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R. L. Wastie 《国际虫害防治杂志》2013,59(3):268-288
Abstract Most of the major diseases of Hevea brasiliensis are of worldwide distribution (with the notable exception of South American leaf blight, against which strict quarantine regulations are enforced by rubber-growing countries outside the Americas to prevent the unauthorised import of Hevea) but their local severity and importance vary from one region to another. Root diseases are a serious problem nearly everywhere and regular rounds of inspection and treatment are essential while the trees are still young in order to prevent serious losses. The recently introduced prophylactic collar protectant dressings specific to each of the three main diseases are valuable aids to control. Diseases of the tapping panel may prevent tapping or hinder bark regeneration; black stripe in particular (Phytophthora palmivora) can be very persistent and is often eradicated only by repeated therapeutic fungicidal treatment of the bark. Stem diseases, chiefly pink disease (Corticium salmonicolor), are important in certain areas in wet weather, and can lead to severe damage and even dieback in the absence of effective treatment. Four major leaf diseases can have a debilitating effect on the tree. Abnormal leaf fall (Phytophthora spp.) is severe in India, causing the abscission of mature leaves during the monsoon rains; treatment necessitates the application of a pre-monsoon prophylactic copper spray. Secondary leaf fall, caused both by Oidium heveae and Colletotrichum gloeosporioides which infect the flushes of new leaves produced after the annual leaf change (wintering), varies greatly in severity according to local weather and cultivar. It can be controlled by repeated rounds of an appropriate prophylactic fungicide or, under certain conditions, by artificially hastening the onset of wintering (and thus of refoliation) by removing the old leaves with a contact herbicide. By far the most important leaf disease is South American leaf blight (Microcyclus ulei); it is largely responsible for the lack of a vigorous rubber industry in South America, the home of the rubber tree. It can only be effectively countered by the use of resistant cultivars. The economic importance of the above diseases is discussed and current control measures described. 相似文献
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Peter Jeschke 《Pest management science》2016,72(2):210-225
The synthesis of propesticides is an important concept in design of modern agrochemicals with optimal efficacy, environmental safety, user friendliness and economic variability. Based on increasing knowledge of the biochemistry and genetics of major pest insects, weeds and agricultural pathogens, the search for selectivity has become an ever more important part of pesticide development and can be achieved by appropriate structural modifications of the active ingredient. Propesticides affect the absorption, distribution, metabolism and excretion parameters, which can lead to biological superiority of these modified active ingredients over their non‐derivatised analogues. Various selected commercial propesticides testify to the successful utilisation of this concept in the design of agrochemicals. This review describes comprehensively the successful utilisation of propesticides and their role in syntheses of modern agrochemicals, exemplified by selected commercial products coming from different agrochemical areas. © 2015 Society of Chemical Industry 相似文献
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There are many natural enemies of weedy plants; among them are plant pathogens. Plant pathogens are capable of affecting plants,
in part because of the phytotoxins they produce. Phytoloxins of weedy pathogens are produced in culture media by most of the
phytopathogenic fungi of weeds that we have studied. In most cases the phytotoxin(s) usually belongs to a family of related
compounds produced by the pathogen. Phytotoxin production in the medium can be optimized by placement of the host extract
