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植物源农药的活性成分和作用机理 总被引:9,自引:0,他引:9
植物源农药一般具有在环境中生物降解快、不易产生抗性、一般对人畜安全等优点,成为潜在的化学合成农药替代物。本文对植物源农药的活性成分和作用机理做简要综述。 相似文献
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本文以腐食酪螨基因组DNA为模板,采用逐个参数优化法,探讨腐食酪螨ISSR实验的最佳反应体系。实验结果表明,腐食酪螨ISSR-PCR最佳反应体系:总体积25μL,其中Mg2+1.5 mM;10×Buffer 2.5 mM;dNTPs 0.2 mM;ISSR引物0.2μM;模板DNA 50 ng;Taq DNA聚合酶0.75 U。扩增程序为:94℃预变性5min,94℃变性1 min,(48℃、50℃、52℃)复性1 min,72℃延伸1.5 min,循环35次,结束后72℃延伸5 min,4℃保存。同时通过梯度退火实验,确定不同引物的最佳退火温度。 相似文献
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L'udmila Slováková Desana Lišková Peter Capek Marta Kubačková Daniela Kákoniová Štefan Karácsonyi 《European journal of plant pathology / European Foundation for Plant Pathology》2000,106(6):543-553
Galactoglucomannan-derived oligosaccharides (GGMOs) showing biological activity in growth, morphogenesis and cell viability were tested in a host pathogen interaction. As a model system, cucumber (Cucumis sativus L. cv. Laura) reacting hypersensitively to tobacco necrosis virus (TNV) was used. The defence reactions were dependent on the degree of polymerisation and concentration of oligosaccharides, as well as on the time of application of virus to plant cotyledons. Disease symptoms were inhibited by 60–75%. The average number of lesions per cotyledon was significantly decreased when oligosaccharides were used simultaneously or 24h prior to virus inoculation. Significant changes in peroxidase, beta-glucanase and chitinase activities accompanied the defence reaction. It can be concluded that oligosaccharides derived from spruce galactoglucomannan induce non-specific resistance to local viral infection in plants. GGMOs probably act as inhibitors of the virus infection, rather than inhibitors of direct virus multiplication. 相似文献
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Morphological and histochemical investigation of the response of Olea europaea leaves to fungal attack by Spilocaea oleagina
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This study investigated the response of Olea europaea (cv. Conservolea) leaves to attack by the fungal pathogen Spilocaea oleagina. Cryostat and semithin sections of healthy and S. oleagina‐infected olive leaves were analysed histochemically for polyphenol oxidase (PPO) activity and tested for programmed cell death (PCD) induction by means of terminal deoxynucleotidyl transferase‐mediated dUTP nick end labelling (TUNEL). At all stages of infection, the fungus remained localized between the external and internal layers of cuticle without crossing the pectocellulosic layer. No PCD phenomena could be detected in plant cells at any stage of the disease. However, extensive degeneration of palisade parenchyma cells was observed in advanced infections, with massive loss of cytoplasmic contents and disappearance of cell compartments. Polyphenol oxidases are enzymes that, in olive, oxidize o‐diphenols (principally oleuropein and rutin) to produce o‐diquinones and melanins, substances that are toxic to many pathogens. No significant increase in overall PPO activity was found in infected leaves; on the contrary, enzyme activity was gradually lost as infection progressed, most probably due to degradation of plastids within mesophyll cells, in which such enzymes are normally confined. Only a limited local PPO activation occurred in a few upper epidermal cells of the leaf, indicating a feeble induction of a plant response. 相似文献
