铝钙复合作用对杉木幼苗抗氧化能力的影响

采用水培法研究了铝钙复合作用对1年生杉木幼苗叶片丙二醛(MDA)含量和超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、过氧化物酶(POD)3种抗氧化物酶活性的影响。结果表明:高铝浓度(1.5 mmol·L~(-1))胁迫下,增加钙离子浓度可以明显降低杉木幼苗叶片MDA含量,增强SOD、CAT、POD活性,且增强效应随培养时间的延长而愈加明显;在高钙浓度(4.5 mmol·L~(-1))处理下,随着铝浓度的上升,幼苗叶片MDA含量升高,SOD、CAT活性下降,而POD活性变化却不明显。高铝浓度胁迫下杉木幼苗受毒害程度较大,而在高钙浓度下铝毒对杉木幼苗影响相对减弱;钙离子对杉木幼苗铝毒具有一定程度的缓解作用。     

铜胁迫对弯囊苔草（Ｃａｒｅｘ ｄｉｓｐａｌａｔａ）生长和生理特性的影响

用水培方法研究了弯囊苔草在不同Cu2+浓度(1、5、25mg·L-1)胁迫下的生长特性和部分生理生化指标的变化。结果表明,不同Cu2+浓度胁迫下,弯囊苔草正常生长,但其生长特性表现出高浓度抑制的相关性,高浓度下没有新生根。弯囊苔草叶片3种抗氧化酶活性都随胁迫时间的延长呈先上升再下降趋势。SOD在处理的第4d达到峰值,且活性一直显著高于对照(P<0.05),3种Cu2+浓度处理下的峰值大小顺序为5mg·L-1>25mg·L-1>1mg·L-1。POD和CAT活性在处理第7d达到峰值,POD活性峰值大小顺序为5mg·L-1>1mg·L-1>25mg·L-1;CAT活性峰值大小顺序为25mg·L-1>5mg·L-1>1mg·L-1。丙二醛(MDA)和可溶性糖含量都是随着胁迫时间的延长而上升,处理结束时的丙二醛(MDA)(r=0.9880)和可溶性糖含量(r=0.9512)与Cu2+浓度表现出正相关性。脯氨酸(Pro)含量随胁迫时间的延长也呈先上升后下降趋势,1mg·L-1和5mg·L-1Cu2+浓度处理下脯氨酸(Pro)含量在处理第4d达到最大值,25mg·L-1高浓度处理下脯氨酸(Pro)含量在处理第7d达到最大...     

Effect of ginger supplementation on developmental toxicity induced by fenitrothion insecticide and/or lead in albino rats

Evaluation of the antioxidant and antiteratogenic role of ginger Zingiber officinale polyphenols against the toxicity induced by fenitrothion and/or lead in female albino rats were investigated. Adult virgin females were divided into 8 groups and were orally treated as follow: control (C), 1% w/w of ginger (G), 120 μg/animal lead as lead acetate (L), 10 mg/kg of fenitrothion (F), lead (120 μg/animal) fenitrothion (10 mg/kg) (LF), ginger (1%w/w) + fenitrothion (10 mg/kg) (GF), ginger (1%w/w) + lead (120 μg/animal) (GL), ginger (1%w/w) + lead (120 μg/animal) + fenitrothion (10 mg/kg) (GLF). Treatments were expanded for 28 days before pregnancy and during gestation period from zero to 6th day. Blood samples were taken at the day 20th of gestation and animals were sacrificed to investigate the effect of tested substances on dams and development of their fetuses. Inhibition in AchE in (F) and (LF) groups and elevation in plasma AchE in (L) groups were observed. Elevation in oxidative stress biomarker malondialdehyde (MDA) was recorded in all intoxicated groups concomitants with reduction in total reduced glutathione (GSH) and reduction in the activity of glutathione S-transferase (GST). Elevation in liver function biomarkers alanin amintransferase (ALT) and aspartate aminotransferase (AST) and reduction in plasma total protein and albumin were recorded in (F), (L) and (LF). Supplementation with ginger in diet attenuates the alteration in MDA, GSH, GST, ALT and AST, however, it failed to counteract the effect of F, L and LF on AchE, total protein and albumin. Significant alterations in maternal toxicity were recorded in (GF, GL, LF and GLF) compared with control group. Also, parameters of embryotoxicity and fetotoxicity indicated significant decrease in litter number that observed in F and L and the number of dead fetus/dam and litters number increased in L group. Supplementation with ginger decreased each of the number of died fetus, growth retardation and fetal length, while, it increased fetal weight. As regards to, teratological aspects, the percentage of skeletal malformations and visceral anomalies were observed in all feti obtained from treated groups with different percentages. Supplementation with ginger slightly attenuates the developmental toxicity of fenitrothion and/or lead.     

