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1.
马尾松林节肢动物群落的稳定性   总被引:1,自引:1,他引:0  
依据广西大青山马尾松林区马尾松毛虫一个暴发周期中食叶、捕食、寄生、刺吸四大类群多样性指数(H′)、丰富度指数(MD)、均匀度指数(J)和害虫与天敌的数量比例的数据,建立突变模型对马尾松林节肢动物群落的稳定性进行研究,并利用湖南桂阳数据对模型进行了检验.结果表明:在马尾松毛虫的整个暴发过程中,暴发区在暴发年的昆虫生物群落处于明显的不稳定状态,而在非暴发年时,群落则处于亚稳定的状态;非暴发区在暴发年处于亚稳定的状态,非暴发年时处于稳定状态.在松毛虫各个发生阶段,当上升期处于不稳定状态时,有可能导致松毛虫的大发生;松毛虫暴发后,节肢动物群落依旧处于不稳定状态,有可能会造成松毛虫的连续暴发,这主要依赖于各种因子的影响.马尾松毛虫暴发呈现非线性、突变性等特点,食叶类群的影响为马尾松毛虫暴发的关键因子,各类群作用均衡的系统比较稳定,虫害暴发是群落结构趋稳调节过程中的强烈外部表现.研究表明,突变模型在检测群落结构稳定性和预测松毛虫发生上有很好的应用前景.  相似文献   

2.
松毛虫监测与防治方法研究进展   总被引:21,自引:0,他引:21  
李天生 《昆虫知识》2000,37(2):122-128
松毛虫Dendrolimusspp.是我国分布最广的历史性的松树害虫。我国共有27种松毛虫,其中6种危害较严重,马尾松毛虫列为第一位。松树是我国重要的森林资源,总面积约为3.3-4千万hm2。松树不仅广泛用于民用和工业建材,而且在涵养水源、净化空气等方面有着重大生态效益。随着我国经济迅速增长与人口的增加,天然林面积锐减,人工林面积增大,生态系统遭到破坏,以致松毛虫发生面积逐渐增大。据近年来统计,松毛虫发生面积平均约2.7万hmz。建国以来,在松毛虫生物学、生态学研究以及防治手段与综合管理方面,取得了很大成绩。有关松毛虫种…  相似文献   

3.
我国蝗虫暴发成灾的现状及其持续控制对策   总被引:18,自引:2,他引:16  
概述并分析了我国蝗虫暴发成灾的现状及原因 ,认为全球气候变暖和区域性气候异常、人类活动的影响、监测预警技术手段落后、成灾蝗种增多和发生为害类型复杂、蝗虫研究队伍锐减及基础理论与高新技术研究滞后导致了近年来蝗虫的暴发成灾。对此 ,作者从蝗虫灾害的规律性、监测预警高新技术和综合治理技术等方面提出了实现蝗灾可持续控制的对策  相似文献   

4.
赵同海  陈昌洁 《昆虫知识》2004,41(3):212-216
综述了松毛虫CPV不同分离株基因组电泳图谱的研究状况。松毛虫CPV是松毛虫Dedrolimusspp .的重要病原微生物 ,在松毛虫灾害治理中起着重要作用。病毒基因组电泳图谱是CPV重要的分类依据和研究基础。到目前为止 ,全世界范围共分离报道了 1 0株不同的松毛虫CPV ,基因组电泳图谱研究表明CPV -1型是松毛虫CPV的主要类型。PAGE分析显示 ,松毛虫CPV不同分离株中至少存在有 3种不同CPV -1的型内变异 ,它们有时以纯一型或混合型的形式出现。特别需要指出的是中国马尾松毛虫CPV分离株 ,其存在有 2种不同形态的病毒多角体 ,通过蔗糖密度梯度离心可以分为上下 2条带 ,上带多角体为锥形 ,基因组dsRNA电泳图谱显示 1 3条带 ,不属于目前已确定的 1 4种电泳型中的任何一种 ;下带多角体为六边形 ,基因组为纯合的CPV -1型 ;另外在不同时期不同地方感染马尾松毛虫也分离得到了纯合型的马尾松毛虫CPV -型  相似文献   

