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1.
绿僵菌药后草原蝗虫种群空间分布型研究   总被引:4,自引:0,他引:4  
综合多个聚集度指标对绿僵菌药后田间蝗虫和僵虫的空间分布型进行了研究。结果表明:施药后不同时间随蝗虫种群密度的减小,处理区残虫的分布型呈现聚集随机交错变动,僵虫的空间分布型为聚集分布。采用Taylor幂法则和改进的Iwao模型分析表明,整个调查时段处理区残虫、僵虫的空间分布均为聚集分布。推测认为,药后蝗虫点片状死亡,部分地片相对密度较高,残虫分布型趋向聚集; 自然消除作用使僵虫密度很低,低密度下取样产生大量空样本,僵虫的分布型产生聚集假象。  相似文献   

2.
烟盲蝽及其天敌蜘蛛空间格局的地统计学分析   总被引:6,自引:0,他引:6  
利用地统计学的方法研究了烟草(品种为中烟100)不同生长期烟盲蝽及天敌蜘蛛的空间格局,结果表明:烟盲蝽的空间格局随时间的变化呈现为随机、聚集、再随机和再聚集;尽管蜘蛛混合种群的空间格局也依次表现为随机、聚集、随机和聚集分布,但只是在后期与烟盲蝽的空间格局一致。利用BlockKriging进行空间插值分析,得到的三维空间插值模拟图能很好地反映烟盲蝽和蜘蛛种群的田间分布状况。同时,对烟盲蝽及天敌蜘蛛的种群动态进行了分析,发现它们的种群数量变化趋势相似。所有结果表明蜘蛛种群在较大程度上与烟盲蝽种群存在跟随关系。  相似文献   

3.
棉田绿盲蝽的空间分布型及其抽样模型   总被引:2,自引:0,他引:2  
2009—2010年于河北省廊坊市对棉田绿盲蝽Apolygus lucorum(Meyer-Dür)的空间分布型及其抽样模型进行了研究。结果表明,绿盲蝽成虫空间分布型与其种群密度有关,当种群密度大于百株1.6头时呈随机分布,当小于百株1.6头时一般呈聚集分布;绿盲蝽若虫在不同种群密度下均呈聚集分布;绿盲蝽整个种群呈Possion分布。应用Iwao的抽样模型建立了棉田绿盲蝽的理论抽样数公式:N=(1.35/x珋)/D2。  相似文献   

4.
2009-2010年于河北省廊坊市对棉田绿盲蝽Apolygus lucorum(Meyer-Dür)的空间分布型及其抽样模型进行了研究.结果表明,绿盲蝽成虫空间分布型与其种群密度有关,当种群密度大于百株1.6头时呈随机分布,当小于百株1.6头时一般呈聚集分布;绿盲蝽若虫在不同种群密度下均呈聚集分布;绿盲蝽整个种群呈Possion分布.应用Iwao的抽样模型建立了棉田绿盲蝽的理论抽样数公式:N=(1.35/-(x))/D2.  相似文献   

5.
棉田十一星瓢虫种群动态及空间分布   总被引:1,自引:0,他引:1  
通过田间系统调查,对棉田十一星瓢虫CoccinellaundecimpanctataL.种群动态及空间分布方面进行研究,探明捕食性天敌十一星瓢虫各虫态在南疆棉区的种群消长趋势,分析表明该虫4种虫态在棉田中均为聚集分布,成虫、幼虫和蛹的聚集原因主要是由棉蚜密度等引起,而其卵的聚集主要是由于其习性及环境因素引起。  相似文献   

6.
烟草潜叶蛾幼虫空间分布型及其应用研究   总被引:3,自引:0,他引:3  
本文就烟草潜叶蛾幼虫空间分布型及其垂直分布规律进行了探讨,结果表明:烟草潜叶蛾幼虫在田间呈聚集分布,聚集强度不因种群密度的改变而改变,幼虫主要聚集分布在烟草下部第一段(4片叶)上;降集或随机分布在第二段上;随机分布在第三段上,此外,应用虫株率进行田间种群密度的估计,其中Wilson模型和Gerrard模型所配理论曲线的预测值与实测值显著适合,但Gerrard模型的抽样估计误差较Wilson模型的小,最后本文用Taylor式中的参数a,b确定理论抽样数及序贯抽样,其模型分别为。  相似文献   

