Hg2+胁迫对小麦幼苗POD、CAT和SOD同工酶的影响（英文）

[Objective] This work was aimed to explore the mechanism of Hg2+ toxicity on plants.[Method]Activities of peroxidase(POD),catalase(CAT)and superoxide dismutase(SOD)were investigated in wheat(Triticum aestivum L.)seedlings under Hg2+ stress at different concentrations.[Result]① There were no obvious effects on the growth of seedlings when the concentration of Hg2+ was lower than 0.10 mmol/L.However,toxic effects on the growth of seedling were observed when the concentration of Hg2+ was higher than 0.10 mmol/L.② Different tissues showed different resistant ability in response to Hg2+ stress.The leaves and roots of wheat seedlings were more insensitive to Hg2+ toxicity.③ CAT was more sensitive to Hg2+ stress compared to POD and SOD.[Conclusion]The toxic effect was related to the concentration of Hg2+(0.10 mmol/L).The higher concentration of Hg2+ could affect the expression of POD,CAT,and SOD isozymes in the leaves,roots of wheat seedlings and germinated seeds,which further affect the normal metabolism of membrane lipid and inhibit the growth of wheat seedlings at last.     

Effects of Phenolic Acids on Growth and Activities of Membrane Protective Enzymes of Cucumber Seedlings

Two phenolic acids P-hydroxy benzoic acid and cinnamic acid were designated as four concentrations (0, 50μmol/L, 100μmol/L, 150μmol/L) to investigate the effects of phenoic acids on the growth and the activities of membrane protective enzymes of cucumber seedlings. The results showed that both phenolic acids inhibited the seedlings growth. The inhibitory effects were increased with the concentration of phenolic acids increasing and the time of treatment prolonging. Seedlings treated with A150 (P-hydroxy benzoic acid, 150μmol/L), B50 (cinnamic acid, 50 μmol/L), B100 (cinnamic acid,100μmol/L), B150 (cinnamic acid, 150μmol/L) showed significantly shorter in plant height , smaller in leaf area. and lighter in fresh weight. The inhibitory effect of cinnamic acid was comparatively stronger than that of P-hydroxy benzoic acid. For protective enzymes system, compared to control, the POD activity increased at all concentrations of P-hydroxy benzoic acid during the treatment but increased at first then decreased before increased again at last at all concentrations of cinnamic acid . In the case of CAT, its activity increased at first, then decreased, and increased again at lower concentrations of phenolic acids. However, at higher concentrations the activities decreased at first, then increased a little, decreased continuously at last. In addition, the treatments of phenolic acids led to an increase then a decreaseof SOD activity and an increase of MDA content in the seedlings. All above indicated the accumulating of free radicalsand destruction of protective enzymes at higher concentrations of phenolic acids.     

Introduction of T-DNA into Watermelon by Stigma Smeared Method and Its Molecular Marker Research

[Objective]The aim was to introduce T-DNA into watermelon for its molecular marker research.[Method]Based on the method of foreign DNA introduced to Arabidopsis thaliana via dipping flowers,the stigma smear was used to transfer T-DNA into watermelon and its molecular marker research was carried out.[Result]The ideal transformed species was ZXG01078 for the highest fruit setting rate and the most deviant seedlings.The best concentration of kanamycin for treating watermelon seeds was 500-700 mg/L with differences among the species.The best position was spire leaf or young leaf and the best concentration of kanamycin for treating the watermelon leaf was 4 000-8 000 mg/L with no significant difference among species.The steadily variation appearing of growing pointless and conjoined twin seedlings indicated that the normal growth had been interfered by foreign DNA in the progeny.[Conclusion]This study had provided basis for the further research on watermelon.     

