PNP transistor(GLPNP)that used to extract the interface traps(Nit)and oxide trapped charges(Not).Electrical characteristics in GLPNP transistors induced by ^(60)Co gamma irradiation are measured in situ as a function of total dose,showing that generation of Nit in the oxide is the primary cause of base current variations for the GLPNP.Based on the analysis of the variations of Nit and Not,with switching the temperature,the properties of accelerated protons release and suppressed protons loss play critical roles in determining the increased Nit formation leading to the base current degradation with dose accumulation.Simultaneously the hydrogen cracking mechanisms responsible for additional protons release are related to the neutralization of Not extending enhanced Nit buildup.In this study the switched temperature irradiation has been employed to conservatively estimate the ELDRS of GLPNP,which provides us with a new insight into the test technique for ELDRS. 展开更多
关键词 ionizing radiation damage enhanced low dose rate sensitivity(ELDRS) switched temperature irradiation gate-controlled lateral PNP transistor(GLPNP)
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The Distribution and Morphology Alterations of Microfilaments and Microtubules in Mesophyll Cells and Root-Tip Cells of Wheat Seedlings under Enhanced Ultraviolet-B Radiation
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作者 Limei Gao Yongfeng Li +2 位作者 Aihua Guo Jingru Zhai Rong Han 《American Journal of Plant Sciences》 2014年第22期3423-3431,共9页
The distribution and morphology alterations of microfilaments and microtubules in the mesophyll cells and root-tip cells of wheat seedlings, which had been radiated by enhanced ultraviolet-B (10.08 KJ·m-2·d-... The distribution and morphology alterations of microfilaments and microtubules in the mesophyll cells and root-tip cells of wheat seedlings, which had been radiated by enhanced ultraviolet-B (10.08 KJ·m-2·d-1), were examined through the confocal laser scanning microscope (Model FV1000, Olympus, Japan). Microtubule was labeled with an indirect immunofluorescence staining method, and microfilament was labeled with fluorescein isothiocyanate-phalloidin (FITC-Ph) as probes. The results indicated that microtubules in mesophyll cells, compared with the controls, would be depolymerized significantly, and dispersed randomly showing some spots or short rods in the cytoplasm, under the enhanced UV-B radiation condition. The microtubule bundles tended to be diffused, and the fluorescence intensity of that significantly decreased. The distribution pattern of microfilaments, which usually arranged parallelly in control cells, was broken up by enhanced UV-B radiation. We further investigated the distribution and morphology of microtubules in root-tip cells during every stage of cell division, and found that these aberrant phenomena of microtubules were often associated with abnormal cell division. Our findings suggested that the distribution, morphology and structure of cytoskeleton in mesophyll cells and root-tip cells of wheat seedlings would be affected by enhanced UV-B radiation, which might be related to abnormal cell division caused by enhanced UV-B radiation as an extracellular signal. 展开更多
关键词 Wheat MICROFILAMENT MICROTUBULE enhanced uv-b radiation Confocal Laser Scanning Microscope
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Effects of Exogenous Nitric Oxide on Wheat Exposed to Enhanced Ultraviolet-B Radiation
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作者 Liyan Yang Rong Han Yi Sun 《American Journal of Plant Sciences》 2013年第6期1285-1290,共6页
We explored the use of exogenous nitric oxide (NO) on alleviating effects of UV-B light on winter wheat development. Triticum aestivum L. cv. Linyou 7287 seeds were irradiated with UV-B (10.08 kJ·m–2·d–1) ... We explored the use of exogenous nitric oxide (NO) on alleviating effects of UV-B light on winter wheat development. Triticum aestivum L. cv. Linyou 7287 seeds were irradiated with UV-B (10.08 kJ·m–2·d–1) (enhanced UV-B) and watered with either water or 100 μmol·L–1 SNP solution. Plants were also watered with the SNP alone. The results showed that enhanced UV-B produced negative effects on seedling development. Leaf length decreased and seedling biomass dropped significantly compared with the control. Photochemical efficiency (Fv/Fm) dropped, and chlorophyll and carotenoid content as well as the ATPase activity declined. Content of UV-absorbing compounds and activity of the POD increased compared to the control. Application of the SNP, a NO donor partially protected wheat seedlings exposed to elevated UV-B radiation in that their leaf lengths and biomass accumulation were enhanced compared to the UV-B treatment alone. SNP also improved the contents of chlorophyll, carotenoid and UV-absorbing compounds in leaves. ATPase activity was enhanced but no influence on POD activity. Furthermore, the application of SNP alone showed a favorable effect on seedling growth compared with the control. 展开更多