7.
黑河上游高寒退化草地狼毒种群小尺度点格局分析   总被引:7,自引:1,他引:6       下载免费PDF全文
植被斑块化是自然界的一种普遍现象, 斑块的形成和变化对植物种群格局的形成和变化具有重要影响。在黑河上游祁连山北坡高寒退化草地, 采用点格局分析方法, 研究了小尺度上狼毒(Stellera chamaejasme)种群的种群密度、组成格局以及分布格局。结果表明: 随着狼毒种群分盖度的增大, 种群密度、领地密度和组成格局呈现规律性的变化, 斑块内部狼毒种群的数量出现增减交替变化趋势, 组成格局规律明显; 狼毒种群的分布格局表现出与尺度关联的变化趋势, 在31%-40%分盖度下, 狼毒种群在所有尺度上表现为随机分布, 在41%-50%、51%-60%、61%-70%、71%-80%分盖度下随着尺度增大, 分布格局的基本模式为: 随机—聚集—随机或均匀—随机—聚集—随机分布, 在聚集状态下, 聚集强度不同。以成株为核心的斑块内部种群表现为随机分布或均匀分布, 相对于外部表现为聚集分布, 随着成株个体数量的逐渐增多, 种群竞争关系由种间竞争转化为种内竞争, 促进了斑块扩张与合并、斑块增多与吞并, 从而实现了种群扩散。  相似文献   

8.
《环境昆虫学报》2013,35(5):560-571
2012年在河北廊坊通过调查作物围种和作物间作两种不同种植模式棉田中烟粉虱Bemisia tabaci(Gennnadius)MED隐种的分布情况得知,烟粉虱在棉花植株上的垂直分布型为聚集分布,上部和中部叶具有比下部叶较多的烟粉虱种群密度。烟粉虱在棉田中的水平分布情况为:未成熟虫期种群在样地中央和样地边缘种群密度无显著差异,在整个发生期属均匀分布;成虫种群在主要发生期围种模式棉田中样地中央的种群密度显著高于样地边缘的种群密度,属于聚集分布,主要分布于样地中央,在整个发生期种群也主要聚集于样地中央分布;而间作模式棉田样地中央和样地边缘的种群密度无显著差异属于均匀分布。说明围种模式在增加了样地边缘的植物物种多样性对烟粉虱成虫的水平分布有较大影响,通过改变种植模式能显著影响烟粉虱成虫在棉田的分布。  相似文献   

9.
淡黄虻是松嫩平原虻虫中的优势种.对其吸血活动的观测发现,其种群数量与温度、湿度呈显著相关;吸血高峰时间出现在14:00左右,种群的聚集度和扩散度也在此时达到最大;种群不仅呈聚集分布,而且呈聚集型扩散;种群聚集分布以疏松的小集团形式存在,其个体呈随机分布.  相似文献   

10.
麦蚜空间格局参数特征及其应用   总被引:4,自引:0,他引:4  
张德昌  齐孟文 《昆虫知识》1993,30(5):267-270
为了进一步了解麦蚜的生物学特性,1986~1991对麦蚜在麦田中的空间格局进行了研究,结果表明麦蚜在麦田中的分布属聚集分布,格局的结构是以疏松的个体群形式存在,个体群间是聚集的,个体群内的个体是随机的,提出了依x=4.2481(-lnp_0)~1.1978关系由无虫株率来估计种群密度,给出了以无虫株率来检定田间发生程度的序贯抽样表。  相似文献   

11.
Abstract: Biology of Hippodamia variegata Goeze (Col., Coccinellidae) and its suitability against Aphis gossypii Glov (Hom., Aphididae) on cucumber under greenhouse conditions. Research work carried out in the laboratory has shown that temperature has a great effect on the development and the amount of feeding of Hippodamia variegata . The optimum temperature for its development and voracity approaches 26°C and the threshold development temperature is about 11.22°C. Investigations on its use in cucumber greenhouses against Aphis gossypii , the release of larvae and adult forms had shown satisfactory results. The efficiency level of this ladybird is a function of the ratio predator/prey and on the level of the aphid population at the moment of the ladybird release. The effect of density of the prey on the fecundity and the settlement of this ladybird under greenhouse conditions were also studied. The biological features and the efficiency of this ladybird are discussed.  相似文献   

12.
In many bark beetles (Coleoptera: Curculionidae: Scolytinae), intraspecific competition is a limiting factor governing their population dynamics. The aim of this study was to evaluate the effect of increasing infestation densities on the breeding performance of Tomicus destruens (Wollaston), one of the main pests of Mediterranean pine forests. Six densities (ranging from 0.25 to 1.50 females   dm−2) were tested under laboratory conditions on stone pine logs, assessing the mortality of eggs, larvae, and pupae, and recording the number of emerging adults. Density significantly affected the fertile tract of the maternal galleries, i.e., those containing eggs, which was shorter at densities higher than 0.75. Numbers of eggs, larvae, pupae, and adults per female decreased markedly when density increased from 0.25 to 1.5, although differences were statistically significant only at a density of 0.75 and higher. The lowest mortality was found in larvae reared at a density of 0.25 (17.7%) and the highest in pupae at 1.5 (84.8%). Increasing density affected the pre-emergence stages in different ways, with pupae and larvae suffering the highest increases in mortality (39.5 and 163.6%, respectively). The breeding performance of T. destruens (number of eggs laid reaching adulthood) progressively decreased from 17 to 4% with increasing densities, although at low infestation, the mean number of emerging adults per dm2 of bark increased with density, showing a positive trade-off between female fecundity and female density. In conclusion, breeding densities higher than 0.75 female dm−2 decreased female fecundity and elicited high mortality, mainly in larvae.  相似文献   