into the medium. Lethal activity is usually observed in the concentration range of 10-3-10-6M. The concept of using these molecules, or derivatives thereof, or related compounds as herbicides, should be explored. 相似文献
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张德鹏 《干旱地区农业研究》2007,25(6):249-252
国内外绒山羊品种95%以上分布于旱区,而又以干旱、半干旱和荒漠为主产区.在对绒山羊所处旱区特殊生态条件分析后,以表列方式简明扼要地将世界18个专门化绒山羊品种的种质特性与种用价值作比较,并对不同类型绒山羊品种的选育提高和进一步开发利用提出五项建议. 相似文献
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Deepwater rice has a distinctive pest complex due to prolonged deep flooding, extended growth duration and a complex environment. Flooding smothers weeds, prevents population buildups of some pests and diseases, and stimulates new growth which may compensate for early damage. Major pests are adapted to these aquatic conditions and exploit the succulent growth and mild weather extremes of this period.In Asia, yellow stem borer causes widespread damage by producing a loss of bearing stems, and lighter or empty panicles. No appropriate measures are known and control of this major pest is a daunting challenge. Stem nematode severely damages rice in several areas but varietal resistance is effective. Rats and hispa beetle are also injurious and many lesser pests are known. In West Africa's smaller Deepwater rice area, stem borers, leafeaters, birds and rats are damaging but their effect on yield is obscure. Farmers commonly employ cultural control methods, and insecticides are used in some areas but diseases are not treated. Pesticide use is restricted by application difficulties, contamination concerns and the low value of the crop. In Asia and Africa wild rices, grasses and sedges compete fiercely with rice before flooding; herbicides are not generally used but many farmers hand weed though the extent of yield loss is poorly understood.Pest management research in deepwater rice is difficult because of the nature of the agroecosystem. Most research has been carried out in Asia but the volume has seriously declined over the last decade. 相似文献
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甘蔗是最重要的糖料作物,由于其栽培过程中采用种茎无性繁殖,病毒病发生逐年加重.已知侵染甘蔗的病毒种类有甘蔗花叶病毒(Sugarcane mosaic virus,SCMV)、高粱花叶病毒(Sorghummosaic virus,SrMV)、甘蔗线条花叶病毒(Sugarcane streakmosaic virus,SCSMV)、甘蔗黄叶病毒(Sugarcane yellow leaf virus,SCYLV)、甘蔗斐济病病毒(Sugarcane Fiji disease virus,SFDV)、甘蔗线.条病毒(Sugarcane streak virus,SSV)和甘蔗杆状病毒(Sugarcane bacilliform virus,SCBV).文中简要介绍上述几种病毒的基本特性及其所致病害的发生特点,对目前甘蔗病毒病防治技术进行了评述,提出了我国甘蔗病毒研究中需要关注的若干问题. 相似文献
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植物源农药及其安全性 总被引：37，自引：4，他引：37
应用高科技手段从植物体提取和寻找植物体产生的对有害生物具有特异性抑制作用的物质 ,用于防治植物病虫害 ,使植物源农药的研究、开发利用开拓了广阔前景 ,对植物源农药的安全性和环境相容性的评估要求也更加严格。 相似文献
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Arbuscular mycorrhizal fungi (AMF) form symbioses with the majority of plant species and can provide multiple benefits to the host plant. In agro‐ecosystems, the abundance and community structure of AMF are affected by agricultural management practices. This review describes and discusses current knowledge on the effects of inorganic and organic chemical pesticides on AMF in the conflicting area between agricultural use and environmental concerns. Variable effects have been reported following chemical pesticide use, ranging from neutral to positive and negative. Moreover, a species‐specific reaction has been documented. The reported effects of pesticides on arbuscular mycorrhizal symbiosis are very diverse, and even when the same substance is investigated, the results are often contradictory. These effects depend on many parameters, such as the active substance, the mode of action, the mode of application and the dosage. In the field, determinants such as the physico‐chemical behavior of the active substances, the soil type and other soil microorganisms contribute to the fate of pesticides and thus the amount of active substances to which AMF are exposed. This review highlights that the fate of AMF following pesticide use needs to be addressed in a broader agro‐ecosystem context. © 2018 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. 相似文献
