共查询到10条相似文献，搜索用时 171 毫秒
1.
种群数量控制指数及其应用 总被引：18，自引：4，他引：18
本文在Morris-Watt种群数学模型的基础上提出种群数量发展趋势的控制指数。控制指数是控制因子对种群生命系统控制作用的指标,以作用于系统内部组分引起的存活率的倒数表示,或以作用后的存活率与原来的存活率的比值表示。控制指数值即为引起种群数量发展趋势发生改变的倍数。文内以稻纵卷叶螟、褐稻虱和三化螟为例,应用控制指数,讨论天敌、杀虫剂和插植期对害虫种群生命系统控制的作用。控制指数有助于研究害虫防治的策略问题。 相似文献
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This review deals with the biology and control of a biting pest species, Simulium posticatum, which has been responsible for a considerable degree of distress to the human population in the vicinity of the River Stour in Dorset. Each phase of the life cycle of the insect is considered in relation to possible control measures. An account is given of how this information has been combined with the use of Bacillus thuringiensis in a successful, precisely targeted attack on the pest. 相似文献
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白翅叶蝉Erythroneura subrufa(Motschulsky)成虫与若虫均以刺吸口器刺进水稻叶片组织内吸取叶汁和叶绿素,被害初期,叶片上出现零星小白点,随后出现长短不一的点状白色斑条,受害严重的稻叶上满布白色斑纹,叶绿素丧失,叶片干萎。在稻叶蝉中除一点小叶蝉被害状出现小白点外,其他叶蝉为害水稻时,并不直接破坏叶绿素,亦不呈现白色斑纹,而是直接吸食叶液,使禾苗发黄而死。因而纠正了过去认为黑尾叶蝉、白翅叶蝉为害水稻后,都会造成叶片出现白色或褐色斑纹的报道。白翅叶蝉在湖南一年发生三代,在晚稻收割后以成虫迁向麦田、杂草等场所越冬,因其寿命很长,故长期不同世代交错。白翅叶蝉除为害水稻外,在初冬与早春还为害冬小麦。近年在湖南及我国南方部分稻区有回升趋势。 相似文献
4.
中国水稻纵卷叶螟防控技术进展 总被引：7，自引：3，他引：4
水稻纵卷叶螟是我国水稻上的重要害虫,近年来给我国水稻生产造成了严重损失。目前,我国水稻纵卷叶螟主要有2种,即稻纵卷叶螟Cnaphalocrocis mendinalis(Guenée)和稻显纹纵卷叶螟Cnaphalocrocis exigua(Butler)。本文分别从生态学特性、测报技术和防控技术等方面对水稻纵卷叶螟的防控技术进展进行了综述。水稻纵卷叶螟的防控要坚持"绿色植保"理念,推行无害化治理;且应在测报数据分析的基础上,充分利用农业与物理防治和生物防治相结合的方法,并配以生态工程技术进行综合治理,以达到减药控害的目的。 相似文献
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The influence of weather on the population dynamics of Oebalus poecilus, the principal insect pest of rice in South and Central America, is examined. Light trapping was used for one year, but was soon discarded in favour of the more reliable sweep netting which was utilised to monitor populations in fields and non-cropped habitats from autumn 1999 to spring 2002. The results indicate that O. poecilus feeds on alternative host grasses on levées surrounding the rice fields. Adult bugs move into the fields in mid-January and mid-August of each year. In fields there are typically four generations per season, which are approximately four weeks apart. Adults move off the crop in April and October. Data presented here indicate that rainfall is critical to the ‘off-season’ survival of O. poecilus, and high rainfall during April to July and November to January causes increases in O. poecilus populations. This is particularly important given the recent extreme perturbations in the normal bimodal rainfall patterns caused by El Niño and La Niña events. The ability to predict the severity of O. poecilus populations from weekly rainfall data will provide a significant input into the development of IPM programme for O. poecilus. 相似文献
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Loganathan Karthiba Kandasamy Saveetha Seetharaman Suresh Thiruvengadam Raguchander Duraisamy Saravanakumar Ramasamy Samiyappan 《Pest management science》2010,66(5):555-564
BACKGROUND: The biological control of plant pests and diseases using a single organism has been reported to give inconsistent and poor performance. To improve the efficacy, bioformulations were developed possessing mixtures of bioagents. RESULTS: Bioformulations combining Pseudomonas fluorescens Migula strains Pf1 and AH1 and Beauveria bassiana (Balsamo) Vuill. isolate B2 were developed and tested for their efficacy against leaffolder pest and sheath blight disease on rice under glasshouse and field conditions. The combination of Pf1, AH1 and B2 effectively reduced the incidence of leaffolder insect and sheath blight disease on rice compared with other treatments. An in vitro assay of leaffolder preference to rice leaf