共查询到20条相似文献，搜索用时 31 毫秒
1.
Cutinase purified from Fusarium solani f. sp. pisi was effectively inhibited by the fungicide benomyl. This irreversible inhibition was shown to be caused by the reaction of n-butylisocyanate, a breakdown product of benomyl, with the active serine in the enzyme. Methyl-2-benzimidazolecarbamate (MBC), the other breakdown product of benomyl, had no cutinase inhibitory activity. The fungicidal action of benomyl was measured by a bioassay using pea stems with or without intact cuticular and cell wall barriers. Benomyl prevented infection of Pisum sativum by conidia of F. solani f. sp. pisi only on intact pea stems with 50% efficiency at 7 μM, but was without effect on wounded stems or when benomyl (up to 50 μM) was applied 24 hr after inoculation with spores. Both MBC and benomyl strongly inhibited mycelial growth with 50% inhibition at 2 μM indicating a toxic mode of action. The prevention of fungal infection on only intact stem surfaces was established, however, with a fungal strain which was relatively tolerant to the toxic effect of these fungicides. With this strain complete protection was obtained at 5 μM benomyl which caused only 30% inhibition of growth. These results suggest that benomyl at low concentrations prevented fungal penetration and thus infection probably through inhibition of cutinase. It is also shown that treatment of cutin with n-butylisocyanate made it resistant to cutinase action. 相似文献
2.
J.-J. Bourgois R. Bronchart R. Deltour Th. de Barsy 《Pesticide biochemistry and physiology》1977,7(2):97-106
Ultrastructural changes produced by benomyl, a benzimidazole derivative, during the first 48 hr of germination of Fusarium oxysporum f. sp. melonis conidia are investigated; an attempt to localize 3H-benomyl by autoradiography was carried out. Benomyl has fungicidal and fungistatic activity. Indeed it causes the lysis of 10% of the germinating microconidia and reduces drastically the growth of the germ tube in the other cells. In this latter case, cell wall thickening and anomalous morphology have been observed. Lysosome-like vesicles appear in the cytoplasm. It is proposed that benomyl acts on membrane integrity. 相似文献
3.
Karen W. Smith Christopher T. Virgona Jocelyn N. Pennefather George Holan 《Pest management science》1996,46(3):247-253
Three previously reported methanesulfonate insecticides, 6-isobutylthio-2-pyridyl methanesulfonate ( I ) and its sulfoxide ( II ) and sulfone ( III )analogues were examined in two insect species Lucilia cuprina and Blattella germanica and in tissues from vertebrates. The results of B. germanica tests and cholinesterase assays confirmed the insecticidal activity of the compounds, with cholinesterase inhibition being the most likely mode of insecticidal action. The inactivity of the sulfide I and sulfoxide II in vertebrate in-vitro studies may indicate that conversion, in vivo, of the sulfide and sulfoxide methanesulfonates to the sulfone ( III ) is a requirement for activity. In mouse toxicity tests, matching high toxicity was observed for the alkylthio-, alkylsulfoxy- and alkylsulfone analogues indicating fast metabolic oxidation of the injected alkylthio- and alkylsulfoxy-compounds. However, in in-vitro tissue tests, the sulfone, although active, did not exhibit the characteristic pharmacological profile of the standard acetylcholinesterase inhibitor, physostigmine. The sulfone demonstrated a mixed action, with indications that it acts as an inhibitor of specific cholinesterase isozymes, or that it may modify responses at cholinoceptors. 相似文献
4.
A technique is described for testing isolates of Septoria tritici from winter wheat for resistance to benzimidazole fungicides. Secondary spores from 23 isolates were tested on Czapek Dox V-8 agar amended with benomyl at 1–10 μg ml. Twenty-one isolates were recovered from eight crops in England in 1984 and two (PBI isolates) were obtained in 1973. Thirteen isolates, including both PBI isolates, were sensitive to benomyl at 1 μg ml?1 and nine were resistant at 10 μg ml?1. The remaining isolate had a low proportion (1:3.7 x 104) of resistant spores. The minimum inhibitory concentration for sensitive isolates was 0.2–0.4 μg ml 1 benomyl and for resistant isolates was more than 1000 μg ml 1. Benomyl-resistant isolates were cross-resistant to carbendazim, thiabendazole and thiophanate-methyl, but not to 12 other fungicides with different modes of action. The implications of these findings are discussed. 相似文献
5.