Genotypic Difference in the Responses of Seedling Growth and Cd Toxicity in Rice （Oryza sativa L.）

The experiment was carried out to study the genotypic difference in the responses of seed germination, growth and physiological characters of rice seedlings to Cd toxicity. The result showed that the germination was slightly stimulated under low Cd concentration （0.01-1.5 mM Cd）, while severely depressed under higher Cd concentration （2.0 mM）. Rice seedlings exposed to 0.01 mM Cd showed slight increases in plant height, root volume, biomass and chlorophyll concentration. These parameters were significantly reduced when Cd level in the medium was increased to 0.5 mM, and meanwhile corresponding increase in superoxide dismutase （SOD） and peroxidase （POD） activities, and MDA （malondialdehyde） content was observed. However, SOD and POD activities declined when plants were exposed to 1 mM Cd when compared with those under 0.5 mM Cd. Cadmium addition lowered Fe, Cu and Mn concentrations in roots and shoots. There was significant genotypic difference in the response of these parameters to Cd stress. Under Cd stress, Xiushui 110 had the least inhibition of growth and increase in MDA content, higher shoot Cd concentration, and greatest increase in POD and SOD activities, indicating its higher tolerance to Cd toxicity, while Bing 9914 had the greatest reduction of growth, and Zn, Cu, Fe, and Mn contents, but greatest increase in MDA content, and least increase in activities of antioxidative enzymes, indicating its sensitivity to Cd toxicity.     

Effects of Wounding and Exogenous Jasmonic Acid on the Peroxidation of Membrane Lipid in Pea Seedlings Leaves

The changes of malondialdehyde （MDA）, H2O2, and O2^7 content, or the activities of superoxide dismutase （SOD）, catalase （CAT）, ascrobate peroxidase （APX）, peroxidase （POD）, phenylalanine ammonia lyase （PAL）, and polyphenol oxidase （PPO） in pea seedlings （Pisum sativum L.） under wounding and treatment of exogenous jasmonic acid （JA） were investigated. The results showed that the activities of both phenylalanine ammonia lyase （PAL） and polyphenol oxidase （PPO） were significantly increased by wounding and application of JA. The metabolism of reaction oxidative species （ROS） was enhanced, especially O2^7 and H2O2 appeared to rapidly increase. The activities of antioxidant enzymes such as SOD, CAT, APX and POD were also increased. Treatment of JA of 1 or 10 μmol L^-1 could effectively induce plant defense response, and thus decrease the peroxidation of cell membrane lipid. However, high concentration of JA （100 μmol L^-1） resulted in unbalance of metabolism of ROS and promoted the peroxidation of cell membrane lipid. We thus suggested that JA, under the suitable concentration, could induce defense response of pea seedlings to wounding.     

Relationship Between Net Photosynthetic Rate of Cassava SC205 and Its Physio-ecological Factors

[Objective] The aim was to measure photosynthetic characters of SC 205, a cassava cultivar, and explore the relationships of the net photosynthetic rate(Pn) with physiological and ecological factors. [Method] The diurnal variations of photosynthesis in leaves of SC205 were studied by LICOR-6400 portable photosynthesis system, and the relationships of the net photosynthetic rate(Pn) with physiological and ecological factors were studied by simple correlation analysis and path analysis. [Result] The curve of diurnal variation of Pn showed single peak at 10:00 am at 24.07 μ mol CO2m2/s, without showing midday depression; the diurnal changes of stomatal conductance(Gs), transpiration rate(Tr), leaf temperature(Tl), air temperature(Ta) and photosynthetic active radiation(PAR) all showed single peak curves, and there were positive relationships of Pn with Gs, Tr, Tl, Ta and PAR. The diurnal variations of intercellular CO2concentration(Ci), atmospheric CO2concentration(Ca), relative humidity(RH) showed in a U-shape curve. There were highly significant positive correlation of Pn with Gs and PAR; the diurnal variation of Pn had highly significant negative correlations with Ci and Ca. The direct impact of physiological factors on Pn was as follows: CiGsTlTr, and the direct impact of ecological factors was RH PAR Ca Ta. [Conclusion] The research showed that Ci, Gs and Tr play very important roles in the changes of Pn among the physiological factors, and PAR and Ca affect the changes of Pn among the ecological factors.     

