生防菌粗毒素对猪殃殃防御酶及叶片细胞膜透性的影响

为了揭示生防菌的致病机理,用3株生防菌粗毒素处理猪殃殃叶片,测定其过氧化氢酶(CAT)、超氧化物歧化酶(SOD)、过氧化物酶(POD)的活性、电导率和丙二醛(MDA)含量,探讨生防菌粗毒素对叶片防御酶活性及叶片细胞膜透性的影响。结果表明,3株生防菌粗毒素使猪殃殃叶片组织细胞膜透性上升,MDA含量上升;毒素处理后的猪殃殃叶片中POD、SOD和CAT的活性均较不处理的对照升高。     

黑胫病生防菌施用后对不同抗性烟草品种酶活性和 MDA 含量的影响

为了探究生防菌对烟草抗病性的影响,2012年,以对黑胫病抗性不同的高抗品种（云烟87）、中抗品种（ K326）和感病品种（红花大金元）等3种烟草品种70天苗龄的实生苗为实验材料,在烟苗茎秆接种黑胫病原后施用该生防菌,于不同接种时期（0天、15天、30天、45天、60天、75天）测定叶片中苯丙氨酸解氨酶（PAL）、多酚氧化酶（PPO）、过氧化物酶（POD）的活性及丙二醛（MDA）含量。结果表明,（1）高抗品种、中抗品种和感病品种的PAL、 PPO及POD活性水平皆明显高于各自的对照,且前期增加速度表现为高抗品种＞中抗品种＞感病品种,后期PPO活性减小情况也符合以上规律。（2）高抗品种、中抗品种和感病品种的MDA的含量增加速度明显低于各自的对照,前期MDA含量增加的速度和后期降低的速度均是感病品种＞中抗品种＞高抗品种。可见,施用该生防菌可通过调节抗性酶活性和MDA含量提高烟株对烟草黑胫病的抗病性。     

喹乙醇对鲤肝胰脏抗氧化酶系统的影响

用含不同剂量喹乙醇(0～3200mg·kg-1)的饲料饲喂鲤,分别对鲤在摄食3、6、9和12周时肝胰脏中超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH px)等抗氧化酶活性、脂质过氧化物丙二醛(MDA)含量及总抗氧化能力(T AOC)进行了测定。结果表明,SOD活性随饲料喹乙醇剂量的升高总体上呈升高的趋势,试验时间对各个处理组的SOD酶活性影响不大。饲料中喹乙醇对GSH px活性的影响较小,其剂量达1600mg·kg-1以上时GSH-px酶活性变化明显,主要表现为诱导效应。饲料中喹乙醇剂量的改变大体上不对MDA含量产生影响,且随时间的延长,除3200mg·kg-1组外,其余各实验组的MDA含量都有所降低。随喹乙醇剂量的增加和实验时间的延长,T AOC均呈现降低的趋势,其中以1600和3200mg·kg-1组的下降幅度最大。结果提示,高剂量下喹乙醇对抗氧化酶活性影响较大,并伴随着机体抗氧化能力的减弱。     

Olive leaves (Olea europea L.) and α‐tocopheryl acetate as feed antioxidants for improving the oxidative stability of α‐linolenic acid‐enriched eggs

