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1.
Brian D. Rennison 《Pest management science》1977,8(4):405-413
Poisons used in bait to control rats are of two kinds; single-dose acute poisons and those with a slow or cumulative action lethal only if two or more daily doses are consumed. The two types require different baiting techniques and different methods must be used for testing them in the field. For acute poisons, the relative sizes of rat infestations have to be measured by baiting with unpoisoned bait both before and after poison baiting and the pre-treatment sizes taken into account when analysing the results. When testing possible cumulative or multiple-dose poisons, pre-treatment baiting is unnecessary and the method used was that originally devised for field testing for anticoagulant resistance in rats. Examples of published results of field trials of both types of poison are discussed. 相似文献
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J. CASELEY 《EPPO Bulletin》1983,13(2):171-176
Weeds have relatively long life cycles and satisfactory control measures can often be undertaken over a longer period than those for many other pests. Consequently, emphasis has been placed on the effects of environmental factors on weed control and selectivity rather than on level of infestation. An overall view of the interaction of weather and herbicide performance may be obtained by considering field results and meteorological data, but in order to rank the importance of individual weather factors it is usually necessary to vary one environmental factor while the others are held constant From field experience it is generally accepted that certain weather criteria must be met for successful application results, but it is less widely appreciated that environmental factors before and after spraying may exert a major influence on herbicide activity. Results illustrate the way in which environmental factors influence spray interception and herbicide entry, movement and phytotoxic activity in the plant. The use of this type of information to increase herbicide reliability and flexibility of use is discussed. 相似文献
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Since the 1950s, pesticide resistance has been identified in many species. This paper considers the role of resistance action groups and notes that they were all formed in response to resistance problems occurring. Data now exist on the strategies which are most effective and the paper aims to bring together information from the fields of weeds, pests and diseases. Pesticide mixtures, sequences or rotations have been demonstrated as having a clear role in resistance management strategies. Resistance management would be improved if there was agreement on uniform test methodology and interpretation of results. The industry must work together to agree what constitutes an anti-resistance strategy, whether this is for prevention or cure, and to ensure that this is then included within regulatory frameworks. Future developments such as patch treatment, biotechnology and biocontrol are discussed. It is concluded that, to date, there has been little discussion between specialists in the field of resistance to herbicides, fungicides or insecticides and it is clear there are significant advantages to be had from more interaction. ©1997 SCI 相似文献
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In Austria, beneficial arthropods and entomopathogenic nematodes ('macrobials'), as well as micro-organisms and viruses, are classified as active substances of plant protection products, according to the Federal Law on Transactions with Plant Protection Products which entered into force in 1991. Therefore, naturally occurring organisms, intended for use in the field of plant protection, must be authorized as plant protection products before they are permitted to be sold. Requirements for the authorization of macrobials, micro-organisms and viruses and the authorities involved are presented. The legislative regulations for the use of macrobials, micro-organisms and viruses as plant protection products are described. At the beginning of 1996, 35 plant protection products containing 21 different organisms have been authorized in Austria for use in agriculture, horticulture and forestry. 相似文献
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Anne‐Sophie Walker Christiane Auclair Michel Gredt Pierre Leroux 《Pest management science》2009,65(8):906-915
BACKGROUND: Microdochium nivale (Fr.) Samuels & Hallet and Microdochium majus (Wollenweber) belong to the Fusarium ear blight (FEB) fungal complex affecting cereals. In 2007 and 2008, major Microdochium sp. infestations were observed in France, and the efficacy of strobilurins was found to be altered in some field trials. The aim of this study was to determine the sensitivity to strobilurins of French isolates of Microdochium and to characterise the possible mechanisms of resistance. RESULTS: Half of the strains collected in 2007 were resistant to strobilurins, and most also displayed strong resistance to benzimidazoles. Strobilurin resistance was found mostly in M. majus isolates. Positive cross‐resistance was observed between all strobilurins tested, but not with the phenylpyrrole derivative fludioxonil and the various classes of sterol biosynthesis inhibitors (SBIs). In most strains, resistance was correlated with the G143A substitution in cytochrome b, the molecular target of strobilurins. Two other mechanisms were also detected at lower frequencies. CONCLUSION: This is the first report of strobilurin resistance in Microdochium. Several resistance mechanisms have evolved independently in populations and may have different impacts on field efficacy. This makes the accurate detection and quantification of QoI resistance difficult. The management of field resistance and efficacy must be adapted to take these findings into account. Copyright © 2009 Society of Chemical Industry 相似文献
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K. SCHMIDT 《EPPO Bulletin》1996,26(1):117-122
