葡聚六糖诱导后黄瓜叶片几种酶的活性变化动态     

范海延  李宝聚  曲波 《农业工程学报》2005,21(14):238-239

该文以葡聚六糖为试材，研究了葡聚六糖叶面喷施诱导后黄瓜幼苗叶片5种酶的活性变化状态，研究结果表明：葡聚六糖诱导的黄瓜幼苗叶片中几丁质酶、β-1,3-葡聚糖酶、苯丙氨酸解氨酶和多酚氧化酶活性明显增加，而抗坏血酸氧化物酶活性呈下降趋势，这些酶活性的变化可能与葡聚六糖诱导黄瓜幼苗的抗病机制相关。  相似文献   

烟草诱导抗病性及其应用   总被引：1，自引：0，他引：1  

李巧玲  魏运民  李晶  谢成建  杨星勇 《河南农业科学》2015,(6)

烟草诱导抗病性是通过诱导因子诱导烟草自身的抗病潜力,是烟草重要的抗病机制之一。概述了烟草诱导抗病性的诱导因子、机制及其应用,为烟草诱导抗病性的进一步研究提供理论基础。  相似文献   

玉米单倍体诱导及化学加倍方法的研究   总被引：2，自引：0，他引：2  

慈佳宾  杨巍  任雪娇  崔学宇  张野  张艳辉  杨伟光 《华南农业大学学报》2015,36(3):49-53

【目的】玉米单倍体的诱导及加倍.【方法】以北方春玉米区高抗丝黑穗病自交系K88和高感丝黑穗病自交系G115的杂交F1代作为母本,以5个诱导系(JS6-11~JS6-15)作为父本,进行单倍体杂交诱导试验;以秋水仙素作为玉米单倍体人工染色体加倍药剂,采取4种(浸根法、浸芽法、滴心叶法、针刺生长点法)处理方法,每种方法设置3个浓度梯度(0.2、0.4和0.6 mg·m L-1),并分别以体积分数2%DMSO+5%甘油溶液作为辅助药剂,进行单倍体加倍试验.【结果和结论】花丝长短和授粉时间对单倍体诱导率有重要影响.延迟授粉(长花丝≥7cm)的平均单倍体诱导率为17.0%,约为正常授粉(短花丝≤4 cm)条件下的3.3倍;伏后授粉的诱导率平均为18.4%,约为伏期授粉的3.4倍,证明延迟授粉时间和较低的温度有利于提高单倍体诱导率.秋水仙素加倍试验表明,浸根法对植株伤害较严重,存活率低于50%;针刺生长点法(0.6 mg·m L-1)和滴心叶法(0.4 mg·m L-1)的散粉率较高(45.9%,28.9%),相应的结实率也较高(15.2%,11.1%),说明针刺生长点法处理效果最好,滴心叶法次之.  相似文献   

VA系统诱导烟草对TMV抗性与细胞内防御酶系统的关系   总被引：7，自引：0，他引：7  

李兴红  贾月梅  商振清  崔丽华 《河北农业大学学报》2003,26(4):21-24

枯斑三生烟(Nicotiana tabacum L.“Samsum”NN)经植物源抗病毒剂VA诱导处理后第7天(清水处理作对照)，在其长出的新叶上接种烟草花叶病毒(TMV)。结果表明，VA可以诱导枯斑三生烟对TMV产生系统抗性，其枯斑抑制率可达57．25％，枯斑出现时间推迟10h。超氧物歧化酶(SOD)、过氧化物酶(POX)和苯丙氨酸解氨酶(PAL)3种酶的活性均比对照明显提高，其中48h时增加幅度最大；VA处理使枯斑三生烟叶片内的丙二醛(MDA)含量降低，其中接种48h时降低幅度最大。此外，在接种TMV后的12h内，清水对照的枯斑三生烟新叶中POX和SOD活性呈下降趋势，PAL活性几乎无变化，随后呈上升趋势，而经VA处理的枯斑三生烟新叶中的POX、SOD和PAL，活性自接种后，一直呈上升趋势，且上升幅度也高于对照；MDA含量的变化与3种酶活性的变化呈相反趋势。  相似文献   

辐射作用下含修复DNA主链断裂随机动力学理论的研究——单链与双链断裂规律     

赵玉芳  凌备备 《浙江大学学报(农业与生命科学版)》1993,(1)

按照我们在文献[1]中给出的辐射诱发含修复DNA主链断裂随机动力学理论数学模型,在此基础上,本文进一步导出了两种不同形成过程的双链断裂变化规律。在一定近似下,可以对SSB及DSB的实验结果作出满意的解释。我们的理论可以避免靶学说与击中理论的主要缺点,在一定条件下则又可以还原为靶理论结果,而且本理论还具有容纳更多因素的优点。  相似文献   

我国农机作业委托中介组织发育问题的研究     

郭鸿鹏  张明飞  杨印生 《农机化研究》2006,(3):14-16

依据新制度经济学的制度变迁理论,分析了我国农机作业委托中介组织发育路径的选择问题;指出了我国农机作业委托中介组织的发育应以诱致性变迁为主;并提出了促进农机作业委托发展的政策建议.  相似文献   

人工流产刮宫物中绒毛膜促性腺激素的提取和纯化     

李力权  袁鸿锦  赵永昌  张鸿志 《中国兽医学报》1991,(4)