Ninety‐six brown Lohmann laying hens were equally assigned into four groups with six replicates. Hens within the control group were fed a corn–soybean‐based diet supplemented with 4% linseed oil. Two other groups were given the same diet further supplemented with 5 or 10 g ground olive leaves/kg feed, while the diet of the fourth group was further supplemented with 200 mg α‐tocopheryl acetate/kg. Supplementing diets with olive leaves had no effect on egg production, feed intake and egg traits. Eggs collected 28 days after feeding the experimental diets were analysed for lipid hydroperoxides and malondialdehyde (MDA) content, fatty acid profile, α‐tocopherol concentrations and susceptibility to iron‐induced lipid oxidation. Olive leaves were also analysed for total and individual phenolics, and total flavonoids, whereas their antioxidant capacity was determined using both the DPPH (1,1‐diphenyl‐2‐picrylhydrazyl) and ABTS (2,2‐azinobis3‐ethylbenzothiazoline‐6‐sulphonic acid) radical scavenging activity assays. Results showed that neither α‐tocopheryl acetate nor olive leaves supplementation exerted (p > 0.05) any effect on the fatty acid composition of n‐3 eggs. Supplementing the diet with 5 g olive leaves/kg had no (p > 0.05) effect on the hydroperoxide levels of n‐3 eggs, while supplementing with 10 g olive leaves/kg or 200 mg α‐tocopheryl acetate/kg, the lipid hydroperoxide levels were reduced (p ≤ 0.05) compared to control. However, although hydroperoxides were reduced, MDA, a secondary lipid oxidation product, was not affected (p > 0.05). Iron‐induced lipid oxidation increased MDA values in eggs from all groups, the increase being higher (p ≤ 0.05) in the control group and the group supplemented with 5 g olive leaves/kg. The group supplemented with 10 g olive leaves/kg presented MDA values lower (p ≤ 0.05) than the control but higher (p ≤ 0.05) than the α‐tocopheryl acetate group, which presented MDA concentrations lower (p ≤ 0.05) than all other experimental diets at all incubation time points.     

镉处理下青菜和白菜MDA含量、POD和SOD活性的变化

采用溶液培养的方法,比较研究了芸苔属植物青菜和白菜在过量镉(Cd)处理下膜脂过氧化和保护酶活性的变化。结果表明,白菜对Cd毒害的耐性大于青菜。Cd处理增加了两种植物叶片膜脂过氧化产物MDA(丙二醛)的含量,提高了叶片POD(过氧化物酶)的活性,其中当Cd处理浓度为100μmol·L-1时,青菜叶片内MDA含量上升比白菜叶片内MDA含量上升更明显。白菜叶片内SOD(超氧化物歧化酶)活性随着Cd处理浓度的增加而升高,而青菜叶片内SOD活性在低浓度Cd胁迫下,随Cd处理浓度的增加而升高;但当Cd浓度为100μmol·L-1时,SOD活性却下降为白菜的81%。     

产后健康奶牛血液流变学和氧自由基变化

观察产后健康奶牛1－30d血液流变学和氧自由基主要指标动态变化。选择2－4胎龄产后健康奶牛18例，于产后1d,2d,4d,7d,10d,15d,30d采血，检测血液流变学主要指标（全血高切比粘度ηb80S^-1、全血低切比粘度ηb20S^-1、血浆比粘度ηp、血细胞压积PCV和血浆纤维蛋白原FG）和氧自由基主要指标（超氧化物歧化酶SOD和丙二醛MDA）的变化。结果发现，血液流变学和氧自由基大多数指标30d,16d与新产1－7d比较，至少在某一时间段呈现差异极显著或显著（P＜0．01或P＜0．05）。     

离体条件下盐胁迫对马铃薯试管苗叶绿素含量,脯氨酸累积和抗氧化酶活性的影响

离体条件下,研究了2个马铃薯品种在0～80 mmol NaCl胁迫下的试管苗生长、叶绿素含量、脯氨酸和丙二醛含量及氧化酶活性的反应.2品种苗高随盐浓度增加及培养时间的延长而显著降低.与品种紫花白相比,同一盐浓度下静石2号在苗鲜重、根长和根数等方面受抑制程度更强.盐胁迫培养3周后,试管苗叶片中叶绿素a,b与总量及类胡萝卜素含量在40～80 mmol高盐浓度下显著降低.两个品种试管苗中脯氨酸和丙二醛含量随盐浓度的增加而增加,而静石2号中脯氨酸和丙二醛的累积量和累积率都高于紫花白,表明在盐胁迫下静石2号膜脂过氧化程度相对较高.2品种SOD和POD活性均在低盐浓度(20 mmol)下显著增加而高盐浓度下降低.离体条件下,紫花白试管苗呈现出比静石2号高的SOD、POD活性以及较强的耐盐能力,表明其具有进一步在田间进行耐盐基因型筛选的必要性.     