In Germany, application of plant protection products by helicopter is only common in steep-sloped vineyards and in forests, where the use of conventional sprayers is nearly impossible. Because environment pollution, especially drift, is much higher than with ground equipment, the use of helicopters is subject to plant protection legislation as well as to air traffic regulations. BBA guidelines have been developed for application of plant protection products with aircraft. Each air-borne application must be based on a contract respecting these guidelines and must be reported to the proper authorities and announced to the public. The working airfields must be properly equipped and applications may only be performed under authorized weather conditions. The equipment of the aircraft must fulfil standards, especially for the spray tanks, the spray boom and the control devices, and so must the service stations on the ground. 相似文献
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Several ornamental and wild Prunus species have been identified as natural and/or experimental hosts for Plum pox virus (PPV). The significance of natural vs. experimental hosts, graft or bud-transmitted infections vs. aphid-transmitted infections in ornamental or wild Prunus hosts, and their relevance in the field situation, are not clearly understood. However, since PPV is aphid-transmitted, any host in the field or nursery serves as a potential reservoir and source of inoculum and must be monitored and controlled in any PPV eradication or management programme. 相似文献
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随着塔里木油田的开发，输油管道的建设提到了议事日程。在输油管道的建设过程中，会使生态环境受到影响。我们在进行库尔勒－鄯善段输油管道环境影响评价时，采用了经济评价的方法，尝试用货币的方式定量的计算生态破坏的大小。 相似文献
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The effect of trifluralin on the growth and development of cotton plants in low-organic-matter soils from the northern Negev of Israel was studied. Trifluralin exhibited linear sorp tion isotherms on these soils, Trifluralin and dinitramine losses from soils under varying moisture regimes and application practices were determined in open systems. The data were fitted to both first-order and biexponential kinetic equations. In about 50% of cases the biexponential kinetic model provided a better fit to the data, but no relationship could be found between the model parameters and environmental or soil properties. Losses were generally greater at field capacity than at 50% field capacity, and at 27°C than at 15°C, and in soils with a lower organic matter content. The trifluralin application rate was negatively correlated with vegetative growth parameters of cotton, but the correlation became weaker with increasing soil organic carbon content. Trifluralin delayed boll production in coarse textured soils, the longest delay occurring at higher application rates. It is concluded that in light soils that contain very little organic matter, trifluralin rates must be maintained at the minimum level required for adequate weed control to prevent damage to crops. 相似文献
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Starting in 1979 the pathogenicity of dicarboximide-resistant and sensitive strains of Botrytis cinerea was regularly examined in greenhouse tests using grape plants. In these tests the proportion of resistant strains with low or nearly no pathogenicity was always higher than that of sensitive strains. This led to comparative studies on the enzyme activities of sensitive and resistant field isolates. Pectolytic and cellulolytic enzymes were chosen because of their importance in the infection process of B. cinerea. The results of these studies indicated that no correlation could be found between the activity of these enzymes and the pathogenicity of the tested isolates, and that resistant strains tended to have higher enzyme activities than sensitive ones. Comparison of the enzyme activities of laboratory-adapted isolates and the original sensitive ones gave similar results. Since enzyme activities do not seem to play an important role in explaining the general observations on the slow increase and spread of resistant strains in vineyards, other factors must be considered, such as the stability of the dicarboximide resistance, which apparently is very low. 相似文献
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S. A. Ward R. J. Chambers K. Sunderland A. F. G. Dixon 《European journal of plant pathology / European Foundation for Plant Pathology》1986,92(3):127-132
Analysis of field samples of the aphidSitobion avenae on winter wheat revealed that the power-relation between mean density and between-tiller variance did not change during the seasonal growth and decline of the aphid population. A single equation, therefore, could be used throughout the season to calculate the optimal sample size — the number of tillers that must be examined to yield an accurate estimate of aphid density. 相似文献
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R. E. MARSH 《EPPO Bulletin》1988,18(2):293-299
The use of captive predators for testing potential secondary hazards of rodenticides is becoming an increasingly important research method. The usefulness of the test results depends on how realistically the test protocol corresponds to natural events and encompasses such factors as the selection of the predator species, sample sizes, methods of dosing the primary species, and the feeding regime of primary consumers to the predators. While such studies can provide excellent data, extreme care must be exercised in the extrapolation of such data to field situations. Some major shortcomings in such extrapolations are: (1) it is difficult under field conditions to know how much toxicant is actually consumed and the amount retained by the rodents; (2) it is even more difficult to determine the frequency and number of primary target animals consumed by predators over time. Test protocol development must of necessity be somewhat subjective, but a strong commitment should prevail to keep the methodology as realistic as possible. 相似文献
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Dale R. Walters 《European journal of plant pathology / European Foundation for Plant Pathology》2006,114(3):255-260
The ability of fungal pathogens to develop resistance to fungicides and to overcome genetic resistance in their hosts, coupled
with growing public concern for the environment, means that there is an urgent need for novel methods of disease control.