13.
SUMMARY. Certain larvae and pupae have been identified as Notidobia ciliaris (Linné) by rearing field-collected larvae to the adult stage and by rearing larvae from eggs laid by a female in captivity. The larvae differ in many important respects from larvae of this species described by earlier workers. Characters are provided to distinguish these larvae and their associated pupae from those of Sericostoma personatum (Spence). The habitat and distribution of both species in Britain is outlined.  相似文献   

14.
李建庆  梅增霞  杨忠岐 《生态学报》2016,36(14):4540-4547
云斑白条天牛是我国重要林业害虫,在黄河三角洲地区对白蜡树造成严重危害。利用地统计学方法,通过调查城市行道绿化林、庭院绿化林、公路林和片林4种不同林分类型的白蜡树林地,以产卵刻槽、排粪孔和羽化孔为调查指标,对危害白蜡云斑白条天牛种群卵、幼虫、成虫(蛹)的空间格局进行了研究。结果表明:除片林样点成虫(蛹)的半变异函数模型为指数模型外,危害白蜡云斑白条天牛种群卵、幼虫、成虫(蛹)在不同林分类型下的半变异函数模型均为球形模型,其指明空间分布均为聚集分布,种群的聚集分布习性与林分类型相关性不强。但不同林分类型云斑白条天牛种群的空间相关性地统计学参数存在差异,片林调查样点的卵、幼虫和成虫(蛹)的变程a、块金值C0和基台值C0+C均小于其他3种林分类型的统计值,片林样点成虫(蛹)的半变异函数模型不同于其他林分类型为指数模型。  相似文献   

15.
Spatial distribution of immatures of the banana skipper (Erionota thrax L.) and their parasitisms from three major parasitoids were studied in a Cavendish banana plantation from April 2004 to December 2004. Infestation levels and parasitism of E. thrax life stages were recorded from bunched plants (BP), flowering plants (FP), preflowered plants (PF), broad leaf followers (BLF) and narrow leaf followers (NLF), as well as on well managed and poorly managed plants. Mean numbers of the immatures and numbers parasitized from the nine blocks in the plantation were fitted to four dispersion indices. Significant numbers of E. thrax immatures and those parasitized by Ooencyrtus erionotae, Cotesia erionotae and Brachymeria albotibialis were recorded from BLF and PF; no eggs were found on BP and FP. Although infestation was higher on well managed plants, only larval parasitism was significantly different. Three of the four indices indicated that eggs and larvae were random while all the indices showed pupae to be clumped. Parasitized eggs and pupae were clumped (4/4 indices) while 3/4 indices revealed a random pattern for parasitized larvae.  相似文献   

16.
Intraguild predation (IGP) is an interaction that frequently occurs in natural enemy communities, especially aphidophagous predators. This research investigated IGP intensity between Episyrphus balteatus De Geer (Diptera: Syrphidae), with Hippodamia variegata Goeze (Coleoptera: Coccinellidae). Five predator combinations including second and third larvae of H. variegata and third instar larvae of E. balteatus plus control treatment (totally six treatments) were tested. The effect of IGP on cotton aphid, Aphis gossypii Glover (Hemiptera: Aphididae) population density was investigated on sweet pepper seedlings under laboratory microcosms. In most combinations, the third instar larvae of E. balteatus alone reduced an A. gossypii population more efficiently than ladybird larvae and their combinations. Furthermore, IGP between third instar of E. balteatus and second larvae of H. variegata was asymmetrical; second instar H. variegata larvae were always the intraguild prey for third instar E. balteatus. The obtained result showed that outcome of IGP interaction on cotton aphid density was non-additive.  相似文献   