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鄂尔多斯盆地南区环河组地下水水岩作用研究 总被引:2,自引:0,他引:2
文中以揭示鄂尔多斯盆地南区白垩系环河组地下水水化学场的形成机理为主要研究目的。在了解鄂尔多斯盆地水文地质条件的基础上,分析了环河组地下水水化学演化特征,应用Phreeqc软件对其进行了水-岩作用的地球化学模拟,定量分析研究了该区地下水的演化过程、形成机理,并进一步分析了南区环河组地下水的补、径、排关系。得出结论为:在水流模拟路径上主要发生了石膏、岩盐、斜长石、钾云母或钾长石的溶解反应和阳离子交替吸附作用,导致地下水的TDS不断增大;其间,受总排泄带位置及东西两侧径流的影响,使水化学演化方向、径流方向产生朝向总排泄带的"向心"偏转,因此,环河组大体上以马莲河入泾河汇入口附近为中心,形成半个向心椭圆状的地下水流动系统。该结论对盆地南区地下水流动系统的划分、边界界定,具有特殊意义。 相似文献
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在室内控制条件下对甲磺隆降解菌S113(Methylopila sp.)的水解酶进行了研究,发现该酶为胞内酶、非诱导酶。建立了甲磺隆水解酶的酶促反应体系:2 830 μL Na2HPO4-NaH2PO4缓冲液(0.2 mol/L,pH 7.0),150 μL甲磺隆(1 000 mg/L),20 μL粗酶液(约1.2 μg粗蛋白),30℃水浴30 min。甲磺隆水解酶pH值稳定范围为6~9,最适pH值为8.0。水解酶热不稳定,45℃处理30 min,酶活下降59.22%,70℃处理30 min可完全灭活。测定了8种金属离子对水解酶的作用,发现 1 mmol/L 的Ca2+对酶活有促进作用。 相似文献
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本文将黑化反应和血细胞总数(THC)计数两种检测方法用于桔小实蝇幼虫辐照处理后活性检测研究中。黑化研究结果表明:桔小实蝇幼虫经辐照,在-18℃,15 min处死后,室温条件下30 min内黑化程度不明显,但是用作对照的1龄幼虫从1.5 h开始、2龄幼虫从2 h开始、3龄幼虫从2.5 h开始虫体显著变黑,而经辐照的虫体变黑的时间比对照样至少延迟.0.5 h,且辐照剂量越大,黑化反应出现的时间越晚。表明辐照会抑制幼虫黑化,黑化反应可用于快速检测实蝇幼虫是否经过辐照。血细胞总数计数研究结果表明辐照处理的桔小实蝇幼虫血细胞总数显著减少,且同一辐照剂量下,龄期越高,血细胞总数越多。利用上述两种方法可定性判定桔小实蝇幼虫是否经过辐照处理。 相似文献
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Miaw-Fan Chen Chan-Pin Lin 《European journal of plant pathology / European Foundation for Plant Pathology》1997,103(2):137-145
EcoRI restriction fragments of genomic DNA from the phytoplasma associated with peanut witches'-broom (PNWB) were cloned in plasmid pGEM-3Zf(+). Cloned inserts from seven PNWB-phytoplasma-specific recombinant plasmids and two subcloned plasmids were excised with restriction enzymes, labeled with digoxigenin, and used as probes. Probe PNWB281 and its derivative subclones PNWB281-4 and PNWB281-5 hybridized with DNA from PNWB-phytoplasma infected peanut and periwinkle specifically but not with DNA from healthy plants or plants infected with phytoplasmas associated with sweetpotato witches'-broom (SPWB), loofah, Ipomoea obscura, and paulownia witches'-broom, elm and aster yellows, rice yellow dwarf, and bamboo little leaf disease. Six other probes hybridized with DNA derived from PNWB and SPWB-phytoplasma-affected periwinkle but not with DNA from healthy plants or plants infected with other phytoplasmas mentioned. In Southern hybridizations, four of the nine cloned and subcloned probes could differentiate the PNWB-phytoplasma from SPWB-phytoplasma. Three primer pairs for PCR were synthesized according to the partial sequences at both ends of the cloned inserts and were able to distinguish PNWB-phytoplasma from SPWB-phytoplasma by using PCR for the first time. A minimum of 1 pg and 10 pg of total DNA from diseased periwinkle and peanut, respectively, was sufficient to amplify the specific PNWB-phytoplasma PCR fragments, allowing the detection of PNWB-phytoplasma DNA from healthy-looking periwinkle plants two weeks after graft inoculation. 相似文献