Mary L. Arnold Albert D. Duriatti Michel Jung Ruth B. Katz John W. Liebeschuetz 《Pest management science》1995,44(4):341-355
A novel class of chemical has been designed with the aim of inhibiting the Δ14-reductase and Δ8-Δ7-isomerase enzymes in the ergosterol biosynthesis pathway in fungi. Use was made of knowledge about the mechanisms of both enzymes and the mode of action of known, fungicidal inhibitors of these enzymes. Pioneer examples have been synthesised and have been demonstrated to be potent inhibitors of ergosterol biosynthesis in Ustilago maydis (DC) Corda, acting in the same manner as the commercial fungicide fenpropimorph. They also showed excellent fungicidal activity against Erysiphe graminis DC f. sp. hordei Marchal (powdery mildew of barley) and Puccinia recondita Rob. ex Desm. (wheat leaf rust) in in-vivo glasshouse tests. Using these compounds as a starting point, systematic structural variation has been carried out. Testing of a wide range of analogues at high volume confirms the potential of this class of compound to control mildew and rust pathogens at levels comparable to those of the standards. Correlation of in-vivo and enzymatic data is good and the structure-activity relationship developed for this series of compounds closely parallels that found for the morpholine/piperidine class of fungicides, suggesting a common mode of action. 相似文献
6.
Survey of Fungicide Sensitivity in Colletotrichum gloeosporioides from Different Avocado and Mango Production Areas in South Africa 总被引：4，自引：0，他引：4
Gina M. Sanders L. Korsten F.C. Wehner 《European journal of plant pathology / European Foundation for Plant Pathology》2000,106(8):745-752
Pre-harvest fungicidal treatments aimed at reducing inoculum levels in the field include copper oxychloride and benomyl. Pre-harvest applications of benomyl are currently restricted if used on fruit destined for certain export markets. Isolates of Colletotrichum gloeosporioides collected during a three-year market survey were used to determine the incidence of resistance to benomyl, thiabendazole and prochloraz using an in vitro assay. A total of 17.7% of all isolates tested were resistant to benomyl, of which 8.5% were highly and 9.2% moderately resistant. Isolates from certain production areas were less sensitive to benomyl and thiabendazole, and mango isolates were generally more sensitive than avocado isolates. No isolates were resistant to thiabendazole or prochloraz. 相似文献
7.
Earthworms, Eisenia fetida, were treated by surface exposure to the fungicide benomyl at various stages of posterior segmental regeneration. Teratogenic effects of benomyl were observed when worms were treated 7–11 days after amputation (i.e. during the normal period of segmental replication), but not during days 1–5, 13–17, or 19–23. Teratogenic effects included a reduction in the number of regenerated segments, an increased frequency of segmental groove anomalies, and a variety of monstrosities. The effects of benomyl treatment on the number of regenerated segments and frequency of anomalies were dose-dependent within a narrow concentration range (approximately 0.2–5.0 mg litre?1); at higher concentrations (e.g. 25 mg litre?1) teratogenic effects were less frequent because the onset of segmental delineation was delayed until well after exposure. Non-invasive electrophysiological recordings from treated worms indicated that functional integrity of giant nerve fibre conduction pathways was established in all anomalously regenerated tail segments, except in a two-tailed monstrosity. The evidence supports the hypothesis that these teratogenic effects derive from an antimitotic mode of action of benomyl on segmental regeneration. 相似文献
8.
Junya Takahashi Osamu Kirino Chiyozo Takayama Shigeko Nakamura Hiroshi Noguchi Toshiro Kato Katsuzo Kamoshita 《Pesticide biochemistry and physiology》1988,30(3)
For 69 methyl N-phenylcarbamates having various benzene ring substituents, the fungicidal activity was determined against Botrytis cinerea resistant to benzimidazole fungicides by the agar medium dilution method. The structure-activity relationships were analyzed quantitatively using such physicochemical substituent parameters as hydrophobic π, steric B5, and HB (hydrogen bonding) with the Hansch-Fujita method (C. Hansch and T. Fujita, J. Amer. Chem. Soc.86, 1616 1964). The hydrophobicity of substituents was favorable to the acitivity. The effect was position-specific, the importance being in the order of ortho meta > para. The activity was related parabolically to the maximum width of one of the m-substituents having the larger dimension. The hydrogen acceptability of p-substituents enhanced the activity. The preventive activity of compounds against gray mold of cucumber caused by the resistant B. cinerea, which was determined by the foliar application in pot tests, was dependent on the magnitude of the fungicidal activity and hydrophobicity of the compounds as analyzed by the adaptive least-squares method. 相似文献
9.
