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41.
The optimal conditions required to market Trichoderma as a biocontrol agent against soilborne fungi and nematodes are discussed. These include a proper formulation, an efficient delivery system, and alternative methods for Trichoderma's application.The implementation of Trichoderma in integrated pest management (IPM) can be achieved using a soil treatment which combines reduced amounts of biocides/fungicides and the Trichoderma preparation. Biocontrol activity can be increased by combining two (or more) types of biocontrol agents. Moreover, the construction of a genetically modified Trichoderma can lead to the improvement of certain traits which are absent or not highly expressed in the native microorganism isolated from its natural habitat.Different Trichoderma harzianum and T. lignorum isolates were tested for their nematicidal activity against the root-knot nematode Meloidogyne javanica. In short-term experiments, improved growth of nematode-infected plants and decreases in the root-galling index and the number of eggs per gram of root were achieved when nematode-infested soils were pre- exposed to the T. harzianum preparations. A long-term experiment resulted in improved growth and higher yield of nematode-infected plants, but no significant change in the galling index, either by pre-exposure of the fungus to the soil or by enrichment in the root-ball.As biocontrol is an integral part of the IPM philosophy, judicious use of Trichoderma against soilborne pathogens, when demonstrated to be consistently effective, practical and economic, can serve as a model for the introduction and implementation of other biocontrol means into IPM.  相似文献   
42.
A study was carried out to determine the possibility of a more-closed farming system for (Dutch) dairy farms. The objective of the study was to provide effective and economically profitable management advice for improving the animal-health status of farms. Management measures will only be successfully applied if supported by farmers and their advisors (such as veterinarians). Therefore, the perception of farmers and advisors of the importance of various risk factors for the introduction of diseases to a farm was determined by using bovine herpes virus type 1 (BHV1) as an example.

As part of the study, an evening-long workshop was organized and run thrice. In total, 49 farmers, veterinarians and AI technicians participated in these workshops. The computerized questionnaire technique was based on adaptive conjoint analysis (ACA). ACA has the advantage that participants can work with a large number of risk factors in a relatively short period of time. Another advantage of ACA (compared with standard questionnaires) is that the answers from each participant can be checked with regard to consistency with respect to the importance assigned to them. Data from participants with inconsistent responses can be excluded from further analyses. The results of the ACA interview were compared with the risk factors reported in the literature as being associated with BHV1 status (e.g. purchase of cattle, participation in cattle shows) and with farmers' actual management to prevent the introduction of diseases.

The workshop participants were all operating in the dairy sector and they seemed well aware of the risk of direct animal contacts for the introduction of BHV1. Farmers thought visitors to be more risky than did AI technicians and (especially) veterinarians. Farmers who purchased cattle or participated in cattle shows were of the opinion that the risks of direct animal contacts were more important than did farmers who were not involved in those practices. Farmers whose farms were BHV1-positive (and participated in cattle shows more often) thought the risk of participation smaller than did farmers with BHV1-negative farms.  相似文献   

43.
蚕茧价格变化规律及管理对策   总被引:10,自引:2,他引:8  
李瑞 《蚕业科学》1998,24(2):104-108
对1992年以来我国蚕茧价格和蚕茧供求变化进行分析,研究蚕茧价格的波动规律以及蚕茧均衡价格产生的条件,提出蚕茧价格管理的构想与建议。  相似文献   
44.
作者针对朝阳地区酿酒葡萄主要虫害种类及发生规律进行调查研究,以便有针对性进行防治。调查研究发现,主要虫害种类有短须螨、蓟马和蒙古灰象甲,发生高峰期在早春,所以虫害防治重点在葡萄出土上架时期。  相似文献   
45.
对城区绿化植物病虫害防治策略进行了定位,并提出全程防治的8条措施。  相似文献   
46.
In Israel, alternaria black spot (ABS) disease, caused by Alternaria alternata, is the main postharvest factor that reduces quality and impairs storability of persimmon fruit Diospyros kaki cv. Triumph. The fungus infects the fruit in the orchard and remains quiescent until harvest, or renews its development just before harvest, following rain or high humidity; it then preferentially colonizes the stem-end of the fruit. Recent findings suggest the importance of ethylene and respiration during early fruit growth as factors influencing maturity, crack development, and occurrence of ABS in the stem end of the fruit. We tested the effects of the growth regulator Superlon, a mixture of gibberellin (GA4+7) and benzyl adenine (BA), applied at 40 μg mL−1 once a month during three consecutive months, on fruit physiological responses during growth and on ABS occurrence during storage at 0 °C. Superlon treatments during the early stages of fruit growth, i.e., starting 40 days after fruit set (daf), applied once monthly during three consecutive months, inhibited ethylene and CO2 production in the stem end. Treatments applied starting 100 daf enhanced cell proliferation under the fruit cuticle. Regardless of application timing, Superlon delayed chlorophyll degradation, and reduced fruit cuticle cracking and ABS susceptibility during the late stages of fruit growth and during storage. Present results suggest that the phytohormone, acting as a modulator of host physiological responses that result in delayed fruit maturation, is a main factor in enhanced resistance to ABS at harvest and during storage.  相似文献   
47.