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以小菜蛾(Plutella xylostella)基因组DNA为模板,采用L16(45)正交试验设计方法,建立小菜蛾的ISSR最佳反应体系。通过梯度退火试验,确定不同引物的最适退火温度。优化得到的反应体系(20μL)为:Mg2+浓度1.5mmol/L、Taq DNA聚合酶2.5U、dNTPs浓度0.2mmol/L、引物浓度1.25μmol/L、模板DNA量20ng。反应程序为:94℃预变性5.0min;94℃变性45.0s,40~61℃(不同引物退火温度各异)退火1.0min,72℃延伸1.5min,40个循环;72℃延伸10.0min;10℃保存。利用所建立的ISSR-PCR反应体系,获得了清晰、重复性好的DNA谱带。 相似文献
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Mehmet A Oturan Jean-Jacques Aaron Nihal Oturan Jean Pinson 《Pest management science》1999,55(5):558-562
The degradation of five chlorophenoxyacid herbicides has been studied using an electrochemical method based on the Fenton reaction (simultaneous reduction of dioxygen and ferric ions). The method consists of electrosynthesizing OH· radicals, which react rapidly with chlorophenoxyacids in aqueous media. HPLC and GC-MS analysis show the formation of polyhydroxyphenols and quinones in a first step, and the complete destruction of the aromatic nucleus upon exhaustive electrolysis. This offers a possible way for the depollution of natural waters containing chlorophenoxyacid pesticide residues. © 1999 Society of Chemical Industry. 相似文献
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鄂尔多斯盆地洛河组地下水地球化学模拟——以陕西省长武-彬县地区为例 总被引:3,自引:0,他引:3
文中以揭示鄂尔多斯盆地长武-彬县地区白垩系洛河组地下水水化学场的形成机理为主要研究目的。在了解鄂尔多斯盆地的地形、地势、地貌、新构造运动、岩石类型、岩性构造和其他特征的基础上,运用化学热力学原理、质量作用定律和质量守恒定律,应用水文地球综合分析方法和地下水地球化学模拟技术,对白垩系洛河组地下水进行了水-岩作用的地球化学模拟。应用Phreeqc软件定量分析研究了该区地下水的演化过程、形成机理,总结了矿物或次生矿物的溶解沉淀规律以及水溶液中化学成分的变化,主要结论为:1)在水流模拟路径上主要发生了方解石与伊利石的沉淀和白云石、石膏、岩盐、斜长石、钾长石和钾云母的溶解,以及Ca-Na2间的阳离子交换作用;2)在水D20点南附近可能是洛河含水岩组地下水的排泄基点。结果表明水-岩作用模拟结果有助于揭示研究区地下水化学环境的演化机制。 相似文献
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马铃薯卷叶病毒Potato leafroll virus(PLRV)是目前严重影响马铃薯产量与品质的主要病毒之一,给马铃薯产业造成巨大损失。本研究采用环介导等温核酸扩增(loop-mediated isothermal amplification, LAMP)技术建立PLRV的RT-LAMP检测方法。采取单因素变化试验,对RT-LAMP反应体系中多个因素包括引物组合、温度条件及Mg~(2+)、betaine、Bst 3.0 DNA聚合酶、dNTPs、UNG、SYBR GreenⅠ和引物组合的浓度进行一系列试验和优化。采用RT-PCR检测方法进行平行比对试验,对优化后的RT-LAMP反应体系进行了验证。结果表明,最佳引物组合为P3,最适反应温度62℃,25μL反应体系中,Mg~(2+)、betaine、Bst 3.0 DNA聚合酶和UNG的最佳终浓度分别为4 mmol/L、0 mmol/L、0.64 U/μL和0.08 U/μL,dNTPs的最佳用量为1μL(dATP、dGTP、dCTP各0.4 mmol/L,dUTP 1.2 mmol/L),SYBR GreenⅠ(20×)的最佳用量1μL,primer mix的最佳用量2.5μL(PLRV-FIP/BIP、PLRV-F3/B3和PLRV-LF/LB的浓度分别为0.8、0.2μmol/L和0.6μmol/L),RNA模板1μL(2 ng/μL),加DEPC-H_2O至25μL,反应时间50 min。优化后的RT-LAMP检测结果与RT-PCR一致,且可视化判读结果。因此,建立的PLRV RT-LAMP检测方法为进一步开发RT-LAMP检测试剂盒及其实际应用奠定了基础。 相似文献
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我国大豆胞囊线虫生理分化动态的鉴定和监测研究 总被引:10,自引:0,他引:10
1994~1995年,对采自我国5省市(区)17个县(市)和其中4个多年重茬种植抗病品种开始感病地区的26个大豆胞囊线虫居群,在国际统一的鉴别品种上进行了生理小种鉴定。共鉴定出1~6个小种。其中6号小种当时为国内新记录;并扩大了1号、2号、3号、5号小种在国内的已知分布范围,生理小种1号在黑龙江、2号在内蒙古、3号在江苏、5号在山东,均为各该省(区)的新记录。而全国则仍以1,3,4号小种分布广,为主要致害小种。还明确监测出近年来在4个重要病区出现的大豆抗病品种持续连作重茬后失抗感病是各自的大豆胞囊线虫生理小种发生变异所致;而连作感病品种却仍为各自的原小种,只是病情加重;由之看出其病地重茬的危害具有两重性。 相似文献
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Microtubule dynamics in compatible and incompatible interactions of soybean hypocotyl cells with Phytophthora sojae 总被引:1,自引:0,他引:1