Duane R. Romer Brian L. Aldrich R. Garth Pews Richard W. Walter 《Pest management science》1995,43(4):263-266
A series of eleven 1,4-dithiino[2,3-b]quinoxaline-2,3-dicarbonitriles was prepared by reaction of 2,3-dichloroquinoxalines with disodium (2)-2,3-dimercapto-2-butenedinitrile in N,N-dimethylformamide. These products were tested for in-vitro fungicidal activity by a Minimum Inhibitory Concentration (MIC) method. Several of these compounds showed broad-spectrum fungicidal activity. The activity exhibited by these compounds was greatly dependent upon the substituents of the quinoxaline ring, with the nitro-substituted derivatives showing the highest levels of antifungal activity. None of the compounds prepared, however, showed fungicidal activity comparable to that of the commercial fungicides screened. 相似文献
10.
The performance of carbendazim and its chemical precursors benomyl, thiophanatemethyl and methyl 4-(2-aminophenyl)-3-thioallophanate ( I ) ( “NF48” ) as systemic fungicidal seed treatments on barley was investigated. In field trials all treatments significantly decreased smut (Ustilago nuda) at 3.2 g kg-1 of seed; the order of effectiveness was I > benomyl > thiophanate-methyl > carbendazim. Control of barley mildew (Erysiphe graminis) followed a similar pattern but results were less clear-cut. Measurements of uptake and translocation from seeds, treated with radiolabelled fungicide and planted in pots of Woburn soil in a controlled environment room, showed that seedlings accumulated much more I than the other compounds over 28 days. This substantial early uptake into leaves could explain why I was particularly effective against smut in the field trials. Comparisons of amounts taken up. with solubility in water, octanol/water partition coefficient, extent of adsorption on soil and pKa values suggested that the effects of these properties on availability in the soil solution may be more important than their influence on penetration into the root in determining relative uptake and disease control in the case of localised applications such as seed treatments. 相似文献
11.
Christiane Stehmann Maarten A. De Waard 《European journal of plant pathology / European Foundation for Plant Pathology》1996,102(2):171-180
Sensitivity of field isolates (121) ofBotrytis cinerea from France (1992), Germany (1979–1992), Israel (1990) and the Netherlands (1970–1989) to the triazoles tebuconazole and triadimenol, the benzimidazole benomyl and the dicarboximide vinclozolin were tested in radial growth experiments. Resistance to benomyl (in 21 to 100% of isolates tested) and vinclozolin (in 25 to 71% of isolates tested) was common in most countries. EC50s (concentrations of fungicides inhibiting radial mycelial growth ofB. cinerea on B5-agar by 50%) for tebuconazole and triadimenol ranged between 0.01–1.64 and 0.4–32.6g ml–1, respectively, and were log-normally distributed. The variation factor (ratio between EC50s of the least and most sensitive isolate tested) amounts 164 and 82 for tebuconazole and triadimenol, respectively. These values are comparable to those for azole fungicides applied in control of other pathogens. Hence, variation in sensitivity to triazoles can probably not explain limited field performance of triazoles towardsB. cinerea. Isolates from south west Germany (1992) were significantly less sensitive to tebuconazole than isolates collected earlier in Germany, Israel and the Netherlands. Such less sensitive populations may contribute to the limited field performance of DMI fungicides towardsB. cinerea. The sensitivity of isolates from south west Germany to tebuconazole was similar to that of DMI-resistant mutants generated in the laboratory. These mutants displayed stable resistance with Q-values (ratio between EC50 of resistant mutant and wild type isolate) between 5 and 20. Sensitivity of field isolates and laboratory mutants to tebuconazole and triadimenol was correlated. 相似文献
12.