土壤镉污染对大蒜生理生化指标的影响(英文)

[Objective] The experiment aimed to study the effects of cadmium pollution in soil on physiological and biochemical index of Allium sativum L. and provided reference for the recovery of cadmium pollution in soil. [Method]By setting eleven Cd concentrations from 0.21 to 500 mg/kg in soil and the pot test, ecological corresponding mechanism of plant height, chlorophyll (Chl) content, catalase (CAT) activity and malondialdehyde (MDA) of Allium sativum L. was analyzed. [Result] The plant height had a strong tolerance to cadmium pollution in soil, while the total chlorophyll content and chlorophyll a content had no significant difference compared with control treatment, except Cd concentration was 500 mg/kg. The high Cd concentration would increase the damage to membrane of Allium sativum L. however with the regulation of physiological mechanism, the damage was gradually decreased.[Conclusion] Allium sativum L. had strong eco-physiological adaptability to Cd contaminated soil and it had potential for recovering Cd contaminated soil.     

Effects of Exogenous Cinnamic Acids on the Growth and Physiological Characteristics of Cucumber Seedlings

In order to study the effects of exogenous cinnamic acids on plant growth, contents of photosynthetic pigment, root activities and ATPase activities of root membrane at cucumber seedling stage, the seedlings of Shandong Mici cucumber were tested. The results showed that seedlings growth, contents of photosynthetic pigment, root activities and ATPase activities of root membrane were inhibited by cinnamic acids. The growth and root activities of seedlings were significantly （P〈0.05） lower in the soil amended with 100 mg kg^-1 cinnamic acids compared to the control. The contents of chlorophyll a, chlorophyll a＋b and carotenoid of seedlings significantly （P〈0.05） decreased in the soil amended with 200 mg kg^-1 cinnamic acids, whereas ATPase activities exhibited a higher sensitivity and greatly decreased in the soil amended with 50 mg kg^-1 cinnamic acids. These results suggested that cinnamic acids could induce a stress condition, and the stress intensities increased with enhanced cinnamic acid concentration.     

Alleviation of Al Toxicity in Barley by Addition of Calcium

The potential mechanism by which Ca alleviates Al toxicity was investigated in barley seedlings. It was found that 100 Al-alone treatment inhibited barley plant growth and thereby reduced shoot height and root length, and dry weights of root, shoot and leaf; promoted Al accumulation but inhibited Ca absorption in plant tissues; and induced an increase in the activities of superoxide dismutase （SOD）, catalase （CAT）, and peroxidase （POD） and in the level of lipid peroxidation （MDA content） in leaves. Except for the increase in Ca concentration in plant tissues, treatment with 0.5 mM Ca in the absence of Al had less effect on the above-mentioned parameters, compared with the control. Addition of Ca efficiently reduced Al toxicity, which is reflected by the promotion of plant growth, reduction in Al concentration and MDA content, increase in Ca concentration and in SOD, POD, and CAT activities compared with the Al-alone-treatment; with increase in Ca level （3.0 raM）, the ameliorative effect became more dominant. This indicated that the alleviation of aluminum toxicity in barley seedlings with Ca supplementation could be associated with less absorption of Al and the enhancement of the protective ability of the cell because of increased activity of the antioxidative enzyme.     

生长素介导下三唑醇在大豆植株内的传导性(英文)

[Objective] This study was to investigate the mobility of IAA-triadimenol and NAA-triadimenol in soybean seedlings. [Method] Soybean seedlings were treated by spraying the solution of conjugated compounds onto their leaves; and chromatography was employed to measure the contents of IAA-triadimenol and NAA-triadimenol in different parts of these soybean seedlings, through which to represent the mobility of the conjugates. [Result] Both the triadimenol and NAA-triadimenol could not transport basipetally; whereas IAA-triademenol was ambimobile. When sprayed with 0.5 mmol/L IAA-triadimenol, as much as 1.87 μg/(g·FW) IAA-triadimenol was detected in the roots of soybean seedlings 12 h later, which was higher than that in the stem [0.68 μg/(g·FW)]; while that decreased to 0.80 μg/(g·FW) in the seedlings sprayed with 0.5 mmol/L IAA-triadimenol and the same concentration of IAA. [Conclusion] IAA moiety of the conjugate could enhance the transport and accumulation of the fungicide towards the root via the IAA carriers.     

