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Colin Berry 《Pest management science》2020,76(9):2874-2877
This commentary does not concern itself with the need for, or the value of glyphosate as an agrochemical: rather it examines the scientific basis for the various conclusions reached at different times by a number of regulatory authorities and by the International Agency on Research on Cancer (IARC). Why do they differ? An appropriate regulatory stance depends critically on the application of good science and consistency in the application of established criteria. Constant reappraisal of the methodology used is essential. © 2020 The Author. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. 相似文献
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H. R. Shuyler 《国际虫害防治杂志》2013,59(4):445-451
Abstract Twenty four varieties of cowpea were evaluated for field resistance to Aphis craccivora Koch under natural infestation at Ile‐lfe, Nigeria. The varieties EW/1, TVu 1037, TVu 2896, TVu 2994 and TVu 3000 showed the lowest field infestation. This may be explained by antixenosis with respect to varietal selection or feeding and antibiosis. Screenhouse studies showed that the mechanism of resistance in TVu 1037, TVu 2896 and TVu 3000 includes antibiosis, manifested as high mortality of nymphs, reduced lifespan and low fecundity of adults. 相似文献
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D. R. Tracy 《EPPO Bulletin》2009,39(2):161-167
Phytophthora ramorum and P. kernoviae were first identified in Great Britain (GB) in 2002 and 2003 respectively, although both are believed to have been present for perhaps 10–20 years. Public gardens have been badly affected by these pathogens, but British woodlands are also considered at risk as a number of tree species have been found to be susceptible to the pathogens. The principal host of both Phytophthoras in GB is Rhododendron ponticum , which is arguably our most invasive weed species. It is found extensively in GB, especially along the west coast which has ideal climatic conditions for its growth and spread. In 2004 the Forestry Commission surveyed 1479 woodlands where R. ponticum was present, and in 2008 both infected and non-infected R. ponticum were cleared from approximately 1200 ha of woodlands in England and Wales where P. ramorum had been found. No clearance to date has taken place in Scotland. In the case of a positive finding in a garden or woodland, all woodlands with rhododendron within a 3 km radius of such a finding are to be surveyed. As both pathogens are notifiable any positives must be eradicated or contained through the serving of an official phytosanitary notice. Ministerial approval has now been given to a joint Defra and Forestry Commission initiative to undertake inter alia the removal of host plants (primarily rhododendrons) infected with these sporulating pathogens in woodlands and the wider environment in England and Wales. A similar programme will be effected in Scotland where the Forestry Commission is working with the Scottish Government's Rural Payments and Inspections Directorate. 相似文献
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荒漠化监测与评价指标研究进展 总被引：1，自引：0，他引：1
适宜的指标体系是高效开展荒漠化监测与评价工作的关键。文中从地面调查和遥感监测两个方面综述了荒漠化监测与评价的指标体系。地面调查的指标体系一般从三个层次上构建:以单一植被盖度指示荒漠化,综合植被、气候、土壤、土地类型等监测荒漠化状态,基于"压力-状态-响应"理论框架系统构建荒漠化监测与评价体系。遥感监测与评价指标主要包括多期影像分类指标、植被参数和土壤参数三个方面。最后总结当前研究中存在的问题,并提出了"多类型-多尺度-多维度"的荒漠化监测与评价指标框架,可为遥感与地面相结合的多类型和多尺度荒漠化过程监测与评价提供科学参考。 相似文献
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From horticulture and biofuel to invasion: the spread of Miscanthus taxa in the USA and Europe 
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下载免费PDF全文 Species of the genus Miscanthus (Poaceae) have recently become widely planted for ornamental and industrial uses. Yet these large perennial grasses have several traits that suggest a high invasion potential. To inform the debate on the benefits and risks of introducing these new biofuel crops, this publication summarises the invasion of Miscanthus species in Europe and the USA. Databases from North America were interrogated, and occurrence data from a variety of European sources were examined. In both continents, M. sinensis and M. sacchariflorus have recently spread rapidly, although invasion started earlier in the USA and both species are more widespread there. Both species mostly colonise grasslands and ruderal habitats. In addition, some escapes of the hybrid M. × giganteus, which has a particularly strong invasion potential because of its vigorous growth and greater capacity to establish in cool climates, have already been recorded. We conclude that the invasion potential of Miscanthus species needs to be thoroughly tested, the incipient invasions in Europe and the USA monitored and, if required, planting restrictions should be adopted. 相似文献