水稻结实期间叶片衰老与膜脂过氧化的关系

 以结实期间的稻为材料，在抽穗开花期通过剪去穗部部分枝梗和全穗等处理后，测定作为叶片衰老指标的叶绿素和蛋白质含量及作为膜脂过氧化指标的丙二醛含量的变化，探讨了水稻结实期间叶片衰老与膜脂过氧化之间的关系。试验结果指出，在水稻抽穗开花期间，剪去穗部枝梗或整个穗子，叶片中的叶绿素和蛋白质含量下降速率在处理后的7 d内就开始明显减慢，而MDA含量增加速率只有在处理7 d后才开始减缓，SOD活性并不因剪穗处理而有所提高。表明因剪穗(或穗部枝梗)而导致的叶绿素和蛋白质含量的变化早于MDA含量的变化，与SOD活性的变化无直接关系。说明在结实期间，水稻叶片在衰老过程中表现出的叶绿素和蛋白质含量的下降，并不主要是由于SOD的活性降低而导致膜脂过氧化作用增强所造成的结果，SOD活性下降和MDA含量的增加可能与叶绿素及蛋白质含量减少一样，只是叶片衰老开始后的一种结果，而非引起叶片衰老的原因。     

两种菊芋耐盐差异研究

To explore genetic variability for two Jerusalem artichoke (Helianthus tuberosus) cultivars, N1 (the sixth-generation cultivated with 75% seawater irrigation for six years) and N7 (a general variety), a experiment was conducted to study the changes in physiological attributes under different concentrations (0%, 10% and 25% of seawater concentration in greenhouse and 0%, 30% and 50% of seawater concentration in the field) of seawater salinity stress. In the greenhouse experiment, decreases of dry growth rate, but increases of dry matter percentage and membrane injury occurred in both the genotypes at 10% and 25% seawater treatments, although lesser cell membrane damage was observed in N1 than N7. N1 accumulated greater contents of Na⁺, Cl^-, soluble sugar and proline in leaves compared with N7. In the field experiment, the yields of shoot, root and tuber, and the contents of total-sugar and inulin in tubers of N1 were higher than those of N7. Lesser degree of salt injury in N1 indicated that the relatively salt-tolerant cultivar had higher K⁺/Na⁺ ratio, lower Na⁺/Ca²⁺ ratio, and the salt-induced enhancement of osmotic adjustment.     

盐胁迫对萱草生长及其相关生理特性的影响

为了探明盐胁迫对萱草生长及其相关生理特性的影响,采用水培试验,对重瓣大花萱草(Hemerocallis fulva var.florepleno)、玫瑰红萱草(Hemerocallis.fulva var.rosea)、黄花菜(Hemerocallis citrina)和大花萱草(Hemerocallishybriaa)在NaCl质量分数分别为0.0%,0.2%,0.4%,0.6%,0.8%,1.0%的水溶液下的生长及相关生理变化进行了研究.结果表明:1)4个萱草材料在0.2%～0.6%的NaCl胁迫下,叶片伤害指数较小,根的生长只受到了轻微的抑制,胁迫后第20天,平均新根数≥3.67条;在0.8%～1.0%NaCl的胁迫下,叶片伤害指数较大,根系生长受到严重的抑制,并且还表现出了一定的基因型差异.以伤害指数和新根数量衡量萱草的耐受能力从大到小依次为重瓣大花萱草、大花萱草、黄花菜、玫瑰红萱草.2)在1.0%的盐(NaCl)胁迫下,随着胁迫时间的延长,萱草叶片中丙二醛(MDA)含量和质膜外渗率基本呈逐渐增加的趋势,这与形态观察指标测定的伤害程度相吻合,即盐胁迫下的MDA含量、质膜外渗率的变化可作为萱草耐盐性的鉴定指标.