高羊茅和钝叶草对土壤缓慢水分胁迫的响应差异

以草坪草高羊茅(Festuca arundinacea)和钝叶草(Stenotaphrum secundatum)为材料,研究了盆栽条件下2种草的叶片和根系的质膜透性、抗氧化酶活性及膜脂过氧化产物丙二醛(MDA)含量等生理性状对土壤缓慢干旱胁迫(生长60 d,覆盖率达95%以上后断水处理)的响应.结果表明,在干旱胁迫下,高羊茅的土壤含水量下降比钝叶草更为迅速,相对电导率和MDA含量的增加幅度也相应高于钝叶草.SOD、POD、CAT 3种抗氧化酶活性均表现出先升后降的变化,高羊茅抗氧化酶活性的下降时期出现的比钝叶草早.在相同程度的干旱胁迫下,由于植物失水速度差异所引起的植物细胞受伤害程度、体内膜脂过氧化物含量及活性氧保护酶活性出现下降时期上的差异可能是2种草坪草抗旱性机制差异的一个重要原因.     

盐胁迫对海姆维斯蒂枸子生长及丙二醛和脯氨酸含量的影响

采用盆栽试验法,设置2.16（CK）、3.16、4.16、5.16、6.16和7.16mg·L^-1浓度的NaCl溶液处理,研究了海姆维斯蒂枸子（Cotoneaster hjelmqvistii）的耐盐能力。试验采用随机区组设计,3次重复。对生长量和叶片中游离脯氨酸及丙二醛含量等指标进行了测定分析。结果表明：盐胁迫下,随着盐浓度的升高,叶片中游离脯氨酸含量表现为先上升后下降;而丙二醛则随盐浓度的升高基本保持上升趋势;3.16mg·L^-1处理与对照相比,新梢生长量的差异不显著,在高于3.16mg·L^-1的盐处理下,随着盐胁迫程度的加深,新梢生长量逐渐降低。根据盆栽试验结果及其在盐碱地中的生长表现,认为海姆维斯蒂枸子是一种具有较好耐盐性的木本地被植物,在含盐量4.00mg·L^-1以下的士壤中可正常生长。     

NaCl和温度双重胁迫对黑麦草幼苗叶绿素及相关酶活性的影响研究

控制黑麦草萌发时的NaCl浓度和温度,研究其幼苗叶片中的抗氧化酶活性、丙二醛和叶绿素含量的变化.研究发现,所测指标对温度和NaCl的综合反应差异很大.适量NaCl对所测指标均有一定促进作用;不同温度条件下叶绿素含量、SOD酶、POD酶和CAT酶的活性随NaCl浓度增大均表现为先升高后降低的趋势.但各指标对温度反应的差异却很大,20℃时黑麦草的叶绿素含量最高,SOD酶与CAT酶的活性在相同NaCl浓度下,均为10℃＞20℃＞30℃.POD酶在低NaCl浓度时,其活性为30℃＞20℃＞10℃,但NaCl浓度大于等于0.9%时,30℃的POD酶活性受抑明显,其活性最低.指示细胞受氧化损伤程度的MDA含量随温度和NaCl浓度的升高而增大.     

