Ecology and Control of Erinnyis ello and E. alope,Important Insect Pests in the New World

Abstract

The sphingid moth Erinnyis ello L. is an important pest of cassava and the most serious pest of the rubber tree in the New World; E. alope Drury is sometimes a serious pest of papaya. Information on the known food plants, life cycle, behaviour, natural enemies, seasonal abundance and present methods of control of these two lepidopterous pests is reviewed. The perspectives for improved control of E. ello with special reference to rubber plantations in Brazil, through the manipulation of natural enemies, a more rational use of insecticides and the adoption of certain cultural methods, are discussed.     

Wheat (Triticum aestivum L.)‐based intercropping systems for biological pest control

Wheat (Triticum aestivum L.) is one of the most cultivated crops in temperate climates. As its pests are mainly controlled with insecticides that are harmful to the environment and human health, alternative practices such as intercropping have been studied for their potential to promote biological control. Based on the published literature, this study aimed to review the effect of wheat‐based intercropping systems on insect pests and their natural enemies. Fifty original research papers were obtained from a systematic search of the peer‐reviewed literature. Results from a vote‐counting analysis indicated that, in the majority of studies, pest abundance was significantly reduced in intercropping systems compared with pure stands. However, the occurrence of their natural enemies as well as predation and parasitism rates were not significantly increased. The country where the studies took place, the type of intercropping and the crop that was studied in the association had significant effects on these results. These findings show that intercropping is a viable practice to reduce insecticide use in wheat production systems. Nevertheless, other practices could be combined with intercropping to favour natural enemies and enhance pest control. © 2016 Society of Chemical Industry     

Temporal dynamics of the arthropod community in pear orchards intercropped with aromatic plants

BACKGROUND: Increasing attention has been paid to enhancing biological control through habitat management in agricultural systems for enhanced pest management. Pest management benefits can be realised by intercropping, which can increase natural enemy abundance and, in turn, reduce pest abundance. In this study, the composition and temporal dynamics of arthropod communities in pear orchards when intercropped with aromatic plants were investigated, and the effectiveness and applicability of aromatic plants as intercrops for enhancing insect control were assessed. RESULTS: When compared with natural grasses or clean tillage, intercropping significantly reduced pest abundance and increased the ratio of natural enemies to pests. Intercropping also shortened the occurrence duration and depressed the incidence peak in annual dynamics curves of the pest subcommunity and the arthropod community, mainly because of the repellent effects of aromatic plants. Equally important, intercropping significantly reduced the numbers of major pests, such as Psylla chinensis, Aphis citricola and Pseudococcus comstocki, while their incidence period was delayed to varying degrees, and the numbers of their dominant natural enemies (Coccinella septempunctata, Phytoseiulus persimilis and Chrysoperla sinica) increased. CONCLUSION: Intercropping with aromatic plants led to a considerable improvement in arthropod pest management by enhancing the activity of the beneficial arthropod community within the pear orchard ecosystem. Copyright © 2011 Society of Chemical Industry     

The effects of intercropping with cereals and minimal permethrin applications on insect pests of cowpea and their natural enemies in Nigeria

Abstract

Major insect pests and their natural enemies were sampled on cowpea in monocrop and cereal intercrop plots in southern and northern Nigeria. Populations of flower thrips, Megalurothrips sjostedti (Trybom), were reduced by 42% and predators, mostly Orius spp. (Anthocoridae), by 23% on cowpea in maize intercrop plots at Ofiki in the south. Infestation by pyralid pod borer, Maruca testulalis Geyer, was unaffected by cropping system. The results suggest that tasselling maize attracts flower‐eating beetles (Meloidae) to intercrop plots, and that pod‐sucking Hemiptera were increased by cereal intercrops at Yankara in the north. Three u.l.v. applications of permethrin at 150 g a.i./ha to monocrop cowpea reduced pest populations by 50 to 85% in the south and increased yield sevenfold. However, the sprayed crop in the north was lost due to a heavy infestation of pod‐sucking bug, Clavigralla tomentosicollis Stål, and outbreaks of Aphis craccivora Koch on sprayed plots in both localities suggested damage to natural enemies. It is concluded that the pest management potential of intercropping is variable and dependent on environmental factors, but it is recommended that intercropping be used in integrated pest management systems with the progressive decrease in insecticide use.     