外源牛磺酸处理对枸杞幼苗生理特性的影响

[目的]探索牛磺酸与枸杞幼苗生理活动之间的关系。[方法]采用牛磺酸溶液处理枸杞幼苗,处理浓度分别为0（CK）、10、100、500、1000、5003mg／L,测定牛磺酸对枸杞幼苗光合速率、细胞膜相对透性和膜脂过氧化产物丙二醛（MDA）含量、保护酶超氧化物歧化酶（SOD）、过氧化物酶（POD）活性的影响。[结果]适宜浓度的牛磺酸处理可在一定程度上提高叶片的光合效率,使SOD、POD的活性增加,降低细胞膜相对透性和膜脂过氧化产物MDA的含量,并且最适处理浓度约为500mg／L.[结论]适宜浓度的牛磺酸对枸杞幼苗细胞膜有一定的保护作用。     

铜对空心菜光合作用及保护酶活性的影响

为了解铜对空心菜光合作用及保护酶活性的影响。以空心菜为供试材料,设计施铜浓度0 mg/kg、30mg/kg、80 mg/kg、100 mg/kg、200 mg/kg、400 mg/kg、600 mg/kg、和1 000 mg/kg 8个处理,采用土培方式分析重金属铜对空心菜干重、净光合速率、气孔导度、胞间CO2浓度、蒸腾速率、SOD活性、POD活性的影响。结果表明:空心菜叶片净光合速率、气孔导度和蒸腾速率随施铜浓度的升高而上升,当施铜浓度达到100 mg/kg时,开始下降;施铜浓度为200 mg/kg、400 mg/kg时,空心菜叶片SOD活性相比对照显著升高,而当施铜浓度为600 mg/kg时,SOD活性降低;施铜浓度大于200 mg/kg时,空心菜叶片POD活性相比对照显著升高,说明当土壤中施铜浓度超过200mg/kg时,会对空心菜生长产生不良影响。因此,施较低浓度的铜(≤80 mg/kg)对空心菜生长影响不显著,施较高浓度的铜(≥100 mg/kg)对空心菜的生长有抑制作用。     

镍胁迫对玉米苗根系生长及膜保护系统的影响

[目的]研究镍（Ni2＋）胁迫对玉米（Zea mays L.）根系生长及膜保护系统的影响。[方法]以玉米为材料,研究了不同浓度Ni2＋胁迫对玉米幼苗根系生长、根系活力及根系中超氧化物歧化酶（SOD）、过氧化物酶（POD）活性和丙二醛（MDA）含量的影响。[结果]不同浓度Ni2＋处理对玉米幼苗根系具有低浓度的促进效应和高浓度的抑制效应,且随着浓度的增加抑制效应逐渐增强。根系长度、鲜重、根系活力、SOD活性、POD活性、MDA含量在3个处理阶段（10、30、30 d）变化趋于相同;随着玉米幼苗的生长,各项指标变化更加明显。根系活力在Ni2＋浓度为50 mg/kg（土）时最强,随着Ni2＋浓度的升高而逐渐减弱;根系保护酶系统中SOD和POD活性随着Ni2＋浓度的增加而呈现先升高后下降的变化趋势,在Ni2＋浓度为50 mg/kg（土）时出现峰值;根系细胞内MDA含量在低Ni2＋浓度处理下增幅较小,Ni2＋浓度在100～800 mg/kg（土）时增加显著。[结论]Ni2＋浓度低于50 mg/kg（土）时对玉米幼苗期根系的生长有促进作用,而超过该浓度则表现为抑制作用,Ni2＋浓度越高,抑制作用越明显。     