The leaf surface provides the first barrier that fungi must overcome in order to gain access to the leaf, but it also provides
chemical and physical cues that are necessary for the development of infection structures for many fungal pathogens. Film-forming
polymers can coat the leaf surface, acting not just as an extra barrier to infection, but also disguising the cues necessary
for germling development. Kaolin particle films can envelop the leaf in a hydrophobic particle film barrier that prevents
spores or water from directly contacting the leaf surface and as a result, can suppress infection. Adhesion of fungal spores
to the leaf surface, which is important to keep spores on the leaf surface and for appropriate development of the fungus on
the leaf surface, can be inhibited, leading to reduced infection and lesion development. Polymer and particle films have been
shown to provide disease control in the field, while research on agents that inhibit spore adhesion on leaf surfaces is still
in its infancy. There is an urgent need for research on the practicality of using these novel methods under field conditions
and on ways of integrating them into current crop protection programmes. 相似文献
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Current biological control strategies involve the use of exotic or native biocontrol agents, proven to be host-specific and lethal. This is a successful field of endeavor, attractive lo a large cadre of entomologists and a few plant pathologists. The main limitation is that each weed species must be attacked by a separate host-specific agent and these organisms are not always lethal. Only by using a radical paradigm shift can we reach a new strategy of biocontrol. In this strategy, lethal, broad host-range pathogens are genetically modified to permit their safe release. Either they are rendered host-specific or they are given a chemical dependency that prevents their spread or long-term survival. This genetic-manipulative approach offers numerous and diverse scenarios for biocontrol. Host-specific promoters or toxins, host-dependency by multiple auxotrophy, or mutants dependent on specific environmental conditions are all approaches that lend themselves to genetic modification. Such self-delimiting pathogens may have the advantage of repeated marketability, environmental safely and multiple target weeds. 相似文献
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沙漠油田基地路生物防沙试验段林木生长状况 总被引：6，自引：3，他引：3
对沙漠油田基地路生物防沙技术示范工程中不同立地条件下所种植的梭梭、柽柳、沙拐枣三类灌木的生长状况进行了调查，对盐水灌溉后各种立地类型的沙地土壤水盐状况进行了取样分析。研究结果表明：在塔中沙漠油田基地路生物防护体系建设的过程中，在沙丘和平沙地上应选用沙拐枣和梭梭，如种植柽柳则需采取适当的土壤保水措施（如在种植坑内加施草碳、固水剂、粘土等）。在含有下伏亚粘土层的沙地上应选用柽柳和梭梭，在丘间板结沙地上要想营造防护林，必需采取适当的技术措施，使土壤疏松（如深开沟、回填流沙等）。 相似文献
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石油农业抑或生态农业——关于开发大西北问题的思考之一 总被引：1，自引：0，他引：1
夏伟生 《干旱区资源与环境》1987,(2)
本文在分析石油农业的弊端和生态农业优越性的基础上,提出我国开发大西北过程中在农业生产方面,必须坚持生态农业的方向。为了使西北地区生态农业建设卓有成效,在指导思想上要注意以下几点:1、重点要放在内涵性发展而不是外延性发展上;2、把有机农业和无机农业结合起来,综合为物质和能量良性循环的农业;3、实行专业化与多种经营相结合的方针;4、吸收新技术革命的成果来推动生态农业的建设。 相似文献
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Advances in bioherbicide formulation 总被引：1，自引：0，他引：1
Formulation of a bioherbicide ideally should result in a product that has low cost, long shelf-life, ease of application and efficacy. Formulation persists as a constraint to commercial development of many potential bioherbicides often because dew dependence in fungi limits their efficacy under dry-land conditions. This has not been a problem with several commercial bioherbicides because they are used in irrigated systems or applied as wound inoculations. Thus, reduction in dew dependence is a principal aim in the formulation of many potential bioherbicides. In the present paper, formulation research attempting in part to overcome this problem via the development of novel solid and liquid formulations is described. Solid formulations typically must be able to survive in the field and await suitable conditions before becoming activated. Liquid formulations have the potential to produce infections soon after application provided they remain moist on the target plant surface. Several attempts to improve water-holding capacity in liquid formulations have been examined. The use of multiple emulsions of water in oil in water has recently shown promise. 相似文献