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BACKGROUND: The purpose of this work was to determine residues of acaricides in recycled Spanish beeswax. RESULTS: Chlorfenvinphos, fluvalinate, amitraz, bromopropylate, acrinathrin, flumethrin, coumaphos, chlorpyrifos, chlordimeform, endosulfan and malathion residues were determined by GC‐µECD/NPD/MS detection. Owing to the extreme instability of amitraz, this analyte was transformed into the stable end‐metabolite 2,4‐dimethylaniline, later derivatised with heptafluorobutyric anhydride and determined by GC‐µECD/MS. Recoveries from spiked samples ranged from 86 to 108%, while quantification limits varied from 0.10 to 0.30 mg kg?1 using GC‐µECD/NPD, and from 12 to 85 µg kg?1 by GC‐MSD. Of a total of 197 samples analysed, only eight samples (4%) were free of residues of chlorfenvinphos (0.019–10.6 mg kg?1), fluvalinate was present in 93.6% of samples analysed (0.027 –88.7 mg kg?1), while coumaphos was confirmed in only five of the 134 samples analysed at concentrations of less than 195 µg kg?1. The remaining acaricides were identified with different levels of incidence at concentrations from 12 to 231 µg kg?1. CONCLUSIONS: Residues of acaricides were found in an extensive number of beeswax samples. The contamination with chlorfenvinphos and tau‐fluvalinate was very relevant, particularly as chlorfenvinphos is not legally authorised for use in beekeeping. The possible impacts of the main acaricides detected on larval and adult honey bees are discussed. Copyright © 2010 Society of Chemical Industry 相似文献
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分别采用菌丝生长速率法和盆栽法,测定了一系列菲并吲哚里西啶生物碱及其盐衍生物的杀菌及除草活性。结果表明:该类生物碱及其盐衍生物表现出了很好的杀菌活性,尤其是生物碱安托芬 ± )-antofine]( 2 )和脱氧娃儿藤宁碱 ± )-deoxytylophorinine]( 3 )在50 μ g/mL下,对番茄早疫Alternaria solani、花生褐斑Cercospora arachidicola、苹果轮纹Physalospora piricola 和黄瓜枯萎Cladosporium cucumerium 4种菌体的抑制率达70%~100%;但未表现出明显的除草活性。 相似文献
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茭白是我国重要的特色水生蔬菜之一,对于丰富菜篮子和提高农民收入起到重要作用。随着大规模的人工栽培,茭白病害日益成为影响茭白产业发展的严重问题。然而,生产中经常存在不能正确使用茭白病害及其病原菌名称的问题,影响了对病害的识别与防治。这是由于不同研究者对病害认识的侧重点不同,导致同一病害在不同国家或地区具有不同的名称;而随着人们对病原菌认识的不断深入,引起病原菌分类地位的不断变化,也使同一种病原菌在分类史上出现不同的名称。正确使用病害及其病原菌名称,可提供病害特征及其病原菌生物学特性的信息,这对指导病害识别与防治尤为重要。本文系统介绍了茭白病害及其病原菌,尤其从病原菌分类史上说明病原菌名称演变的原因以及最新研究进展,为理解和正确使用病原菌名称提供了参考依据。同时,结合我们的研究工作,展望了茭白病害和病原菌未来研究和发展的趋势,提出了潜在病原菌可能传播的植物检疫问题。 相似文献
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B. H. Boelema 《European journal of plant pathology / European Foundation for Plant Pathology》1985,91(4):189-202
Theories on the relationships between the challenge dose of phytopathogenic bacteria and the quantal response of the host plant are discussed and applied to experimental results. In a number of cases the extent of disease was directly proportional to the dose, which is an indication of independent action. Departures from linearity in the relationships were ascribed tointer alia a shortage of multiplication sites, antagonism amongst the cells of the pathogen and heterogeneity of the tested host plants with respect to susceptibility. In a few host-pathogen combinations, dose-response relationships showing an upward curve were found; this is probably an indication of facultative synergism. The relationships found in homologous and heterologous host-pathogen combinations were similar. The implications of the above findings for the quantitative study of factors affecting the susceptibility of plants to bacterial infection are discussed.Samenvatting Na een bespreking van de theorieën over de relatie tussen het aantal fytopathogene bacteriën per inoculatie en de al-of-niet respons — waarbij dus de grootte van de individuele respons niet in acht genomen wordt — worden deze theorieën getoetst aan de resultaten van proeven die in de literatuur beschreven zijn. Onderschied wordt gemaakt tussen proeven waarin de proporties en die waarin de aantallen geslaagde inoculaties bepaald zijn. Verder is een vergelijking gemaakt tussen homologe en heterologe combinaties van waardplant en