Biological control of exotic pests in Italy: recent experiences and perspectives1

In Italy, successful application of classical biological control began in the 20th century, when Berlese released the predator Rodolia cardinalis in 1901 and the parasitoid Encarsia berlesei in 1906. Later, the ‘inoculative’ method was applied many times, limiting the misuse of insecticides and therefore achieving very positive effects for both the agricultural economy and environmental protection. When the establishment of new natural enemies failed, some exotic pests continued to damage important crops, sometimes disrupting any possibility of applying Integrated Pest Management (IPM). In other cases, new associations between exotic pests and native natural enemies occurred spontaneously and the importation of new species was not necessary: when no broad-spectrum plant protection products are applied, some palaearctic parasitoids, such as Diglyphus isaea, naturally control the imported American leafminers Liriomyza trifolii and L. huidobrensis and some native predators (mainly Orius spp.) often control the exotic western flower thrips Frankliniella occidentalis. However, the introduction of natural enemies from the area of origin of the exotic pest is often the only alternative to chemical insecticides. Since its introduction in 1979, the American Flatid, Metcalfa pruinosa, has been spreading annually into new areas of the Mediterranean, causing severe damage to many crops because none of the indigenous natural enemies are sufficiently effective. Therefore, only the introduction of exotic natural enemies, such as the parasitoid Neodryinus typhlocybae, may reduce the outbreaks.     

Note: First record ofGaleruca tanaceti in organicOriganum vulgare in Crete

The tansy leaf beetleGaleruca tanaceti (L.) is recorded for the first time in Crete as a pest of oreganoOriganum vulgare (L.). Oregano is an important herb extensively cultivated both in Crete and mainland Greece. The absence of serious pests due to the production of phenolic compounds and essential oils in the plant tissue has promoted the organic cultivation of oregano.G. tanaceti is a pest of herbaceous plants that has developed appropriate behavioral and biochemical strategies to circumvent host plant defences. In addition, the tansy leaf beetle has very few natural enemies and may pose a serious threat to the organic oregano crops, unless extensive studies of the biology and integrated control of the pest are undertaken. http://www.phytoparasitica.org posting Sept. 18, 2006.     

有机桃园天敌与蚜虫的互作关系及生态调控措施

蚜虫是有机桃园早期的主要害虫类群,为研究蚜虫与天敌的互作关系及生态调控措施,在基地内设计了地表种植大蒜+覆盖地膜、种植100%紫花苜蓿和70%紫花苜蓿+30%夏至草3种生态调控模式,调查昆虫群落的变化,分析蚜虫的主要天敌及生态调控措施的效果。结果表明,桃蚜、桃粉蚜和桃瘤蚜的主要天敌分别为龟纹瓢虫、小花蝽和七星瓢虫。蚜虫数量与益害比呈显著负相关关系。与对照处理相比,种植100%紫花苜蓿处理小区和种植70%紫花苜蓿+30%夏至草处理小区,益害比和天敌群落均匀度指数均显著升高,蚜虫总体数量显著降低。果园种植100%紫花苜蓿可以有效降低桃蚜数量;种植70%紫花苜蓿+30%夏至草可以有效降低桃蚜、桃粉蚜、桃瘤蚜3种蚜虫的种群数量。     

新疆春播玉米节肢动物群落结构及时序动态

通过探讨春播玉米节肢动物群落结构和时序动态,旨在为玉米田天敌保护利用及玉米害虫的合理防控提供基础资料。采用网捕法和目测法探明春播玉米节肢动物群落结构和时序动态。调查共获节肢动物7632头,隶属3纲12目45科66属70种,亚洲玉米螟Ostrinia furnacalis（Guenée）和玉米三点斑叶蝉Zygina salina Mit为本地区害虫优势种,天敌优势种则为多异瓢虫Hippodamia Variegata（Goeze）、方斑瓢虫Propiylaea quatuordecimpunctata（Linnaeus）、黄褐新园蛛Neoscone doenitzi（Boes.et Str.）、中华草蛉Chrysopa sinica Tjeder和十三星瓢虫Hippodamia tredecimpunctata（Linnaeus）。新疆北部春播玉米田节肢动物群落中植食性亚群落结构特征指数N、H'、J'、D与总群落相近,优势种害虫亚洲玉米螟和玉米三点斑叶蝉的大量发生致使玉米田节肢动物群落特征指数出现显著变化,是影响群落稳定的主要因素。主成分分析表明,捕食性节肢动物物种数、个体数和植食性节肢动物物种数累计贡献率可达61.47%,是影响该地区玉米田节肢动物群落结构变化的主导因子。灰色系统分析则表明,优势种天敌方斑瓢虫、草蛉、黄褐新园蛛种群数量的变化与优势种害虫玉米螟和玉米三点斑叶蝉种群数量的变化关联度最高,其关联度分别为0.7719和0.8778、0.7898和0.8309、0.9637和0.8312。天敌的发生与害虫种群数量的变化具有显著的跟随效应,这为合理保护利用天敌防控玉米害虫具有重要意义。     