5.
何忠  韩瑞东  黄丽莉  戈峰 《昆虫知识》2006,43(4):486-491
研究不同受害程度松林与马尾松毛虫Dedrolimuspunctatus(Walker)种群发育阶段的关系。结果表明,松毛虫大面积发生时松林的受害程度可以很好地标示着松毛虫种群的发生阶段。松林点片受害显示松毛虫种群进入上升开始阶段;松林受害程度中等时,松毛虫仍处于上升种群阶段;当松林的针叶被吃光,表明松毛虫已处暴发阶段。松毛虫暴发种群在自然情况下,将出现典型的蛹期和下一代卵期的寄生率大幅度升高、雌性比、蛹重和产卵量等种群参数大幅度下降等特征;其后代会自然转入下降种群或进入低虫口期。但这些暴发种群的卵转入在保证充足饲料的可控条件下饲养时,其后代的生长发育、存活率、性比、蛹重等主要种群参数没有明显差异。即没显示出上升种群和暴发种群的特征差异,说明暴发种群的终止主要是受外界环境的限制而不是松毛虫本身的内因所致。  相似文献   

6.
影响松毛虫种群动态的因素   总被引:3,自引:0,他引:3  
韩瑞东  何忠  戈峰 《昆虫知识》2004,41(6):504-511
综述了影响松毛虫种群动态的因素。气候、天敌、食料、林业技术措施等都不同程度地影响着松毛虫种群的变动。当气候条件适宜 ,天敌数量减少 ,食料丰富 ,林业技术措施缺乏时 ,松毛虫种群就会出现暴发的趋势。反之 ,当气候条件恶劣、天敌数量较多 ,食料植物缺乏或营养恶化 ,林业技术措施得当时 ,松毛虫种群就会得到遏制。尽管松毛虫的种群变动受到多种因素影响 ,但是对松毛虫自身调节能力的研究尚缺乏。  相似文献   

7.
落叶松毛虫是大兴安岭林区的主要食叶害虫之一,利用模型模拟其景观尺度的空间分布、揭示其发生机理对落叶松毛虫灾害的预防和治理具有重要意义。本研究基于黑龙江省大兴安岭林区下辖3个林业局2008—2012年落叶松毛虫发生数据(小班水平),应用广义线性模型和最大熵模型预测了落叶松毛虫在立地条件、林分结构等环境变量共同作用下的空间分布,对比分析了环境变量的相对重要性,量化了落叶松毛虫发生概率对环境变量的响应规律。结果表明:广义线性模型与最大熵模型均取得了较好的预测结果,两种模型预测落叶松毛虫发生概率的空间分布大体一致,但通过设定不同的虫害发生概率阈值,适宜发生面积存在明显差别。海拔、龄组、土壤厚度、落叶松百分比是影响落叶松毛虫分布的重要环境变量。其中,落叶松毛虫发生概率在海拔300 m附近最高;中龄林、幼龄林的发生概率显著高于其他龄组;土壤厚度薄的小班更易爆发成灾;虫害发生概率与落叶松比例存在非线性正相关关系。  相似文献   

8.
我国农业害虫综合防治研究进展   总被引:5,自引:0,他引:5  
农业害虫综合防治是昆虫学的一门应用科学,旨在明确农作物害虫的发生危害与暴发成灾规律,提出害虫监测预警和可持续治理的理论与方法。在2012-2016年的5年间,我国提出了基于生态系统服务和多尺度空间管理的害虫生态调控新理论,发展了害虫行为调控技术和化学防治新技术,并在棉铃虫对Bt棉花抗性治理对策、稻飞虱的监测预警和综合防控技术、小菜蛾抗药性诊断及治理技术、青藏高原农牧害虫发生规律和分区治理等防治实践中取得了重要进展。根据国际上害虫综合防治学科发展趋势和我国的研究现状,将来还需要在害虫灾变机制研究、害虫绿色防控技术创新研发以及集成应用等方面进行深入探索,为我国农业害虫可持续治理以及化学农药减量使用提供有力的科技支撑。  相似文献   