pathogeen.Waar de proporties geslaagde inoculaties werden gemeten, vond ik in een aantal gevallen evenredigheid tussen dosis en respons, mits een transformatie werd toegepast voor veelvoudige infectie. Dit is een aanduiding dat de cellen van het pathogeen elkaar niet beïnvloeden. Afwijkingen van dit rechtlijnig verband kunnen o.a. worden toegeschreven aan antagonisme tussen de cellen van het pathogeen, aan heterogeniteit in vatbaarheid van de waardplanten of aan een beperkt aantal vermeerderingsloci.In drie gevallen werd een naar boven gekromde lijn gevonden, hetgeen waarschijnlijk wijst op facultatief synergisme.In proeven waarin de aantallen geslaagde inoculaties gemeten werden, vond ik in de literatuur evenredige en dus rechtlijnige verbanden met afbuigingen naar rechts voor responses tot te hogere doses. De afwijkingen van rechtlijnigheid kunnen hier worden toegeschreven aan een beperkt aantal vermeerderingsloci of aan antagonisme tussen de cellen van het pathogeen.Geen essentieel verschil in dosis-respons verhoudingen werd gevonden tussen homologen en heterologe waardplant-pathogeen combinaties.De implicaties van bovengenoemde resultaten voor de kwantitatieve studie van factoren die de vatbaarheid van planten voor infectie door bacteriën bepalen, worden besproken. 相似文献
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N. LODOS 《EPPO Bulletin》1981,11(2):29-32
The commonest and most important species of Aelia in Turkey is A. rostrata. It is a primary pest, especially in Central Anatolia. Two other species, namely A. acuminate and A. syriaca , are secondary pests which damage wheat to some extent. The other species so far known from Turkey are of minor importance. 相似文献
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Relationships between their activities as blast control agents, and their abilities to inhibit mycelial melanisation on a nutrient agar, are described for 103 substituted benzothiazol-2(3H)-ones, benzoxazol-2(3H)-ones, indolin-2-ones, quinolin-2(1H)-ones, 1,2,3,4-tetrahydroquinolin-2-ones, benzo-1,4-thiazin-3(2H)-ones and benz-1,4-oxazin-3(2H)-ones, and some corresponding thiones. Several compounds in the respective series had a high protective activity and an antimelanisation activity against the blast fungus Pyricularia oryzae; furthermore, there was a good correlation in both of these activities, indicating that these compounds belong to the group of melanin biosynthesis inhibitors. Structural similarities of these compounds can be identified as follows: (a) having a benzo-bicyclic ring system; (b) containing a nitrogen atom in one ring at a position alpha to the benzene ring system; and (c) substitution, at the ring nitrogen atom, at the peri position in the aromatic ring relative to the nitrogen atom, and at the position alpha to the nitrogen atom in the ring system, with a double bond such as in carbonyl and thiocarbonyl groups. Among the compounds that have been proposed as melanin biosynthesis inhibitors, the chemical structures of tricyclazole, pyroquilon, 4,5-dihydro-4-methyltetrazolo[1,5-a]quinazolin-5-one (PP-389), [1,2,4]-triazolo[4,3-a]quinoline and 1-methylquinolin-2(1H)-one exhibit the structural similarities described above; however, 4,5,6,7-tetrachlorophthalide, 2,3,4,5,6-pentachlorobenzyl alcohol and N-substituted-2,3,4,5-tetrachloro-6-(hydroxymethyl)benzamides do not have such similarities in their chemical structures. 相似文献
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Species of entomophthoraceous fungi attacking insects and mites are very well represented in Israel. In the last decade, 22 species ofEntomophthora sensu stricto, Triplosporium, Zoophthora, Conidiobolus, and others under the designationEntomophthora sensu lato, have been identified, of which three are new species:Entomophthora turbinata, Zoophthora erinacea andZ. orientalis. Fiftyfour host-pathogen combinations hitherto not recorded in Israel are listed, of which 19 insect species are new hosts of entomophthoraceous species anywhere. 相似文献
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