tissues treated with Pf1 + AH1 + B2 biformulation showed variation from normal growth and development of leaffolder larvae. Plants treated with the Pf1 + AH1 + B2 combination showed a greater accumulation of enzymes, lipoxygenase and chitinase activity against leaffolder insect compared with other treatments. Similarly, the plants showed a higher accumulation of defence enzymes, peroxidase and polyphenol oxidase activity against sheath blight pathogen in Pf1 + AH1 + B2 treatment compared with the untreated control. The bioformulation mixture attracted the natural enemy population of leaffolder under field conditions. In addition, a significant increase in rice grain yield was observed in Pf1 + AH1 + B2 treatment compared with the untreated control. CONCLUSION: The combination of P. fluorescens strains and B. bassiana isolate effectively reduced the incidence of leaffolder insect and sheath blight disease on rice plants and showed the possibility of controlling both pest and disease using a single bioformulation. Copyright © 2010 Society of Chemical Industry 相似文献
9.
Biology of Southern rice black‐streaked dwarf virus: a novel fijivirus emerging in East Asia 
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下载免费PDF全文 Southern rice black‐streaked dwarf virus (SRBSDV) was first reported in southern China in 2001 and causes a striking disease on rice and maize that leads to serious yield losses in several East Asian countries, such as China, Vietnam and Japan. A large research effort has been directed to understanding the virus and controlling the disease. Its geographic distribution, disease cycle via its insect vector, genome organization, relationship with host plants, and epidemiology are summarized in this review and the important role played by the vector, the white‐backed planthopper (Sogatella furcifera), is emphasized. Countermeasures to control the disease that have been developed and applied include molecular detection for precise forecasting, chemical, physical, and ecological pest management. There is widespread insecticide resistance in the vector population but it is hoped that current efforts to develop rice cultivars resistant to the virus will eventually provide effective and cost‐effective control. 相似文献
10.
R.W. Caudwell 《Integrated Pest Management Reviews》2000,5(4):297-301
Production and trade in oil crops has expanded in response to an increasing world population and improved living standards. The global production of oil palm has increased rapidly over the last 30 years, and palm oil is now the world's second most important vegetable oil after soybean. Oil palm is an important cash crop in Papua New Guinea (PNG), with about 80,000ha in cultivation, grown both on large-scale plantations and by smallholders. The principal pests of oil palm in PNG are a group of insect species from the Tettigoniidae family (Orthoptera), known collectively as sexava. Three species of sexava are pests of oil palm in PNG, Segestes decoratus, Segestidea defoliaria and Segestidea novaeguineae. These insects cause damage by feeding on oil palm fronds and defoliation levels can be very severe where high populations occur. Severe defoliation causes reductions in photosynthesis resulting in yield loss from lower fruit production. During the last five years an integrated system has been developed for the management of sexava. This integrated pest management (IPM) system has the following components: (1) a knowledge of the biology and ecology of the pest, (2) economic thresholds, (3) monitoring system for the pest, (4) precise targeting of chemical control agents, (5) biological control, and (6) cultural control. The IPM system is sustainable and environmentally acceptable to the industry. 相似文献