Short-term toxicity of insecticides residues to key predators and parasitoids for pest management in cotton

The cotton ecosystem comprises various arthropod pest and natural enemies with simultaneous occurrence irrespective of growing region. The use of insecticides with reduced impact on natural enemies is a major goal to conserve them and, therefore, to reduce populations of arthropod pests. The survival of twelve key natural enemies for cotton pest management exposed to dried residues using the highest and lowest recommended rates representing old and new insecticides recommended to control cotton pests (chlorantraniliprole, chlofernapyr, spinosad, lambda-cyhalotrin, methidathion, pymetrozine, and thiamethoxam) was determined. The study included parasitoids [Aphelinus gossypii Timberlake, Bracon vulgaris Ashmead, Lysiphlebus testaceipes (Cresson), Telenomus podisi (Ashmead), Trichogramma pretiosum (Riley)] and predators [Hippodamia convergens Guérin-Méneville, Euborellia annulipes (Lucas), Podisus nigrispinus (Dallas), Solenopsis invicta Buren), Orius insidiosus (Say), Chrysoperla externa Hagen and Eriopis connexa (Germar)], with two different cohorts for these last two species. All natural enemies exposed to methidathion exhibited 100% mortality. Thiamethoxam, lambda-cyhalothrin and chlorfenapyr also caused high mortality of P. nigrispinus, S. invicta, H. convergens, O. insidiosus and all tested parasitoids. Among the natural enemies, E. annulipes exhibited high survival when exposed to all tested insecticides, except methidathion. Chlorantraniliprole and pymetrozine caused overall lower impact on the natural enemies tested followed by spinosad; hence, they are options for cotton pest management. Furthermore, the outcomes highlight the implication of knowing the background susceptibility of the species tested when addressing the impact of insecticides on natural enemies.     

Fecundity ofEurydema ornatum feeding on a variety of seeds under laboratory conditions

The egg parasitoidTrissolcus spp. is the natural enemy of the cabbage bug,Eurydema ornatum L. (Het., Pentatomidae), a destructive pest of cultivated and wild Crucifera. Its preferred host is the wheat bugEurygaster integriceps Put., the most important pest of wheat. In order to rear the parasite for biological control purposes, mass production of its hostE. ornatum is suggested. In a laboratory study, the fecundity ofE. ornatum feeding on garden cress and radish was significantly higher than on red cabbage, white cabbage, rape or cauliflower. The oviposition period was significantly longer on garden cress and radish than on the other Crucifera. There was no difference among the various Crucifera in terms of length of postoviposition period or number of eggs laid per female per day.     

黄秋葵田主要害虫、天敌种群动态及时间生态位分析

为了解黄秋葵田害虫和天敌的种类及种群动态变化情况,分析主要害虫和天敌间的生态调控机制,为黄秋葵田害虫的生物防控提供科学依据。通过目测法和5点取样法调查记录黄秋葵田害虫、天敌种类和数量,并对害虫和天敌间的生态位进行分析。结果表明,黄秋葵田内共发现6目13科21种昆虫,害虫优势种分别为棉蚜和棉大卷叶螟,两者在田间均呈聚集分布。天敌优势种分别为龟纹瓢虫、异色瓢虫、三突花蛛、草间小黑蛛、卷叶螟绒茧蜂、卷叶螟姬小蜂。其中蚜虫生态位宽度值最小,田间发生时间比较集中,主要在6月。棉大卷叶螟生态位宽度值最大,田间发生时间比较长,主要在7—9月。蚜虫与瓢虫的时间生态位重叠值为0.8593,瓢虫对蚜虫有明显的跟随效应,是蚜虫的优势性天敌。棉大卷叶螟与蜘蛛、卷叶螟绒茧蜂、卷叶螟姬小蜂的时间生态位重叠值分别为0.7220、0.7175、0.6797,这三类天敌对棉大卷叶螟有明显的跟随效应,对其种群具有协同控制效果,是控制棉大卷叶螟的三种优势天敌。以上结果表明,天敌对害虫在时间生态位上有一定的同步性,在田间管理时应加强对这些天敌的保护和利用,以增强天敌的自然控害功能。     