以健康妇女人工流产的刮宫物为原料,经50%乙醇溶液抽提、醋酸钠50%乙醇缓冲溶液分级沉淀、硫酸铵分段盐析,最后用DEAE—纤维素柱层析纯化.终产品放免活性为3500IU/mg,产品总回收率为40～50mg‰.终产品经PAG圆盘电泳分析,只出现1条电泳区带,并与纯度相近的尿HCG产品的电泳特性一致.  相似文献   

解淀粉芽孢杆菌LJ02对黄瓜抗灰霉病菌的生防效果及其诱导抗性机理的初步研究     

柴庆凯  张斌  常若葵  刘慧芹  田小卫  王远宏 《植物病理学报》1955,49(6):828-835

 为了解生防解淀粉芽孢杆菌LJ02诱导黄瓜抗灰霉病菌的防治效果和作用机制,分别测量了LJ02的发酵上清液和菌体悬浮液的诱导持效期、最适使用浓度以及最佳施用方法,并采用荧光定量PCR的方法法测定了LJ02诱导处理后黄瓜根部和叶部组织中分别表达PR1a蛋白、β-1,3-葡聚糖酶、几丁质酶、过氧化物酶的抗性基因PR-1、PR-2、PR-3、PR-9的相对表达量。结果表明,LJ02诱导黄瓜抗灰霉病菌的持效期在7 d左右,且原液与100倍稀释液效果最好,灌根施用效果最佳。LJ02发酵上清液可诱导PR-1、PR-3、PR-9的表达,LJ02菌体悬浮液可诱导PR-1、PR-2、PR-3的表达。  相似文献   

Unsaturated fatty acids from zoospores of <Emphasis Type="Italic">Sclerospora graminicola</Emphasis> induce resistance in pearl millet     

K.?N.?Amruthesh  N.?P.?Geetha  H.?J.?Lyngs J?rgensen  E.?de?Neergaard  H.?Shekar Shettyappbot@sancharnet.in" title="hss_uom@hotmail.com  appbot@sancharnet.in" itemprop="email" data-track="click" data-track-action="Email author" data-track-label="">Email author 《European journal of plant pathology / European Foundation for Plant Pathology》2005,111(2):125-137

Downy mildew of pearl millet, caused by Sclerospora graminicola, is a devastating disease, resulting in high economic losses in the semi-arid regions of the world. Recently, induction of host plant resistance using biotic and abiotic inducers are included among disease management practices as an eco-friendly approach. Unsaturated fatty acids are considered as a new generation of plant disease resistance inducers. In the present study, six unsaturated fatty acids, viz. docosahexaenoic acid (DHA), eicosapentaenoic acid (EPA), arachidonic acid (AA), linolenic acid, linoleic acid and oleic acid, all originally detected in the zoospores of S. graminicola,were applied to seeds of susceptible cultivars of pearl millet to examine their ability to protect against downy mildew under greenhouse and field conditions. In greenhouse experiments, EPA and AA induced a maximum of 78.6% and 76.5% protection, whereas linoleic acid, DHA and linolenic acid provided up to 66.3%, 61.2% and 24.5% protection, respectively. Oleic acid was not effective in protecting pearl millet (only 5.1% protection). A time interval of four days between treatment of seeds and challenge inoculation was required to obtain optimum protection. Plants raised from treated seeds and challenge inoculated at the tillering and inflorescence stages showed enhanced resistance, resulting in higher grain yield compared to untreated plants of the same cultivar. Chitinase activity was found to be higher in susceptible seedlings of pearl millet after treatment with the fatty acids and pathogen inoculation than in seedlings only inoculated with the pathogen. This indicates that host defence responses are activated and thus that induced resistance is involved in the protection observed. The role of unsaturated fatty acids as activators of resistance against downy mildew in pearl millet is discussed.  相似文献   

Luteoforol,a flavan 4-ol,is induced in pome fruits by prohexadione-calciumand shows phytoalexin-like properties against <Emphasis Type="Italic">Erwinia amylovora</Emphasis>and other plant pathogens     

Francesco?SpinelliEmail author  John-Bryan?Speakman  Wilhelm?Rademacher  Heidi?Halbwirth  Karl?Stich  Guglielmo?Costa 《European journal of plant pathology / European Foundation for Plant Pathology》2005,112(2):133-142

Treatments with prohexadione-calcium led to lowered incidence of fire blight, scab and other diseases in pome fruit trees and other crop plants. In addition to acting as a growth regulator, prohexadione-calcium interferes with flavonoid metabolism and induces the accumulation of the 3-deoxycatechin luteoliflavan in shoots of pome fruit trees. Luteoliflavan does not possess any remarkable antimicrobial activity. Therefore luteoforol, its unstable and highly reactive precursor, has been tested in vitro for its bactericidal and fungicidal activities. Luteoforol was found to be highly active against different strains of Erwinia amylovora, the causal agent of fire blight, and all other bacterial and fungal organisms tested. Phytotoxic effects were also observed in pear plantlets. The results obtained indicate that prohexadione-calcium induces luteoforol as an active principle with non-specific biocidal properties. It is proposed that luteoforol is released upon pathogen attack from its cellular compartment and inhibits further disease development by destroying pathogen cells as well as by inducing a hypersensitive-like reaction in the host plant tissue. This mechanism would be closely analogous to the one known for structurally related phytoalexins in sorghum.  相似文献