关键词 NITRIC Oxide SEEDLING Development uv-b radiation WHEAT
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Effects of Cu<sup>2+</sup>on Wheat Seedlings Exposed to Enhanced Ultraviolet-B Radiation
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作者 Liyan Yang Zhaoqing Wang +2 位作者 Yuqi Hou Rong Han Yi Sun 《American Journal of Plant Sciences》 2014年第20期3060-3065,共6页
To explore the wheat seedling development and physiological responses under copper contamination and enhanced ultraviolet-B (UV-B) irradiation, 10 mg·L-1 CuCl2 solution was irrigated to Triticum aestivum L. cv. L... To explore the wheat seedling development and physiological responses under copper contamination and enhanced ultraviolet-B (UV-B) irradiation, 10 mg·L-1 CuCl2 solution was irrigated to Triticum aestivum L. cv. Linyuan 2069 one day after germination with or without ultraviolet-B (10.08 kJ m-2·d-1) light exposure, respectively. The results showed that Cu2+ and UV-B caused various adverse effects on wheat seedling development. Cu2+ hindered root development by significantly reducing root number, while UV-B dwarfed seedling height and decreased the leaf length. Chlorophyll content and activity of ATPase in thylakoid membrane of wheat leaves dropped significantly under enhanced UV-B while the activity of ATPase in plasma membrane of seedling root was significantly decreased in Cu2+ group. Relative electric conductivity of leaves significantly increased in both Cu2+ and UV-B groups, so did the biomass. We also observed that combined Cu2+ and UV-B showed more adverse effects on wheat seedlings than either of them alone except for root growth. 展开更多
关键词 CU2+ SEEDLING Development uv-b radiation WHEAT
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Influences of Different UV-B Radiation Treatments in Short Time on Some Physiological Characteristics of Winter Wheat Seedlings 被引量:14
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作者 张文会 王明卓 +2 位作者 苗秀莲 张玉霞 李宝娟 《Agricultural Science & Technology》 CAS 2009年第5期18-21,共4页
[Objective] studying the influences of different UV-B radiation treatments in short time on some physiological characteristics of winter wheat seedlings was to provide reference for the mechanism of plant response to ... [Objective] studying the influences of different UV-B radiation treatments in short time on some physiological characteristics of winter wheat seedlings was to provide reference for the mechanism of plant response to ultraviolet irradiation in short time. [Method] The winter wheat taken as materials were treated with 15 and 30 pW/cm^2 UV-B radiation, then the physiological indexes such as pigment content and photosynthetic rate were determined. [ Results] The UV-B treatment caused the declines of chlorophyll content, soluble protein content and water content of leaves, besides, dose-effect was existed. The decline of 30 pW/cm^2 treatment was bigger than that of 15 μW/cm^2 treatment. The influences of UV-B radiation on carotenoid content and anthocyanidin content were similar; the change trends were declined firstly then increased. The UVB treatment with two doses restrained the electron transport of PSⅡ, particularly; the inhibitory effect was biggest after treated 2 h, and then this effect was declined in 4, 6 and 8 h, so the dose-effect was existed. The UV-B radiation with two doses restricted photosynthetic rate and the inhibitory effect increased with the increase of treatment time. The high dose treatment caused huge damage to membrane system, while the result of low dose treatment was not obvious. [ Conclusion] UV-B radiation treatment had dose-effect on winter wheat seedlings in short time and the influence of high dose was bigger than that of low dose. With the increase of treatment time, the damage was alleviated; besides, the result was not similar to that of UV-B radiation in long time. 展开更多