Background

Although the pupal parasitoid Trichopria drosophilae is used in conservative and augmentative biocontrol of Drosophila suzukii infestations, current pest management strategies mostly rely on multiple insecticide applications. In this context, the aim of the study was to investigate the baseline toxicity of nine insecticides on D. suzukii larvae and their multiple sublethal effects (LC10) on immature stages of the pest feeding on contaminated diet and T. drosophilae developing within the intoxicated host.

Results

Chlorpyriphos and azadirachtin showed the lowest and the highest LC10, the values of which were 9.78 × 1013 and 1.46 × 103 times lower than their recommended label field rate, respectively. Among tested insecticides, imidacloprid, malathion and dimethoate were the only treatments that did not affect the juvenile development time of D. suzukii, while spinosad and the organophosphates chlorpyriphos and dimethoate did not influence fly pupal size. No sublethal effects were recorded on T. drosophilae degree of infestation (DI) and juvenile development time. On the contrary, cyazypyr and dimethoate negatively affected the success of parasitism (SP) and the number of progeny of the pupal parasitoid, in association with malathion for the first parameter and spinosad for the fertility. Compared to the untreated control, more female progeny emerged following azadirachtin exposure, while dimethoate caused the opposite effect. Imidacloprid, lambda-cyhalothrin and spinetoram decreased hind tibia length of emerged parasitoids.

Conclusion

This study provides new insights on the (eco)toxicological profile of nine insecticides and new information needed to support the deployment of T. drosophilae in the field within the sustainable management techniques against D. suzukii. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.  相似文献   
48.
Agricultural industrialization and the subsequent reliance on pesticides has resulted in numerous unintended consequences, such as impacts upon the environment and by extension human health. Eco‐efficiency is a strategy for sustainably increasing production, while simultaneously decreasing these externalities on ecological systems. Eco‐efficiency is defined as the ratio of production to environmental impacts. It has been widely adopted to improve chemical production, but we investigate the challenges of applying eco‐efficiency to pesticide use. Eco‐efficiency strategies include technological innovation, investment in research and development, improvement of business processes, and accounting for market forces. These components are often part of integrated pest management (IPM) systems that include alternatives to pesticides, but its implementation is often thwarted by commercial realities and technical challenges. We propose the creation and adoption of an eco‐efficiency index for pesticide use so that the broad benefits of eco‐efficient strategies such as IPM can be more readily quantified. We propose an index based upon the ratio of crop yield to a risk quotient (RQ) calculated from pesticide toxicity. Eco‐efficiency is an operational basis for optimizing pest management for sustainability. It naturally favors adoption of IPM and should be considered by regulators, researchers, and practitioners involved in pest management. © 2019 Society of Chemical Industry  相似文献   
49.
在对柑桔主要病虫害综合防治技术系统研究的基础上,以我国北缘桔区特定的生态条件为背景,结合现有的生产水平,组建了我国北缘桔区柑桔主要病虫害综合治理技术体系.该体系由关键性技术、信息、决策、推广和评价反馈5大系统组成;并概述了该体系建立的原理和指导思想.在汉中市、南郑县、勉县的5年试验示范表明,该技术体系的运转实施,经济、社会和生态效益显著提高.  相似文献   
50.
Biodiversity in urban and suburban environments can be supported through establishment of low maintenance-requiring herbaceous vegetation types. Here, we attempt to provide a perspective on the possibilities and limitations of establishing forb-dominated vegetation to support local biodiversity and contribute to changing public aesthetics concerning green spaces. Plant ecological theories, methods and experiences are the foundation for the design and establishment of such vegetation types. We emphasise the importance of high plant density and recurrent disturbance for the maintenance of forb communities. Well-established ecological theory tells us that totally self-sustaining herbaceous vegetation is not a realistic possibility. Without intervention, herbaceous vegetation will change over time and eventually be colonized by woody species through the process of succession. However, by applying a creative and strategic approach to establishment and subsequent management involving small scale disturbances, rather than solely a uniform maintenance regime, it may be possible to maintain a colourful, aesthetically appealing and species-rich forb dominated community that will support biodiversity and increase public acceptance of alternatives to conventional lawns in urban and suburban environments.  相似文献   
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