Predators with a future as bioagents against glasshouse pests1

As a result of the application of Encarsia formosa, Phytoseiulus persimilis and Bacillus thuringiensis, and of the decreased use of pesticides, we have observed the spontaneous appearance of natural enemies not normally present in Bulgarian glasshouses. Clitostethus arcuatus has proved a competitive species with E. formosa on Nicotiana glauca, green capsicum and Hibiscus syriacus, attacked by Trialeurodes vaporariorum. On cucumber and capsicum plants infested respectively by Aphis gossypii and Myzus persicae, Cryptolaemus montrouzieri was established after spontaneously entering an experimental glasshouse. Some trials were carried out with the polyphagous bug Podisus maculiventris under laboratory conditions. It was able to use larvae of T. vaporariorum, M. persicae and A. gossypii as prey. On this basis, it seems quite promising to include this predator in IPM programmes as an additional bioagent against certain glasshouse pests during the autumn-winter-spring period.     

The Potential of Semiochemicals for Control of Phorodon humuli (Homoptera: Aphididae)

Field experiments employing yellow water-traps with vials releasing methyl salicylate, butyl isothiocyanate, 4-pentenyl isothiocyanate and diethyltoluamide were conducted during the spring migration of Phorodon humuli (Schrank), with the aim of identifying substances which might be used in the field to deter landing on hop plants. Methyl salicylate and the two isothiocyanates reduced trap catches of P. humuli. During the spring of 1994 a slow-release formulation of methyl salicylate and a β-acid-rich hop resin sprayed on to hop plants did not reduce aphid infestations significantly. In autumn cis,cis-nepetalactol, the main component of P. ‘humuli’s sex pheromone, prepared by various synthetic routes, increased trap catches of males and gynoparae equally. Catches of males in pheromone traps situated in a hop garden decreased with increasing trap height. Catches of males in traps charged with increasing doses of the cis,cis-nepetalactol peaked at 1 mg and then plateaued, whereas catches of gynoparae peaked similarly at 1 mg and then decreased. The effects of kairomones from an extract of the primary host, sex pheromone and a visual cue from yellow compared with clear water-traps were additive. The prospects for developing a semiochemicals-based control strategy against P. humuli, using some or all of the above elements, are discussed.     

Management strategies of mealybug pests of citrus in mediterranean countries

Six mealybug species have been reported as citrus pests in the Mediterranean Basin: the citrus mealybugPlanococcus citri (Risso), the citriculus mealybugPseudococcus cryptus Hempel, the longtailed mealybugPseudococcus longispinus (Targioni-Tozzetti), the citrophilus mealybugPseudococcus calceolariae (Maskell), the obscure mealybugPseudococcus viburni (Signoret) and the spherical mealybugNipaecoccus viridis (Newstead). Some of these species,e.g. N. viridis, have recently been introduced into the region and are still spreading. Mealybugs are usually occasional or minor pests of citrus, but some species can reach key pest status. Mealybug management strategies in citrus have been based mostly on classical biological control and, to a lesser extent, on augmentative releases. However, chemical control is widely used, mainly because of the poor adaptation of the principal natural enemies to the climatic conditions of the Mediterranean. The application of pheromones is still restricted to monitoring the citrus mealybug, whose sex pheromone is commercially available. Mass trapping and mating disruption should be considered for possible use in IPM programs as an alternative method to supplementary chemical treatments. Enhancement of biological control through management of ant populations is another promising tactic for control of mealybugs. Strategies for managing mealybug pests of citrus, and possible levels of integration of different tactics according to the pest status, are discussed. http://www.phytoparasitica.org posting Oct. 3, 2004.     

Bt棉田中绿盲蝽防治技术的研究

通过设置转Bt棉综防田(种植诱集作物和适当使用农药控制害虫)、对照田(依靠自然天敌控制害虫)和化防田(使用农药控制害虫)3种处理,研究了冀南棉区绿盲蝽与捕食性天敌种群关系及绿盲蝽对棉花生长的影响。结果表明,在Bt棉田,绿盲蝽分别于6月29日、8月14日和9月4日出现了3个发生高峰。其中6月29日综防田、对照田和化防田百株发生量差异不显著(p>0.05);8月14日,对照田的百株虫量显著多于化防田和综防田。差异极显著(p<0.01);9月4日,对照田的虫量达到60头/100株,且不同类型田差异显著(p<0.05)。Bt棉生长前期和中后期,捕食性天敌在综防田的百株天敌量明显高于化防田和对照田,其中6月29日、8月29日和9月9日综防田的天敌量达65、70、75头/100株。分析3种不同类型田绿盲蝽对棉花叶危害株率、落蕾率、落铃率和成铃量影响顺序均为对照田>化防田>综防田,除化防田与综防田的落铃率无显著差异,其余均表现差异显著。     

