栎空腔瘿蜂及其天敌长尾小蜂种群数量消长动态

栎空腔瘿蜂Trichagalma acutissimae(Monzen)是危害栓皮栎Quercus variabilis Blume叶片的重要林业害虫,为我国新纪录种。近年来,在南太行山区的栓皮栎林内暴发成灾,长尾小蜂Torymus sp.是栎空腔瘿蜂的一种主要寄生性天敌,为明确栎空腔瘿蜂及其天敌长尾小蜂种群数量消长动态,为预测预报和综合治理提供依据,本文调查了栎空腔瘿蜂和长尾小蜂成虫种群动态以及长尾小蜂的寄生率。结果表明,长尾小蜂成虫种群数量及寄生率一年发生2个高峰,第1个高峰发生在5月中旬,第2个高峰发生在7月下旬;2011—2015年,无性世代虫瘿平均每株发生的数量分别为826.0、816.4、61.8、11.0和3.4个,平均每块粘虫板长尾小蜂成虫发生数量分别为39.00、46.33、19.30、13.33和8.30头,长尾小蜂总寄生率分别为39.7%、51.0%、61.1%、54.9%和29.5%。     

缢管蚜小蜂调查初报

缢管蚜小蜂Aphelinus rhopalosiphagus Yang et Chen是根型蚜红腹缢管蚜的专性寄生蜂。1989年调查,该蜂对红腹缢管蚜寄生率31.37～84.03％。1993～1994年在文山陆稻区系统调查,该蜂在陆稻上始见于6月中旬,终见于11月中旬,寄生高峰集中在7月上旬～8月上旬;高峰期寄生率达55.28～80.75％。冬季缢管蚜小蜂主要分布在海拔740～1289M菜园地、麦田地,寄生于取食棒头草、看麦娘、冬小麦根部的红腹缢管蚜。     

中华长尾小蜂种群特性研究及成虫发生期预测

中华长尾小蜂是栗瘿蜂的专性寄生蜂,１ａ发生１代,因该蜂与寄主的食物链关系,使自然种群数量每６～８ａ出现１次变动周期。引起数量消长的主要因素有性比、过寄生现象、重寄生现象、幼虫期死亡和成虫羽化死亡等。本文还利用成蜂羽化进度与日期、积温和栗芽伸长的相关关系建立中华长尾小蜂发生期预测曲线,应用表明该预测曲线与实际情况吻合。     

花椒波瘿蚊寄生蜂——广肩小蜂田间发生规律研究

广肩小蜂Eurytoma sp.是花椒波瘿蚊Asphondylia zanthoxyli bu & Zheng的重要寄生天敌.广肩小蜂1年发生3代,以蛹在花椒波瘿蚊为害形成的虫瘿内越冬.第2年花椒发芽后在4月中旬越冬代成虫羽化;第1代成虫6月上旬羽化;第2代成虫8月上旬羽化.成虫产卵于花椒波瘿蚊幼虫为害后形成的虫瘿内;孵化后外寄生于花椒波瘿蚊幼虫,将寄主幼虫吃光后化蛹.越冬代寄生率达48.39%,第2年花椒发芽前剪除虫瘿枝可有效保护广肩小蜂种群数量.     

桉树枝瘿姬小蜂危害程度分级方法研究

桉树枝瘿姬小蜂Lepcocybe invasa Fisher ＆ La Saller对林木的危害程度因寄主品种、侵入时间、寄主生长阶段不同而有差异。依据该虫发生区的调查结果,阐述了桉树枝瘿姬小蜂危害程度的几种分级方法,以在实际操作中完善与应用,为森防检疫、测报和防治提供依据。     

桉树枝瘿姬小蜂生物学特性及控制技术

桉树枝瘿姬小蜂Leptocybe invasa Fisher & LaSalle为2000年新发现的一新属新种,2007年在我国首次发现.该虫为桉树的重要致瘿害虫,严重为害桉树幼林和苗木,可造成巨大损失.为了采取有力预防措施,本文论述该害虫的分类地位、形态特征、生物学特性、国内外发生现状,对其进行了风险分析与评估,依据目前掌握的资料及害虫发生特点,提出了相应的控制技术.     