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Supplementing the diet of Coeloides scolyticida, Dendrosoter protuberans and Ecphylus silesiacus (Hymenoptera: Braconidae) with Parker's diet and the nectars of melliferous plants: Daucus carota L., Sinapis alba L. and Stachys recta L. had a significant effect on longevity, reproduction, developmental rate, and parasitizing of Scolytus scolytus (Fab.), Scolytus multistriatus (Marsh.) and Scolytus pygmaeus (Fab.) (Coleoptera: Scolytidae). These values were considerably lower for wasps fed with the nectar of Sinapis arvensis L. and Trifolium repens L. and the lowest for those without dietary additives. Parker's diet had the most significant effect on the parasitoids and parasitizing of the bark beetles. Nectar of S. recta and S. alba proved most suitable for C. scolyticida and D. protuberans, while E. silesiacus using the nectar from D. carota flower significantly increased parasitizing of S. pygmaeus. T. repens flowers were not a suitable additive for the diet of parasitoids. The parasitoids without additives in their diet had shorter lives, shorter development, and were less effective in reducing host numbers. E. silesiacus wasps had the longest development, and C. scolyticida the shortest. Generally, the parasitoids of the second generation had a slightly prolonged development (1–2 days). 相似文献
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Samuels GJ 《Phytopathology》2006,96(2):195-206
ABSTRACT A chronology is presented that charts the development of a genus and species concept in Trichoderma. Eighty-nine species of Trichoderma have been named, and several species of Hypocrea have been linked to unnamed Trichoderma anamorphs. Eighty-three taxa of Trichoderma and their teleomorphs, Hypocrea spp., have been included in phylogenetic analyses, including 11 species of Hypocrea with unnamed Trichoderma anamorphs. Phylogenetic analyses show that Trichoderma and Hypocrea are congeneric. Trichoderma species not linked to Hypocrea teleomorphs are derived from among species that are linked to teleomorphs, indicating sexual and asexual lineages are not independent of each other. Many more species remain to be discovered and described. Molecular phylogenetic analyses have revealed the existence of more species than have been recognized on the basis of morphology alone. A suggestion is made to modify the International Code of Botanical Nomenclature to enable adoption of a single generic name for Trichoderma/Hypocrea, with Trichoderma being the older and more utilitarian name. As increasing numbers of species are studied, the few morphological characters of anamorph and teleomorph have reached their limit for defining species. DNA-based characters have assumed an indispensable role. Exploration of new niches, such as within tree trunks and new geographic locations, have resulted in a substantial increase in the number of species of Trichoderma. Trichoderma is usually considered a genus of free-living soil fungi but evidence suggests that Trichoderma species may be opportunistic, avirulent plant symbionts as well as parasites of other fungi. Members of the genus Trichoderma are universally present in soils, although individual species may be either cosmopolitan (e.g., T. harzianum) or limited (e.g., T. viride) in their geographic distribution. To facilitate identification of species, a list of correctly identified strains of Trichoderma and their GenBank numbers for sequences of translation-elongation factor EF-1alpha and internal transcribed spacer rDNA is provided. 相似文献
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美国俄勒冈大学植物保护综合中心 Kogan博士在 1998年美国昆虫学年评 (Annu.Rev.Entomol.)上发表了这篇评论 ,详尽介绍了世界上 IPM(害虫综合治理 )的历史背景和当代发展。我们将此文译成中文 ,希望从事植保工作的教师、研究人员及有关领导部门能够从中有所收获。 相似文献