Elzbieta G. Magnucka Yoshikatsu Suzuki Arkadiusz Kozubek 《Pesticide biochemistry and physiology》2007,88(2):219-225
The content and homologue composition of alkylresorcinols were investigated in rye seedlings (Secale cereale L.) treated with benzimidazole fungicides and grown for 5 days under various thermal and light conditions. The fresh and dry biomasses of green and etiolated plants were greatly increased by benomyl and carbendazim at 29 °C. At 22 and 15 °C benomyl had an inhibitory action on growth of rye, whereas the effects caused in the presence of carbendazim were slightly dependent on external stimuli. On the other hand, benomyl enhanced resorcinol biosynthesis in green seedlings grown at all temperatures, while carbendazim only at 29 °C. In plants kept in the darkness, both fungicides increased content of alkylresorcinols at 29 °C and decreased its at 22 and 15 °C. The qualitative pattern of resorcinolic homologues was also significantly modified in the presence of benomyl and carbendazim and depended on other physical stimuli. 相似文献
13.
Earthworm populations in apple orchard plots sprayed with benomyl and thiophanate-methyl were greatly reduced. Lumbricus terrestris, a surface-feeding species, was not found in the treated plots. Captive worms would not feed on leaf material with spray deposits of benomyl, MBC and thiophanate-methyl at 1.75 μg/cm2, and feeding was significantly reduced when deposits were 0.87 μg/cm2. There was 100 % kill of worms in pots of soil within 14 days following a benomyl drench at the rate of 7.75 kg/ha, and a 60 % kill following a drench at the rate of 1.55 kg/ha. Worms immersed for 1 min in benomyl suspensions of 0.05 or 0.5 % died within 27 and 13 days respectively; those immersed in lower concentrations would not feed for 2 weeks but eventually did so. It is suggested that the lethal effects of benomyl may be due to anti-cholinesterase activity of the carbamate moiety of the molecule. 相似文献
14.
甜菜褐斑病菌对苯并咪唑类杀菌剂抗药性的研究 总被引：11，自引：0，他引：11
1980～1981年期间,自各地甜菜褐斑病病叶样本上分离出563个单孢菌株,并测定了各菌系对甲基托布津的敏感性。结果表明,山东高密、江苏东辛农场等地单独使用苯并咪唑杀菌剂3～4年以后,病菌产生了严重的抗药性,黑龙江巴彦、呼兰、山东薛城等地因没有或极少用药防治,病菌仍然表现敏感。山东菏泽、滕县等地已有一定数量的抗性菌株,但分布尚不普遍。试验证实,抗性菌株对甲基托布津、多菌灵和苯来特等三种苯并咪唑杀菌剂具有交互抗性,百菌清、醋苯锡和毒菌锡对抗性及敏感病菌均有良好效果。目前可选择百菌清作为苯并咪唑类的主要替换药剂。初步观察,停止用药后三年以内抗性菌株的数量及抗性程度仍然保持稳定。此外,甜菜频繁调种加速了抗性病菌的扩散。建议未发现抗性的地区应尽量避免从抗性严重的地区调种。 相似文献
15.
Anita Wengel Niels Jacobsen Hans Kolind-Andersen Poul Bjerregaard 《Pest management science》1990,30(2):223-233
Several thiosemicarbazones of 2-formyl- and 2-acetylpyridine dialkylated on N4 and non-alkylated on N2 were found to be broad-spectrum protectant fungicides with activity particularly against oomycetes. The effect of some of the compounds on chitin biosynthesis was studied, but the low inhibitory activity observed combined with the fungicidal activity spectrum—particularly the high activity against oomycetes—excludes this as their main mode of action. Attempts at enhancing the systemic properties of the compounds by chemical modifications failed. 相似文献
16.
为探索新的农药先导化合物,经取代苯基呋喃甲酰氯与5-羟基-3(2H)哒嗪酮反应,得到15个未见文献报道的含呋喃环3(2H)哒嗪酮类化合物,其结构均通过了红外光谱、核磁共振氢谱和元素分析确认。初步生物活性测定结果表明,目标化合物表现出良好的杀菌活性,其中化合物3i在50 mg/L时对灰霉病菌和纹枯病菌的抑制率分别为89.16%±1.73%和81.27%±1.38%,与对照药剂腐霉利(88.58%±1.64%和79.62%±1.15%)相当。初步的构效关系结果显示,苯环上取代基的种类和位置对杀菌活性有重要影响。 相似文献
17.