The arrangement of microtubules in soybean ( Glycine max ) cells was examined during compatible and incompatible interactions of hypocotyls of soybean cv. Harosoy (susceptible) and cv. Haro 1272 (resistant) with race 1 of the soybean-specific pathogen Phytophthora sojae . Both reaction types were similar during the first 3 h after zoospore inoculation in terms of the number of cells penetrated, and depth penetrated into the cortex. By 3 h postinoculation, clear differences had developed between the two interaction types: incompatible interactions were characterized by a hypersensitive response that was confined to single penetrated cells; while compatibly responding cells appeared unchanged. Both types of response were characterized by autofluorescence of cell walls or cytoplasm and, at 6 h after inoculation, complete disorganization of cell cytoplasm. Reorientation and loss of microtubules was seen in the early stages of the incompatible interaction in association with cellular hypersensitivity, but not in compatible responses. In cells adjacent to those that reacted hypersensitively, there was little evidence of change in microtubule orientation. Treatment of hypocotyls with the microtubule depolymerizer oryzalin prior to inoculation did not alter the compatible response, but led to breakdown of the incompatible response. Changes in microtubule orientation and state are thus among the first structural changes that are visible within cells during incompatibility in this system. 相似文献
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新疆棉铃虫赤眼蜂种系筛选—对温湿度的反应 总被引:6,自引:0,他引:6
对采自新疆棉铃虫的2个暗黑赤眼蜂地理品纱和1个广赤眼蜂品系以及从乌孜别克斯坦引进的2个暗黑赤眼蜂地理品系进行了对温湿度反应的比较研究。各赤眼蜂种(系)后代性比之间的差异受温湿度组合的影响较小。同一种系中,雌蜂倾向于在较高温度下产更多的卵,达到更高的寄生率,但性比(雄/雌)随温度升高而增大。在高温(35℃)低温(45%)条件下,暗黑赤眼蜂吐鲁番品纱的后代中雌性所占比较最高,其羽化率和发育历期与最高的种(系)无显著差异,尽管其寄生率仅次于最高的暗黑赤眼蜂喀什种群。说明赤眼蜂吐鲁番种群最能适应新疆高温干旱的气候环境,是一比较好的侯选品系。 相似文献
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Ruey-Shyang Chen Chishih Chu Chi-Wei Cheng Wen-Yu Chen Jwu-Guh Tsay 《European journal of plant pathology / European Foundation for Plant Pathology》2008,121(1):1-8
Powdery mildew can be found in most sunflower fields during the winter season in Taiwan and causes severe yellowing on the
blade, petiole, stem, and calyx, as well as serious defoliation. Two types of powdery mildew fungi isolated from sunflower
leaves showed variable status for fibrosin bodies. But only the cleistothecium of Podosphaera xanthii, one of the pathogens causing this disease, was observed on samples from Chungpu County at the beginning of 2005. With a
species-specific primer pair, PN23/PN34, no specific PCR product was amplified from the pathogen’s genomic DNA. Based upon
the ITS sequence of rDNA, three PCR primer sets (S1/S2, G1/G2, and L1/L2) specific to P. xanthii, Golovinomyces cichoracearum and Leveillula taurica, respectively, were designed to detect and differentiate pathogens causing powdery mildews on sunflower. Only the primer
pairs S1/S2 and G1/G2 could amplify PCR products, with product sizes of 454 and 391 bp, respectively. Four samples of fungal
DNA were subjected to a multiplex PCR amplification with primer pairs S1/S2 and G1/G2; P. xanthii and G. cichoracearum were successfully detected. These results suggest that the multiplex PCR method is a rapid, simple, and effective technique
to detect and differentiate powdery mildews, for example P. xanthii and G. cichoracearum, found on sunflower. With morphologic characteristics, ITS sequence analysis and pathogenicity testing, P. xanthii and G. cichoracearum, the first case, are two powdery mildews on sunflower in Taiwan. 相似文献