关键词 uv-b radiation Winter wheat seedling Physiological index
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Responses of Membrane Lipid Peroxidation and Endogenous Hormones of Soybean Seedlings to UV-B Radiation and Rare Earth 被引量:7
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作者 闫生荣 杨春和 +2 位作者 张跃群 花海蓉 蒋云霞 《Agricultural Science & Technology》 CAS 2009年第6期72-75,90,共5页
[ Objective] The aim was to provide strategies for development of rare earth and control of environmental pollution. [ Method] Responses of membrane lipid peroxidation and endogenous hormones of soybean seedlings to U... [ Objective] The aim was to provide strategies for development of rare earth and control of environmental pollution. [ Method] Responses of membrane lipid peroxidation and endogenous hormones of soybean seedlings to UV-B radiation and rare earth were studied through hydroponics in laboratory. [ Result] The results showed that under irradiation of UV-B( T1-0.15 W/m^2 and T2-0.45 W/m^2), chlorophyll and indole-3-acetic acid(IAA) contents firstly decreased during the stress phase (1 -5 d) and then increased during the restoration phase (6 -9 d) while contents of malonadialdehyde(MDA) and abscisic acid(ABA) gradually increased during the imposition of UV-B radiation (1 -5 d) and subsequently decreased during recovery from UV-B stress (6 -9 d) . With adding of La (III) with the concentration of 20 mg · L^-1 , the decline/dse trend of chlorophyll, IAA, MDA and ABA contents was slowed down during the stress period while the rise/decline speed was accelerated during the recovery period. [ Conclusion] It suggests that the regulation of La ( III ) on membrane lipid peroxidation and endogenous hormones could increase chlorophyll and IAA contents, improve the metabolism of reactive oxygen species ( ROS), inhibit membrane lipid peroxidation, decrease the accumulation amount of ABA and alleviate injury of UV-B radiation to soybean seedlings. Further, the protective potential of La ( III ) was better under low UV-B radiation than under high one. 展开更多
关键词 La III uv-b radiation Soybean seedlings Membrane lipid peroxidation Endogenous hormones
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Effects of UV-B radiation on the growth interaction of Ulva pertusa and Alexandrium tamarense 被引量:10
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作者 CAIHeng-jiang TANGXue-xi ZHANGPei-yu 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2005年第4期605-610,共6页
Enhanced UV-B(280-320 nm) radiation resulting from ozone depletion is one of global environmental problems. Not only marine organisms but also marine ecosystems can be affected by enhanced UV-B radiation. The effects ... Enhanced UV-B(280-320 nm) radiation resulting from ozone depletion is one of global environmental problems. Not only marine organisms but also marine ecosystems can be affected by enhanced UV-B radiation. The effects of UV-B radiation on interaction of macro-algae and micro-algae were investigated using Ulva pertusa Kjellman and Alexandrium tamarense as the materials in this study. The results demonstrated that UV-B radiation could inhibit the growth of Ulva pertusa and Alexandrium tamarense when they were both mono-cultured, and the growth inhibition of algae was more significant with increasing doses of UV-B radiation. Alexandrium tamarense could inhibit the growth of Ulva pertusa in mixed culture, and the growth inhibition was more significant when increasing the initial cell density. However, Ulva pertusa could inhibit the growth of Alexandrium tamarense in early phase and stimulate the growth in latter phase when they were grown in mixed culture. Lower initial cell density(10~2 cell/ml) of Alexandrium tamarense could inhibit the growth of Ulva pertusa under UV-B radiation treatment,however, with the initial cell density increasing(10~3 and 10~4 cell/ml), the growth of Ulva pertusa was stimulated under lower dose of UV-B radiation and inhibited under higher dose of UV-B radiation by Alexandrium tamarense. Compared with that in mixed culture, Ulva pertusa showed more positive inhibition to the growth of Alexandrium tamarense under UV-B radiation treatment. 展开更多
关键词 uv-b radiation mono-culture mixed culture Ulva pertusa Alexandrium tamarense GROWTH
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Effects of lanthanum(Ⅲ) on nitrogen metabolism of soybean seedlings under elevated UV-B radiation 被引量:9