Proefstation N. A. M. Van Steekelenburg 《European journal of plant pathology / European Foundation for Plant Pathology》1978,84(1):27-34
The effect of a number of fungicides on mycelial growth ofDidymella bryoniae on agar was tested and compared with the effect on inoculated plants and in commercial crops. Activities in vitro and vivo are not always correlated. Spraying of inoculated young plants is a reliable and quick method for testing fungicides againstD. bryoniae.In commercial crops the treatments in decreasing order of effectiveness were weekly sprays of benomyl 0.025–0.05% active ingredient (a.i.), chlorothalonil 0.15% and triforine 0.02% a.i. These chemicals should be sprayed alternately to prevent the development of strains tolerant to benzimidazole derivates.Samenvatting Een aantal chemische middelen zijn in vitro en op verschillende manieren in vivo getoetst op hun werking tegenDidymella bryoniae. De resultaten in vitro zijn niet altijd positief gecorreleerd met die in vivo (Tabel 1 en 2). De resultaten na inoculatie van jonge plantjes komen wel overeen met die onder praktijkomstandigheden (Tabel 3, 4 en 5). Op jonge plantjes kunnen dus middelen op een snelle wijze en in een beperkte ruimte betrouwbaar worden getoetst.Onder praktijkomstandigheden werd het beste resultaat verkregen met benomyl 0,025–0,05% actieve stof, zowel wat betreft de gewas- als de vruchtaantasting. Hierop volgde chloorthalonil 0,15% a.s. en triforine 0,02% a.s. (Tabel 4 en 5). IndienD. bryoniae met chemische middelen moet worden bestreden, is het noodzakelijk dat er bijna elke week wordt gespoten (Tabel 5). Teneinde het ontstaan van resistentie van schimmels tegen benomyl en andere MBC-producerende fungiciden te voorkomen, wordt aanbevolen om benomyl, chloorthalonil en triforine afwisselend toe te passen. Met dit schema worden vele andere schimmelziekten in komkommer eveneens bestreden. 相似文献
18.
Micronutrients, applied to the soil in pot tests, differentially altered the efficacy of nine fungicides used as a seed treatment against cowpea seedling rot caused by Rhizoctonia solani. Boron improved disease control by 2-methoxyethylmercury chloride, quintozene, chloroneb and carboxin, but five other micronutrients reduced the efficacy of the fungicides to varying extents. NPK lowered the efficacy of all the fungicides tested except that of thiabendazole, but carbendazim and benomyl gave maximum disease control in soil treated with a mixture of six micronutrients and NPK. Implications of micronutrient-fungicide interactions are discussed in the context of fungicidal control of R. solani; probable mechanisms of inactivation of fungicides by micronutrients are indicated. 相似文献
19.
The primary evaluation of ten fungicides for the control of cucumber powdery mildew (Sphaerotheca fuliginea), tomato leaf mould (Cladosporium fulvum) and tomato grey mould (Botrytis cinerea) indicated that nine of them were systemically active against one or more of the pathogens when applied as soil drenches. Benomyl, thiophanate, thiophanate-methyl, thiabendazole and Cela W52A showed activity against all three diseases, but dimethirimol, triarimol and dodemorph were more specific and mainly active against cucumber powdery mildew. An in vitro bioassay generally indicated that fungitoxicity was not translocated from sprayed to unsprayed leaves, and though toxicity to B. cinerea, following soil drenches of benomyl, thiophanate and thiophanate-methyl, was detected by bioassay in leaf sap and calyces it was not detected in fruit. Furthermore, extended evaluation of benomyl for the control of grey mould on cropping tomotoes showed that in the presence of abundant B. cinerea inoculum, benomyl soil drench treatment effectively controlled flower and leaf infection but not fruit ghost-spotting. 相似文献
20.
Characterization of the mechanism of action of the fungicide fenpicoxamid and its metabolite UK‐2A 
下载免费PDF全文
下载免费PDF全文 David H Young Nick X Wang Stacy T Meyer Cruz Avila‐Adame 《Pest management science》2018,74(2):489-498