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The toxicity of several juvenile hormone analogs (JHAs) to susceptible and insecticide-resistant housefly (Musca domestica L.) strains was determined by an assay procedure in which larvae were exposed to residues of JHAs in glass vials. All JHAs tested were toxic and the most active compound, isopropyl 11-methoxy-3, 7, 11-trimethylododeca-2, 4-dienoate, was 100 times as toxic to the susceptible Orlando Regular strain as methyl parathion and 600 times as toxic as DDT.A 5- to 30-fold tolerance to the different JHAs was present in an insecticide resistant strain in which resistance is associated with a high level of NADPH-dependent microsomal oxidase activity controlled by a gene(s) on chromosome II. Cross-resistance was less marked in a strain with a chromosome V high oxidase gene and absent in strains with other resistance mechanisms.The data indicate that cross-resistance to JHAs in insects may occur in certain strains with high levels of oxidative detoxifying activity. Even so, the most active JHA was far more toxic to both susceptible and resistant strains than methyl parathion or DDT. 相似文献
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U &#;ILC S VRBNI&#;ANIN† D BO&#;I&#;† A &#;ARNI & Z DAJI&#; STEVANOVI&#;† 《Weed Research》2009,49(6):602-612
Surveys of weed vegetation of the western Balkan peninsula (1939–2006) were used to study changes in species composition. A large data set of arable weed vegetation was compiled and analysed with direct and indirect ordination, regression and beta (β) diversity analysis. Five environmental variables (altitude, season, year, crop, phytogeographical region) were used to determine broad-scale changes in weed species composition. The most important parameter was phytogeography and the second was crop. Altitude and season were found to be less important, although significant, which contrasts with results from Central and Northern Europe. β-diversity was higher in cereals and in summer, while decline along the altitudinal gradient previously demonstrated in Central Europe, was not observed. In southern parts of the studied area, thermophilous species have shifted to higher altitudes. The results and ranking of importance of environmental and spatial variables are discussed in relation to similar studies in Northern and Central Europe. 相似文献
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The capacity to react quickly to species introductions and to plan effective management countermeasures is always difficult, and methodology is lacking. This paper summarizes the different steps of a decision-making protocol applied to the recent establishment of an exotic species, the House Sparrow Passer domesticus, in the Lesser Antilles. This pest bird damages crops, fruits and stored food products and also competes with numerous hole-nesting birds in a large part of its range, and this requires more or less rapid management decision to limit its impact. In order to construct a base for decision-making in the Lesser Antilles case, we designed and conducted a brief biological study involving three spatial scales. At the regional scale, we defined the state of spread of House Sparrows throughout the West Indies. At the island scale, we estimated the number and distribution of breeding colonies. At the local scale, we estimated the numbers and behaviour of House Sparrows. To enable a quick decision to be made, we also suggested organizing a collective decision-making process applying a multi-actor guideline taking account of the different kinds of actors and levels of competence. We applied this method and we presented our results to a multi-actor workshop. The collective decision-making chose to apply the precautionary principle on one island (bird eradication) and to install both communications and monitoring plans. The procedure involving both multi-spatial scale assessment and a multi-actor workshop needs to be refined but its prospects are promising. 相似文献
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Linking water and nutrients through the vadose zone: a fungal interface between the soil and plant systems 总被引：1，自引：0，他引：1
Michael F ALLEN 《干旱区科学》2011,3(3):155-163