外源NO调控红松幼苗光合作用与抗氧化酶活性的浓度效应

[目的]探讨不同浓度外源NO对红松针叶光合色素和抗氧化酶活性的影响。[方法]以3年生红松针叶为试验材料,测定喷施不同浓度外源NO供体硝普钠溶液(0、0.01、0.10、0.50和1.00 mmol/L SNP)处理下其光合色素含量、抗氧化酶活性、丙二醛(MDA)含量和过氧化氢(H_2O_2)含量等生理指标。[结果]净光合速率(Pn)、蒸腾速率(Tr)和呼吸速率(Rd)会随着SNP浓度增加而增加,分别在SNP喷施0.10和0.50 mmol/L时达到最大值;喷施0.01 mmol/L SNP有效提高了气孔导度(Gs)、胞间CO_2浓度(Ci)、光合色素含量、过氧化氢酶(CAT)活性、过氧化物酶(POD)活性,而超氧化物歧化酶(SOD)活性、H_2O_2含量和MDA含量在喷施外源NO时显著降低。[结论]施加适量浓度外源NO会显著增加光合参数、光合色素含量、CAT活性、抗坏血酸过氧化物酶(APX)活性、POD活性,但施加外源NO降低了SOD活性、H_2O_2含量、MDA含量,从而降低了细胞膜脂过氧化程度,减轻了红松幼苗受到的伤害。     

蚕豆幼苗光合特性及抗氧化酶对Cs~+胁迫的响应

为研究蚕豆的光合特性及抗氧化酶在铯(Cs~+)胁迫下的响应特征,用浓度为0～200 mg/L Cs~+溶液浇灌盆栽蚕豆,模拟~(137)Cs随雨水沉降造成的土壤放射性污染,测定不同浓度Cs~+溶液浇灌下蚕豆幼苗的光合特性及抗氧化酶活性等的变化。结果显示,蚕豆叶片叶绿素含量随Cs~+浓度的增加呈现先增加后下降的趋势,低浓度Cs~+(25 mg/L)处理净光合速率(Pn)有所增加,高浓度(200 mg/L)处理Pn略有下降;蒸腾速率(E)、气孔导度(Gs)、胞间CO_2浓度(Ci)在一定程度上显著增加;蚕豆叶片的原初光能转化效率(Fv/Fm)、PSⅡ实际光化学效率(ΦPSⅡ)、光化学淬灭系数(qP)、电子传递速率(ETR)等无显著性变化,非光化学淬灭系数(qNP)在50 mg/L和200 mg/L处理下显著升高,非光化学耗散增强;过氧化物酶(peroxidase,POD)和抗坏血酸(ascorbate peroxidase,APX)活性显著降低,POD和APX对Cs~+胁迫的响应要强于超氧化物歧化酶(superoxide dismutase,SOD);相关性分析表明,蚕豆的Pn和POD、APX活性与其体内Cs~+富集量呈一定的负相关关系。结果表明蚕豆对Cs~+胁迫的耐受性强,有较强的Cs~+富集能力,且主要蓄积在根中,安全性增强,在土壤铯污染修复中具有较大的应用潜力。     

荠菜幼苗对汞胁迫的生理响应

[目的]探讨荠菜幼苗对汞胁迫的生理响应。[方法]采用砂培法研究了不同浓度Hg2＋胁迫下荠菜幼苗叶中叶绿素含量以及SOD和POD抗氧化酶活性的变化。[结果]幼苗叶绿素含量在低浓度Hg2＋（≤1.0 mg/L）胁迫时略有增加,而在高浓度Hg2＋胁迫（20.0mg/L）时降低。丙二醛含量则随Hg2＋胁迫浓度的增加而增加。SOD和POD活性均随着Hg2＋浓度的增加呈先上升后下降的趋势,其中当Hg2＋浓度为1.0 mg/L时SOD和POD活性分别为对照的158.0%和161.0%,而在当Hg2＋浓度为20.0 mg/L时分别为对照的27.1%和16.7%,表明酶活性在一定浓度的Hg2＋胁迫下能作出应激反应。[结论]为荠菜驯化和栽培提供了理论依据。     

NaCI胁迫对无柄小叶榕光合作用和抗氧化酶活性的影响

以无柄小叶榕幼苗为研究材料,研究了不同NaCl浓度处理对无柄小叶榕气体交换、叶绿素荧光和抗氧化酶活性的影响。结果表明：在低浓度NaC[胁迫（50mmol／L）处理7d后,无柄小叶榕净光合速率（Pn）、气孔导度（G1）和胞间CO,浓度（C1）分别下降24％、31％和30％。低浓度NaCI处理并没有引起光化学猝灭（qP）和...     