9.
我国马尾松毛虫寄生性天敌的研究进展   总被引:1,自引:0,他引:1  
马尾松毛虫Dendrolimus punctatus(Walker)的寄生性天敌主要包括寄生蜂和寄生蝇类两大类。文章列出我国马尾松毛虫主要寄生蜂58种和寄生蝇类20种的名录与寄生的虫态,着重综述了松毛虫赤眼蜂Trichogramma dendrolimiMatsumura、松毛虫黑卵蜂Telenomus dendrolumusiChu、白跗平腹小蜂Anastatus albitarsis(Ashmead)、黑足凹眼姬蜂Casinaria nigripes(Gravenhorst)、松毛虫脊茧蜂Aleiodes dendrolimi(Matsumura)等5种优势种寄生蜂的研究和应用进展,同时还介绍马尾松毛虫寄蝇在野外寄生状况、室内饲养繁殖等方面的研究概况,以期为马尾松毛虫寄生性天敌的进一步研究提供借鉴。  相似文献   

10.
不同松林内马尾松毛虫种群动态的特征   总被引:6,自引:0,他引:6  
通过对1992-2001年5种不同混交林型的马尾松林内各代幼虫发生量,受害面积和有虫株率的系统调查,研究了各种不同林型的松林对马尾松毛虫种群动态的影响。结果表明,不同树种混交的马尾松林对马尾松毛虫的种群动态有较大的影响。马尾松毛虫在马尾松纯林中发生量多,为害最严重。暴发周期最短;在与杉木等混交的马尾松林中发生次之;而在与阔叶树混交的马尾松林中平均每株虫口数少,发生与危害率及有虫株率均较其它林型小,不易引起松毛虫暴发为害。  相似文献   

11.
松毛虫质型多角体病毒的宿主域与交叉感染   总被引:2,自引:0,他引:2  
自1956年从赤松毛虫Dendrolimus spectabilis上首次发现赤松毛虫质型多角体病毒1型(D. spectabilis cytovirus 1,DsCPV-1)以来,先后从马尾松毛虫D. punctatus、油松毛虫D. tabulaeformis、赤松毛虫、德昌松毛虫D. p. tehchangensis、文山松毛虫D. p. Wenshangensis和落叶松毛虫D. superans上发现了质型多角体病毒(cytoplasmic polyhedrosis virus,CPV)。病毒基因组dsRNA电泳图谱分析表明,这些松毛虫CPV的不同分离株均属于质型多角体病毒1型(cytovirus 1)。这些松毛虫CPV病毒可以感染鳞翅目10科35种昆虫,其中对多种昆虫具有很高的感染力和良好的杀虫效果,可以从中筛选替代宿主生产松毛虫CPV杀虫剂,用于害虫生物防治。松毛虫CPV接种某些昆虫后病毒的基因组dsRNA电泳图谱发生了改变,可能是异源病毒诱发了宿主自身潜伏型病毒的感染复制。  相似文献   

12.
The pest termites of South America: taxonomy, distribution and status   总被引:3,自引:0,他引:3  
Abstract: A total of 77 species of termites have been reported as structural or agricultural pests in South America. These records are reviewed, with indication of the damage they cause, their pest status, distribution and sources of information. Among these, 40 species are reported as structural pests, 53 species as agricultural pests and 15 species as both. However, only 18 species are considered major pests and the status of most of the others is uncertain. Uncertainty about status is much higher among agricultural pests. Specific taxonomic problems are discussed and distribution maps of the main pest genera and species are presented. The most important structural pests are the introduced Coptotermes havilandi and Cryptotermes brevis and the native Nasutitermes corniger. Reticulitermes was introduced into Uruguay and Chile, where it is the only serious pest. The main agricultural pests are Heterotermes spp., Nasutitermes spp., Cornitermes spp., Procornitermes spp. and Syntermes spp., and the most affected crops are sugarcane, upland rice and eucalyptus.  相似文献   