17.
幼虫密度对二点委夜蛾生长发育及繁殖的影响   总被引:1,自引:0,他引:1  
【目的】在不同幼虫密度饲养条件下,研究二点委夜蛾Athetis lepigone生长发育及繁殖的情况,明确幼虫密度对该害虫的室内种群增长的影响。【方法】本实验设置5个幼虫饲养密度即1,5,10,20和30头/瓶(750 mL),分别观察5个饲养密度下该虫的各个龄期及整个幼虫发育历期及存活率、蛹重、蛹期以及成虫生殖情况。【结果】幼虫密度对该虫幼虫各龄期及整个幼虫发育历期及存活率、蛹重、蛹期以及成虫生殖情况均有显著性影响。整个幼虫发育历期随着密度的增加而缩短,10头/瓶达到最短(18.27 d),之后随着幼虫密度的增加而显著延长;幼虫至蛹的存活率随着密度增高而显著下降,30头/瓶最低(39.37%)。蛹期随着密度的增加而延长(10头/瓶除外)。蛹重和每雌产卵量均以1头/瓶最高,随着幼虫密度的增加而显著下降。雌雄蛾寿命均以10头/瓶最长,与1和5头/瓶没有显著性差异。生命表分析显示:二点委夜蛾的种群增长指数以5头/瓶最高,幼虫密度过低或者过高均不利于种群增长。【结论】幼虫密度是影响二点委夜蛾种群增长的重要因子之一。  相似文献   

18.
We investigated the effect that different categories of brood had on the production of periodic activity within artificial aggregates of the ant,Leptothorax allardycei. Colonies of this species exhibit periodic patterns of movement activity with a period of approximately 20–30 min. Artificial aggregates of this species show that periodic activity appears gradually as the number of workers in the aggregate increases to 15 workers. In addition, it has been noted that the presence of brood with the workers makes the periodic activity more pronounced. In this paper we investigate the effect that four categories of brood had on the periodic activity of worker ants. Eggs, small larvae, large larvae, and pupae were tested with four different-sized aggregates of workers. We hypothesized that brood care is responsible for the increase in periodic activity and therefore that larvae (which require more tending) would be more effective at increasing periodic activity than eggs or pupae. Contrary to our expectations, eggs and both size categories of larvae were equally effective in enhancing periodicity in our experimental aggregates. Pupae, in contrast, were completely ineffective at enhancing periodic activity. We discuss some possible reasons for the differential effects of eggs, larvae, and pupae on the behavior of worker ants.  相似文献   

19.
Phenological and some biological characteristics of Hippodamia (Adonia) variegata (Goeze) (Coleoptera: Coccinellidae), such as voltinism, hibernation, number of progeny produced by each generation, mating activity and sex ratio were studied, in order to evaluate the significance of this predator. The study of phenology was conducted in outdoor cages in Kifissia (Athens), during 1999--2001 and as prey was given Dysaphis crataegi (Kaltenbach). Hippodamia variegata completed seven generations between April and November. The hibernating population of H. variegata consisted of adults of 6th and 7th generations. The fecundity of the predator was studied under constant conditions [25 °C, 65% R.H. and 16:8(L:D)h photoperiod] in the laboratory and some population parameters were calculated: The total fecundity ranged between 789 and 1256 eggs, while the mean total fecundity was 959.6 eggs. The greatest proportion of eggs (45%) was oviposited in clutches of 11--20 eggs. The net reproductive value (R0) was found to be 425.9 females/female, the intrinsic rate of increase (rm) 0.178 females/female/day and the mean generation time (T) 34.0 days.  相似文献   

20.
【目的】为了测定多异瓢虫Hippodamia variegata(Goeze)成虫对枸杞木虱Paratrioza sinica Yang&Li的捕食作用。【方法】在室内测定了多异瓢虫的捕食功能反应、种内干扰、自身密度干扰、捕食偏好性,并通过罩笼试验研究多异瓢虫在田间对枸杞木虱的捕食效果。【结果】结果表明,多异瓢虫对枸杞木虱的捕食功能反应符合HollingⅡ型方程,对卵、1~2龄若虫、3~5龄若虫以及成虫的最大捕食量分别为80.4粒、410.0头、350.8头和102.5头。田间罩笼试验结果证明,在多异瓢虫成虫生长周期30 d内能使枸杞木虱总虫口密度下降85.4%;多异瓢虫对枸杞木虱成虫的搜寻效率a=0.8252为4种木虱虫态最佳,而对枸杞木虱卵处理时间Th=0.002283为4种木虱虫态中最佳;在100头/皿的猎物密度下多异瓢虫均能展现其最大捕食率,益害比参考值为1∶100。多异瓢虫对枸杞木虱的捕食作用受自身密度的影响显著大于种内干扰;在100头/皿混合猎物密度下,多异瓢虫更偏好木虱成虫,在300头/皿下,多异瓢虫更偏向于木虱若虫。【结论】研究表明,多异瓢虫是具有控制潜力的捕食性天敌,人工释放多异瓢虫成虫可有效防治枸杞木虱。  相似文献   

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