外源ABA、Put和BR对亚适温条件下番茄幼苗叶片保护酶活性的影响

【研究目的】笔者研究了亚适温下不同浓度的脱落酸、腐胺、油菜素内脂对冷敏品种番茄“中蔬6号”幼苗保护酶活性的影响。【方法】选用不同浓度ABA、Put、BR溶液喷散番茄幼苗,清水处理作对照,每5d喷一次,共2次。然后在光照培养箱中模拟亚适温环境对番茄幼苗进行处理。【结果】亚适温下,番茄幼苗的MDA含量持续升高、SOD活性先升高后降低。对番茄幼苗进行适宜浓度的ABA、Put、和BR预处理,能够提高亚适温下番茄幼苗的SOD活性,降低MDA含量,有效地缓解亚适温引起的番茄幼苗叶片细胞的膜脂过氧化。降低MDA含量的最适浓度ABA为0.2mmol/L,Put为0.5mmol/L,BR为0.01mg/L;提高SOD活性的最适浓度ABA0.2mmol/L,Put为1.0mmol/L,BR为0.01mg/L。与对照相比,MDA含量分别降低47.7%、43.2%、42.2%,SOD活性分别提高29.2%、17.4%、28.6%;【结论】亚适温对番茄幼苗叶片细胞膜造成了伤害,膜脂过氧化产物MDA含量升高,SOD含量下降;喷施适宜浓度的A-BA、Put、BR可以降低MDA含量,使SOD活性增加,减轻亚适温对番茄幼苗的伤害。     

ABA对盐胁迫下番茄幼苗生理特性的影响

[目的]研究外源ABA对盐胁迫下番茄幼苗生理特性的影响。[方法]以番茄幼苗为材料,研究外源ABA对100mmol/LNaCl盐胁迫下番茄幼苗氧化损伤和保护酶活性的影响。[结果]0.05mmol/LABA处理能明显缓解100mmol/LNaCl盐胁迫伤害,使叶片MDA含量降低34.01%,细胞膜透性降低42.42%,SOD、POD和CAT活性分别提高30.99%,45.69%和30.29%。较低浓度（0.01mmol/L）和较高浓度（0.10、0.15mmol/L）ABA处理的有效作用整体上明显降低。[结论]0.05mmol/LABA处理能明显缓解盐胁迫对番茄幼苗的氧化损伤,提高膜保护酶活性,增强幼苗的抗盐胁迫能力。ABA的作用具浓度效应。     

高温和干旱胁迫对杨树幼苗光合性能和抗氧化酶系统的影响

采用室内模拟试验,研究了高温、干旱单一或复合胁迫对南林895杨(PopulusבNanlin-895’)幼苗光合特性、叶绿素荧光、抗氧化酶活性的影响。结果表明:随着胁迫时间的延长,高温、干旱单因子和复合胁迫使杨树幼苗净光合速率(P_n)、气孔导度(G_s)、蒸腾速率(T_r)、最大荧光(F_m)、PSII最大原初光化学量子效率(F_v/F_m)下降、初始荧光(Fo)升高,中度干旱胁迫使胞间CO_2摩尔分数(Ci)、水分利用效率(WUE)先降后升,超氧化物歧化酶(SOD)、过氧化物酶(POD)活性先升后降,P_n主要受气孔和非气孔因素共同限制;重度高温、重度干旱和复合胁迫末期SOD、POD活性下降显著,P_n主要受非气孔因素限制。复合胁迫对P_n、T_r具有叠加效应。复合胁迫对P_n、G_s、Ci、T_r、F_v/F_m、SOD的胁迫效应大于单一胁迫;杨树幼苗在高温和干旱复合胁迫条件下受害最严重。