13.
In Japan, several forest-defoliating insects reach outbreak levels and cause serious defoliation. Stand mortality sometimes occurs after severe defoliation. However, in general, tree mortality caused by insect defoliation is low because of the prevailing moist climate in Japan. Evergreen conifers are more susceptible to tree mortality as a result of insect defoliation whereas deciduous broad-leaved trees are seldom killed. Insect defoliation occurs more frequently in man-made environments such as among shade trees, orchards, and plantations than in natural habitats. Outbreaks of some defoliators tend to occur in stands of a particular age: e.g. outbreaks of the pine caterpillar, Dendrolimus spectabilis Butler (Lepidoptera: Lasiocampidae) occur more frequently in young pine plantations. In contrast, defoliation caused by outbreaks of lepidopterous and hymenopterous pests in larch plantations is more frequent with stand maturation. There is a relationship between outbreaks of some defoliators and altitude above sea level. Most outbreaks of forest defoliators were terminated by insect pathogens that operated in a density-dependent fashion. Since the 1970s, Japan has been prosperous and can afford to buy timber from abroad. More recently, there has been an increasing demand for timber in Japan, that coincides with a huge demand internationally, so that the country will need to produce more timber locally in the future. The increasing pressure on the forestry industry to meet this demand will require more sophisticated methods of pest control coupled with more sustainable methods of silviculture.  相似文献   

14.
Examination of more than 500 herbarium specimens of Eucalyptus marginata and E. rudis for the presence of two species of leafminers, Perthida spp., indicated that these native insect species were very rare in southwest Western Australia until first recorded in metropolitan Perth in 1878 and 1897, respectively, when west coast populations of both leafminer species evidently increased dramatically. The first record from the south coast dates from 1901 near Albany. Evidence of leafminer populations on E. marginata remote from coastal settlements was not recorded until 1917, near Cranbrook. The first record in jarrah forest was in 1967, some 10 years after outbreaks of the pest insect are known to have occurred in the forest. The Perthida leafminer species on E. rudis was first recorded from inland areas in 1904 and appears to have increased more rapidly in abundance than the species found on E. marginata. These early geographical and species differences in incidence are discussed in terms of changing disturbance patterns, which have not been simultaneous across southwest Western Australia.  相似文献   

15.
《新西兰生态学杂志》2011,30(1):150-151
[First paragraph]Improved grasslands pose particular problems in pest management. The areas are extensive and the returns per hectare from grassland agriculture are much less than those from intensive cropping or horticulture, but pastures are usually sown to last for a number of years and have a much more stable ecology than in cropping or horticulture. For these reasons, biological controls and plant resistance have long been the preferred options for managing pasture pests. Within this context, the role of diseases in pasture pest population dynamics has received increasing attention, especially their ability to control pest outbreaks. Diseases are common within our major pasture pest species but their role in population regulation is often difficult to define. One of New Zealand’s major pasture pest species, the grass grub Costelytra zealandica, is widespread and often damaging throughout the country. The insect is an endemic species that has adapted to an introduced pasture system, dominated by exotic plant species (Lolium perene/Trifolium repens), where it can reach populations ten-fold higher than in its native habitat. Such high densities favour disease transmission and it is not surprising that a wide array of pathogens have been recorded from this insect (Glare et al., 1993). But the insect can still be highly damaging and can cause total loss of sown species within 3–4 years from sowing in grass grub prone regions. Probably the most important of these diseases, found throughout New Zealand, is amber disease caused by strains of the bacteria Serratia entomophila and S. proteamaculans. This is an unusual disease, controlled by a bacterial plasmid which has only been found in New Zealand bacterial isolates (Jackson et al., 2001).  相似文献   