桉树枝瘿姬小蜂综合防控技术的研究进展

桉树是我国三大速生用材树种之一,在制浆造纸和人造板产业中发挥着重要的作用,已成为我国林业经济的重要支柱产业。然而,外来入侵害虫桉树枝瘿姬小蜂在我国南方桉树种植区大面积致瘿为害多种桉树树种,致使苗木落叶、植株矮化、枝梢枯死,严重影响桉树的生长和产量,且目前尚无有效的防治措施。鉴于此,文章综述了国内外针对其已开展的综合防控技术,提出了以林业技术和生物防治为主,化学防治为辅的观点,以期为后续针对桉树枝瘿姬小蜂的有效防控提供参考资料。     

鄂北地区栗瘿蜂综合防治技术研究

栗瘿蜂在鄂北地区一年发生一代,以初龄幼虫在被害芽内越冬。翌年4月上旬栗芽萌动时开始为害,使被害芽形成虫瘿抑制新梢生长,导致减产甚至绝收。当地该瘿蜂优势种天敌是中华长尾小蜂,益害比1∶5时能抑制栗瘿蜂的大发生。以冬季清园铲除杂草,剪除病虫枝等农业防治为基础,收集虫瘿于3月下旬挂于栗园保护天敌为主导,辅之以化学防治的综合防治措施能有效地控制栗瘿蜂的为害。     

我国发现外来入侵害虫桉树叶瘿球角姬小蜂的重要天敌——桉树扁角金绿姬小蜂（膜翅目：姬小蜂科）

近年来,在我国桉树上发生了一种严重的外来入侵害虫——桉树叶瘿球角姬小蜂Ophelimus maskelli (Ashmead)（膜翅目：姬小蜂科Eulophidae）,其在桉树叶片上形成密密麻麻的小疱状虫瘿,造成桉树叶片大量脱落。为了利用天敌对该害虫进行生物防治,我们开展了该害虫的天敌调查。通过采集受害桉树叶片进行饲养,获得了一种寄生该害虫的寄生蜂——桉树扁角金绿姬小蜂Closterocerus chamaeleon(Girault)（膜翅目：姬小蜂科Eulophidae）。该寄生蜂为我国新纪录种,本文对其形态特征进行了详细描述,并提供了成虫鉴别特征的彩色照片。桉树扁角金绿姬小蜂原产地是澳大利亚,现在已被引进到世界上许多桉树栽培的国家和地区防治桉树叶瘿球角姬小蜂,防效十分显著。桉树扁角金绿姬小蜂是自然控制该害虫的优势天敌,我国现在发现了这种天敌,将在我国生物防治这种桉树外来入侵害虫上发挥重要作用。     

不同桉树品系对桉树枝瘿姬小蜂抗性研究

本研究选择了在我国主要桉树种植区内种植面积大或具有推广潜力的12个优良桉树品系,在广东肇庆、阳江和湛江3个样地进行抗桉树枝瘿姬小蜂试验,结果表明M1(Eucalyptus urophylla×E.tereticornis)、雷9(E.urophylla×E.tereticornis)为高抗品系,DH3229(E.urophylla×E.grandis)、DH3228(E.urophylla×E.grandis)、DH3226(E.urophylla×E.grandis)、LH1(E.urophylla×E.tereticornis)、金光21(E.jinguang No.21)、广3(E.wetarensis×E.marginata)和广林9(E.grandis×E.urophylla)等7个品系为抗虫品系,邓恩桉(E.dunnii)和雷11(E.urophylla×E.tereticornis)为感虫品系,Eg5(E.grandis)为高感品系。不同品系的感染虫瘿数量差异显著,Eg5的丛枝状等级较其它品系高,其它11个品系间的丛枝状等级也表现出不同程度的差异。     