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作者 CAO Rui HUANG Xiao-hua +1 位作者 ZHOU Qing CHENG Xiao-ying 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2007年第11期1361-1366,共6页
The hydroponic culture experiments of soybean bean seedlings were conducted to investigate the effect of lanthanum (La) on nitrogen metabolism under two different levels of elevated UV-B radiation (UV-B, 280-320 nm... The hydroponic culture experiments of soybean bean seedlings were conducted to investigate the effect of lanthanum (La) on nitrogen metabolism under two different levels of elevated UV-B radiation (UV-B, 280-320 nm). The whole process of nitrogen metabolism involves uptake and transport of nitrate, nitrate assimilation, ammonium assimilation, amino acid biosynthesis, and protein synthesis. Compared with the control, UV-B radiation with the intensity of low level 0.15 W/m^2 and high level 0.45 W/m^2 significantly affected the whole nitrogen metabolism in soybean seedlings (p 〈 0.05). It restricted uptake and transport of NO3^-, inhibited activity of some key nitrogen-metabolism-related enzymes, such as: nitrate reductase (NR) to the nitrate reduction, glutamine systhetase (GS) and glutamine synthase (GOGAT) to the ammonia assimilation, while it increased the content of free amino acids and decreased that of soluble protein as well. The damage effect of high level of UV-B radiation on nitrogen metabolism was greater than that of low level. And UV-B radiation promoted the activity of the anti-adversity enzyme glutamate dehydrogenase (GDH), which reduced the toxicity of excess ammonia in plant. After pretreatment with the optimum concentration of La (20 mg/L), La could increase the activity of NR, GS, GOGAT, and GDH, and ammonia assimilation, but decrease nitrate and ammonia accumulation. In conclusion, La could relieve the damage effect of UV-B radiation on plant by regulating nitrogen metabolism process, and its alleviating effect under low level was better than that under the high one. 展开更多
关键词 lanthanum(Ⅲ) uv-b radiation soybean seedlings nitrogen metabolism alleviating effect
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Effects of UV-B radiation and different light repair conditions on the early development of the tetraspores of Chondrus ocellatus Holm 被引量:1
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作者 JU Qing TANG Xuexi +2 位作者 ZHAO Xiaowei REN Xiuqun LI Yunfei 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2011年第3期100-111,共12页
The effects of exposure to UV-B radiation, 280-315 nm, and dark or dark repair conditions on the early development of Chondrus ocellatus Holm collected from Qingdao coast were studied under the laboratory condition. A... The effects of exposure to UV-B radiation, 280-315 nm, and dark or dark repair conditions on the early development of Chondrus ocellatus Holm collected from Qingdao coast were studied under the laboratory condition. After being exposed to different doses [0, 36, 72, 108, 144 and 180 J/(m2.d)] of UV-B radiation, one treatment of tetraspores were put back to normal culture condition (PAR), the other treatment were put into dark condition to repair for 2 h. During the cultivation, the diameter of the tetraspores were recorded every 4 d till the 50th day when vertical branches formed in all treatments. Then at the 50th day, CPDs, phycoerythrin, chlorophyll a and MAAs (Palythine and asterina-330) were measured. The results showed that low doses UV-B radiation could significantly accelerate the growth rate of the rate reduced gradually with UV-B radiation keep on tetraspores of C. ocellatus and the growth increasing. The variation trend of both the phycoerythrin and chlorophyll a concentration reduced significantly (P 〈0.05) once given the UV- B radiation. Under UV-B stress, the CPDs were induced, and the concentrations of CPDs were significant low in dark repair groups. The data of MAAs analyzed by LC/MS in the tetraspores of C. ocellatus suggested that there were two MAAs formed (palythine and asterina-330) after UV-B radiation induced, and low dose of UV-B irradiation could significantly induced the concentration of MAAs. From the growth and development state of the tetraspores, negative effects of UV-B radiation on the dark repair groups were more serious than PAR. 展开更多
关键词 C. ocellatus uv-b radiation enhancement PAR dark repair condition MAAS
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