16.
The growth of the Brazilian forest sector with monocultures favors the adaptation of Arthropoda pests. The Lepidoptera order includes major pests of Eucalyptus spp. (Myrtaceae). The aim of this work is to study the population constancy, distribution, and frequency of Lepidoptera primary pests of Eucalyptus spp. Lepidoptera pests in Eucalyptus spp. plantations were collected in Três Marias and Guanhães (state of Minas Gerais), Niquelândia (state of Goiás), and Monte Dourado (state of Pará), Brazil, for a period of 5 years, with light traps and captures, every 15 days, for every region. The number of primary pest species (12) has been similar in the four regions, and even with 1.5 to 2.4% of the total species collected, this group has shown a high frequency, especially in Três Marias, Niquelândia, and Monte Dourado, with 66.3, 54.2, and 40.0% of the individuals collected, respectively, for 5 years. The primary pest species have been constant and frequent in all the regions, with population peaks from February to September in Três Marias, February and May in Niquelândia, and from July to September in Monte Dourado. The highest population peaks of these species have been recorded when the Eucalyptus spp. plants are 3 to 6 years old. The Guanhães region is more stable and, therefore, has a lower possibility of outbreaks of the Lepidoptera primary pest species.  相似文献   

17.
1. Range expansions mediated by recent climate warming have been documented for many insect species, including some important forest pests. However, whether climate change also influences the eruptive dynamics of forest pest insects, and hence the ecological and economical consequences of outbreaks, is largely unresolved. 2. Using historical outbreak records covering more than a century, we document recent outbreak range expansions of two species of cyclic geometrid moth, Operophtera brumata Bkh. (winter moth) and Epirrita autumnata L. (autumnal moth), in subarctic birch forest of northern Fennoscandia. The two species differ with respect to cold tolerance, and show strikingly different patterns in their recent outbreak range expansion. 3. We show that, during the past 15-20 years, the less cold-tolerant species O. brumata has experienced a pronounced north-eastern expansion into areas previously dominated by E. autumnata outbreaks. Epirrita autumnata, on the other hand, has expanded the region in which it exhibits regular outbreaks into the coldest, most continental areas. Our findings support the suggestion that recent climate warming in the region is the most parsimonious explanation for the observed patterns. 4. The presence of O. brumata outbreaks in regions previously affected solely by E. autumnata outbreaks is likely to increase the effective duration of local outbreaks, and hence have profound implications for the subarctic birch forest ecosystem.  相似文献   

18.
Aspects of predator assemblages that alter predator effects on prey have received extensive recent attention. Among other mechanisms, differences in behavior or resource use within predator trophic levels may enhance predator effects on prey, especially if effects of each predator species differ with environmental conditions. We address whether three common ant species (Azteca instabilis F. Smith, Camponotus textor Forel, and Crematogaster spp.) are functionally unique in coffee agroecosystems, asking if each species differs in (1) cooperative foraging behavior, (2) responses to experimentally introduced herbivores, and (3) responses to pest outbreaks. Furthermore, we examined the behaviors and effects of each ant species under different conditions by varying herbivore species, herbivore size, and herbivore density and carrying out observations in different seasons. Ant species significantly differed in foraging behaviors, in effects on individual herbivores, and in responses to pest outbreaks in terms of both type and time of response to herbivores. The behaviors and effects of each ant species differed in the dry and wet seasons and for different herbivore species and sizes. Although A. instabilis generally removed more larvae and more quickly removed larvae, this was not the case under all conditions. The data presented thus support that common ant species in coffee agroecosystems are behaviorally diverse in their responses to herbivores under different conditions. We discuss the implications of these differences in ant behaviors for enhancement of predatory function in light of both multipredator effects and in terms of the potential importance of predator diversity.  相似文献   