广西忻城县山银花病虫害及其天敌昆虫种类调查

为明确广西忻城县山银花病虫害及其天敌昆虫种类,为当地山银花病虫害防治和天敌的保护利用提供参考,2008年-2010年系统调查了广西忻城县山银花病虫及主要病虫天敌发生情况,并进行了种类鉴定.结果表明,广西忻城县山银花害虫有35种,病害11种,天敌昆虫28种,其中主要害虫的捕食性天敌有24种,寄生性天敌2种,取食白粉菌的瓢虫有2种.此外,本文还综述了广西忻城县山银花主要病虫害‘三虫一病’的特征、发生规律及防治方法.     

新疆南部地区棉田捕食性天敌种群动态

为开展棉田害虫生态控制,于2004年5～8月系统调查了新疆阿克苏棉区捕食性天敌的种群数量消长动态。结果表明:该地区捕食性天敌种类多数量大,有7目15科28种以上,高峰期天敌虫量平均达到8.86头/株;无干扰情况下能建立稳定的自然种群,对棉田发生的害虫基本上可有效控制;不同天敌田间消长动态存在差异,瓢虫和草蛉为优势种类。     

Homothallism in Pseudoperonospora humuli

The downy mildew pathogen, Pseudoperonospora humuli, forms oospores abundantly in diseased hop tissue. Diverse monosporangial isolates of P. humuli derived from samples collected in Japan, Germany and the USA readily formed oospores within hop leaves when inoculated singly, suggesting homothallism. Single zoospore isolates also readily formed oospores within hop leaves, further supporting the homothallic nature of this oomycete. The majority of oospores were deemed viable based on cytoplasm characteristics and plasmolysis assays. However, disease symptoms failed to develop when hop leaves were inoculated with newly formed oospores, even when oospore conditioning was attempted with treatment with potassium permanganate or β‐glucuronidase/arylsulphatase, brief exposure to freezing temperature, or passage through an earthworm. Oospores derived from a monosporangial isolate of P. humuli that overwintered outdoors in infested leaves buried in soil also failed to cause downy mildew. Pseudoperonospora humuli is homothallic and oospores of the organism appear to require as yet unknown conditions to stimulate their germination and/or infection.     

保护利用农田天敌的群落问题探讨

作者在群落水平上,从5个方面探讨了保护利用农田天敌的理论基础。增加农田生态系统的多样性,可以增加天敌群落种库的多样性,进而加速天敌群落的迅速重建和发展,这对控制早期迁入害虫的发生有重要意义。多样性高的天敌群落能减轻害虫发生程度,推迟害虫发生高峰的出现。群落内各子系统的相互联系和相互作用维持了天敌群落的稳定,增强了天敌对害虫的控制作用。群落多样性是影响稳定性的一个重要因素,它在一定程度上反映稳定性。     

贵州省黔东南地区发现草地贪夜蛾的5种寄生性天敌及其两种重寄生蜂

迁飞性重大农业入侵害虫草地贪夜蛾Spodoptera frugiperda(J. E. Smith)于2019年入侵贵州省黔东南地区。深入研究害虫的天敌发生情况有利于发掘和利用天敌资源开展生物防治工作。本文将贵州省黔东南地区采集的被寄生卵块和幼虫置于实验室条件下饲育,利用DNA条形码技术鉴定羽化出的天敌昆虫。共鉴定出5种寄生性天敌昆虫,其中卵寄生蜂为夜蛾黑卵蜂Telenomus remus,幼虫寄生蜂为菜粉蝶盘绒茧蜂Cotesia glomerata和半闭弯尾姬蜂Diadegma semiclausum,幼虫寄生蝇为厉寄蝇属寄生蝇Lydella sp.和日本追寄蝇Exorista japonica。另外,还发现了两种寄生于菜粉蝶盘绒茧蜂的重寄生蜂,分别为弯沟啮小蜂属寄生蜂Baryscapus sp.和吉氏金小蜂Nasonia giraulti。本文的发现为筛选防治草地贪夜蛾的优势天敌奠定了基础。