Chemical model for phosphine‐induced lipid peroxidation

Phosphine (PH₃) from hydrolysis of metal phosphides is highly toxic and is important for control of stored‐product insect pests (AlP, Mg₃P₂) and rodents (Zn₃P₂). This fumigant inhibits respiration and induces lipid peroxidation in insects and mammals. PH₃ (from Mg₃P₂) and H₂O₂, acting for 15 min in phosphate buffer (pH 7.4), oxidized cod liver oil (high in unsaturated lipids) to malondialdehyde. Both Mg₃P₂ and H₂O₂ were found to be necessary for this lipid peroxidation, which under optimal conditions produced a seven‐fold increase in malondialdehyde relative to basal levels in cod liver oil with H₂O₂ but no PH₃. Under the same conditions, 15‐, 9‐ and 2‐fold increases in malondialdehyde were obtained from ethyl arachidonate, methyl linoleate and methyl oleate. Small amounts of hydroxyl radical from PH₃/H₂O₂ were trapped with salicylic acid. Reactive oxygen species for lipid peroxidation may therefore be derived from direct reaction of PH₃ with H₂O₂ as an alternative hypothesis to their respiration‐linked formation. © 2000 Society of Chemical Industry     

Antioxidation responses of maize roots and leaves to partial root-zone irrigation

Antioxidation responses of maize roots and leaves to water deficit and rewatering under partial root-zone irrigation (PRI) were investigated using a pot system. Plants were cultured using three irrigation methods, i.e. conventional irrigation (CI), alternate PRI (APRI) and fixed PRI (FPRI) with three different water regimes including W₁ (70% field capacity, FC), W₂ (50% FC) and W₃ (35% FC). Compared to CI, root peroxidases (POD) activity was enhanced in the irrigated root zone of FPRI and both root zones of APRI during mild water deficit. After rewatering, POD activity was increased in the dry root zone under FPRI but reduced in the roots under APRI. Roots in the dry zone and leaves under FPRI remained high superoxide dismutase (SOD) activity after rewatering. In contrast, SOD activity decreased in the roots and leaves under CI and APRI. Malondialdehyde (MDA) contents were increased in leaves and two sub-roots under FPRI during water deficit and remained higher after rewatering compared to those under CI and APRI. MDA contents in the tissues under APRI showed similar levels to those under CI. Compared to CI, APRI showed the same biomass production, achieving significantly higher water use efficiency under mild water deficit. The results suggested that plants under APRI experienced less oxidative stress or damage induced by water deficit.     

不同肥种对蓝莓菌根侵染特性及土壤理化性质的影响

为探究不同肥种对蓝莓菌根及土壤理化性质的影响,以7年生兔眼蓝莓‘灿烂’为试材,研究了6种处理(CK、DP、HH、KS、LZ和HF)对蓝莓菌根着生状态及侵染率、根系活力、根系丙二醛(MDA)含量、土壤主要营养成分含量及蓝莓产量的影响。结果表明:蓝莓菌根菌着生普遍,DP处理的蓝莓菌根侵染率最高,且与HH、KS处理的菌根侵染率均达到3级;5种施肥处理均显著提升蓝莓的根系活力(P<0.05),DP处理的蓝莓根系活力最高;5种施肥处理显著降低了蓝莓根系MDA含量;LZ处理的结果数、坐果率、单果质量、单株产量均达到较高水平。综上所述,LZ、HF和DP处理均能显著降低土壤pH,整体提高土壤综合肥力,增加蓝莓产量。因此在蓝莓生产上,建议适当增加土壤有机质、有机酸和全钾的含量,有利于提高蓝莓菌根侵染率和根系活力,降低蓝莓根系MDA含量。     

不同氮肥处理对小麦生育后期旗叶生理活性的影响

对不同生育时期追施氮肥与超高产小麦生育后期旗叶生理活性的变化进行了研究。结果表明：在后期生长过程中,小麦旗叶超氧化物歧化酶（ＳＯＤ）活性、叶绿素含量总体呈现下降趋势,膜脂过氧化产物丙二醛（ＭＤＡ）含量、外渗电导率总体呈现上升趋势。中后期适量追肥可抑制叶绿素的降解,使植株体内保持高水平的保护酶活性,降低后期细胞膜脂过氧化水平,延长叶片的功能期。