Plant water availability, use, and management have largely focused on physical processes of infiltration and the role of roots in uptake and transpiration. However, roots and mycorrhizal fungi redistribute water in complex patterns. Here I describe some of our observations and experiments showing that mycorrhizal fungi play key roles in moving water for both transpiration and to facilitate nutrient acquisition under dry conditions. Mycorrhizal fungal hyphae grow from both surface and deep roots even into bedrock to help extract water under dry conditions. In both deep and surface roots, mycorrhizal fungi acquire water from pores too small for roots and root hairs to access, and at distances from roots and root hairs. Mycorrhizal fungi are also able to utilize hydraulic-lifted water from plants to obtain nutrients in extremely dry surface soils. The importance of these root symbionts in water and nutrient dynamics, and as integrators of surface and deeper water dynamics need further investigation. 相似文献
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Liliya A DIMEYEVA 《干旱区科学》2013,5(4):439-451
The northeastern coast of the Caspian Sea is one of the youngest territories for plant colonization in Kazakhstan,and the flora of the most recent portion of this coastal area,the New Caspian marine plain,was chosen to study phytogeographical characteristics of plant species,especially as related to alien origin and invasive potential.Because of the recent formation of this flora,I expected that a large proportion of the species may be alien and invasive.After compiling a comprehensive species list from previous research,I identified the taxonomic,life form,ecological,and geographical structures of the flora.The area belongs to the northern type of deserts with continental climate and low annual precipitation.Taxonomic and life form structures show that the flora is specific to Central Asian deserts.Ecological structure demonstrates a high percentage of halophytes,which resulted from their adaptation to soil salinity and shallow ground waters that occur throughout the study area.Geoelements of the flora indicate allochtonous properties of the flora(i.e.species derived from areas outside the study area) with a low proportion of native(Caspian) plants.Alien species are estimated to comprise 12%-19% of the flora.Although some species have invasive features,severe arid environmental conditions and high salinity of soils and ground waters decrease invasive capacity of exotic plants.However,a threat of expansion of potentially invasive plants exists in the New Caspian marine plain due to the fast growth of anthropogenic habitats associated with recent oil developments. 相似文献
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China and the origins of Dutch elm disease: an appraisal 总被引：3，自引：0，他引：3
C. M. BRASIER 《Plant pathology》1990,39(1):5-16
Circumstantial evidence has led to the widespread assumption that Dutch elm disease (caused by Ophiostoma ulmi ) spread to Europe and North America from China. The author's recent surveys indicate that the disease is probably absent from China, and only a relatively recent arrival in the Soviet Tien Shan mountain region on the western Chinese border. Alternative origins for the disease include introduction from the Himalayas, and recent rapid evolution within Europe from a fungus such as Ophiostoma piceae . Elucidation of the various possibilities is complicated by the need to account for the spread of at least three genetically divergent subgroups of the pathogen. 相似文献
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Resistance to many insecticides demonstrated by the beet armyworm,Spodoptera exigua (Hübner), can be caused by the action of carboxylamidases. A colorimetric method, based on the hydrolysis of 4-nitroacetanilide to 4-nitroaniline by carboxylamidases, was used for evaluating biochemical properties of these detoxifying enzymes in beet armyworm. The optimum pH and temperature were 7.5 and 38°C, respectively. Km (Michaelis constant) and Vmax (maximal velocity) at 28°C were 2.3 X 10-4 M and 2.06 nmol min-1 mg protein-1, respectively. The enzyme activity was evaluated in several body parts and located mostly (66.2%) in the midgut. The soluble fraction (supernatant of 105,000g) contained the highest enzyme activity relative to the total (69.3%), and exhibited the highest specific activity. Carboxylamidase activity was totally inhibitedin vitro at a concentration of 10-6 M methomyl. The analysis of thein vitro inhibition kinetics indicated the ability of methomyl and diflubenzuron to inhibit carboxylamidases noncompetitively. Over 95% inhibitionin vivo was obtained when the larvae were fed with castor bean leaves dipped in 250 mgl -1 of methomyl. Thein vivo enzyme activity could be reduced to half with a pretreatment of 15 mgl -1 diflubenzuron. 相似文献