19.
花曲柳窄吉丁的寄主植物范围、危害和防治对策   总被引:5,自引:2,他引:3  
花曲柳窄吉丁(emerald ash borer, EAB) Agrilus planipennis Fairmaire是木犀科(Oleaceae)梣属Fraxinus植物树木的毁灭性蛀干害虫,目前发现其主要危害欧梣亚属Subgen. Fraxinus欧梣组(Section Fraxinus)和象蜡树组(Section Meliodes)的一些树木种类,如美国白蜡Fraxinus americana、洋白蜡F. pennsylvanica var subintegerrima、绒毛白蜡F. velutina、黑白蜡F. nigra和水曲柳F. mandshurica等。与早期文献上的记载不同,很少发现花曲柳窄吉丁对苦枥木亚属Subgen. Ornus白蜡树组(Section Ornaster)的白蜡树F. chinensis Roxb和花曲柳F. rhynchophylla造成危害。不同寄主白蜡树对花曲柳窄吉丁的敏感性不同,洋白蜡、绒毛白蜡等北美白蜡树种受其危害重于亚洲的水曲柳。这可能是由于长期的适应进化,分布在亚洲地区的梣属寄主树木发展了对花曲柳窄吉丁的抗虫性。中国部分地区发生的花曲柳窄吉丁灾害应该归属于引进的北美白蜡树种对本地害虫敏感所致。在天津、黑龙江、吉林、辽宁、河北、山东、四川、台湾、内蒙古和新疆等省市和自治区,都曾发现花曲柳窄吉丁的危害或分布。白蜡属树木广泛分布于我国除了青藏地区和海南省之外的大部分地区,其中大面积引种北美白蜡树种的北方和西北地区,以及近年来种植发展水曲柳的东北地区都是花曲柳窄吉丁这种毁灭性蛀干害虫的潜在发生地。花曲柳窄吉丁在我国部分地区为检疫性林业害虫,做好检疫是杜绝其扩散蔓延的首要方法。我国局部地区出现花曲柳窄吉丁灾害说明,北美白蜡树种在我国的适应性还需要进行更进一步科学的全面的风险评估,在我国生态建设中应重视利用我国本地的白蜡树种。在花曲柳窄吉丁灾害的治理中,可采用营造混交林以降低蔓延的速度和发挥自然控制能力,加强肥水管理以增强树木的抗虫能力,清除被害木消灭虫源,以及幼虫期树干注射、成虫期喷洒化学农药等防治措施。  相似文献   

20.
ABSTRACT

Wild mammalian herbivores can compete with domestic livestock and damage other types of production systems. We reviewed damage by wild mammalian herbivores, excluding rodents, to primary production in New Zealand and assessed whether primary producers alter stocking rates in response to changes in forage availability following pest control. Given the dearth of information on the damage caused by wild mammalian herbivores to many production systems, we primarily focused on their damage to agriculture. With the exception of the substantial damage that brushtail possums (Trichosurus vulpecula) and European rabbits (Oryctolagus cuniculus) cause, there are no quantitative estimates of pasture depletion by other wild mammalian herbivores on New Zealand farmland. Estimates of dry matter consumption by wild mammalian herbivores, converted to stock unit equivalents, suggest that several species can substantially reduce stocking rates when they occur on farmland. Quantitative data on the damage they cause to horticulture and silviculture are lacking, but damage to coniferous seedlings has been recorded for possums, wallabies (Notamacropus spp.), and some species of deer (Cervus spp., Rusa spp., and Dama dama). The process that primary producers use to decide whether to control wild mammalian herbivores includes complex social and economic factors, but quantitative information is important for weighing up the expected costs and benefits of pest control. However, it is unclear how primary producers manage livestock in response to increases in forage availability following pest control. The paucity of quantitative data on wild mammalian herbivore damage to production assets is a substantial knowledge gap. Key research priorities are (i) understanding how damage varies with pest density (critical information for effective pest management) and (ii) and how primary producers alter stocking rates following reductions in pest density.  相似文献   

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