辽宁省鞍山地区舞毒蛾天敌的研究

1992年在辽宁省鞍山、海城和岫岩县,共收集到舞毒蛾天敌36种,其中寄生性昆虫19种,捕食性昆虫15种,病毒和白僵菌各1种。在幼虫期,优势种是病毒、窄腹凹眼姬蜂和绒茧蜂,可杀死56.09±20.75％的幼虫。蛹期主要是寄蝇和麻蝇,追寄蝇数量占75％以上,总寄生率为31.21±20.87％。研究表明,天敌对控制舞毒蛾种群数量有重要作用。     

氮肥对水稻叶冠层捕食性天敌种群及其自然控制能力的影响

为了公正地评价氮肥对整个稻田生态系统的影响，在国际水稻研究所试验场分别设立0、100和200kg／hm^2三个氮肥水平，测定了水稻主要特性参数和叶冠层捕食性天敌的种群动态，同时以果蝇蛹作为替代猎物的方法在田间模拟评价了叶冠层捕食性天敌对害虫的自然控制能力。结果表明，虽然施用200kg／hm^2氮肥稻田的稻株高度、叶面积和稻草干重显著比施用100kg／hm^2氮肥稻田的高，但每丛分蘖数和稻谷产量则没有明显差异。在水稻叶冠层中，肖蛸、圆蛛、黑肩绿盲蝽、稻红瓢虫和捕食性螅等为稻飞虱主要捕食性天敌。肖蛸在水稻孕穗期的数量最高，圆蛛的种群随水稻的生长而下降，但黑肩绿盲蝽、稻红瓢虫和捕食性螅的数量却均随水稻的生长而增加。施用氮肥后稻田中肖蛸和稻红瓢虫的种群数量显著减少。在水稻孕穗期，叶冠层上蜘蛛网的数量和蜘蛛网总面积均随氮肥施用量的提高而显著减少。在水稻孕穗期和乳熟期，不施用氮肥稻田中的捕食性天敌对替代猎物果蝇蛹的捕食能力显著高于其它两个施用氮肥的稻田中的捕食能力。而在乳熟期施用100kg／hm^2氮肥稻田的捕食能力又显著比施用200kg／hm^2氮肥稻田的高。结果说明过量施用氮肥可削弱天敌对害虫的自然控制作用。     

沈阳地区美国白蛾的天敌复合体

为了更全面地了解美国白蛾Hyphantria cunea（Drury）的天敌种类,探究美国白蛾天敌复合体的组成以及天敌复合体中不同种群间的互作关系,为开展美国白蛾的生物防治提供新思路和新方法,本研究自2017年9月至2019年3月对中国沈阳地区的美国白蛾天敌开展了系统调查。结果显示：沈阳地区有33种美国白蛾天敌,其中,寄生性天敌14种,捕食性天敌19种。在国内首次发现锦州细颚姬蜂Enicospilus kigasirae（Uchida）、黄须盆地寄蝇Bessa remota（Aldrich）和黑须菲寄蝇Phebellia nigripalpis（Robineau-Desuoidy）3种天敌可以寄生美国白蛾幼虫。通过对美国白蛾各世代和虫态的天敌多样性等指标分析发现,沈阳地区美国白蛾天敌复合体优势种群由高到低为白蛾聚集盘绒茧蜂Cotesia gregalis Yang et You,康刺腹寄蝇Compsilura concinnata（Meigen）,白蛾周氏啮小蜂Chouioia cunea Yang。采用主成分分析的方法,对美国白蛾天敌复合体各世代与虫期进行综合评价和排序,结果表明美国白蛾天敌复合体在幼虫期复合程度较高,并且在第2代幼虫期复合程度达到最高。     

Can we forecast the effects of climate change on entomophagous biological control agents?

The worldwide climate has been changing rapidly over the past decades. Air temperatures have been increasing in most regions and will probably continue to rise for most of the present century, regardless of any mitigation policy put in place. Although increased herbivory from enhanced biomass production and changes in plant quality are generally accepted as a consequence of global warming, the eventual status of any pest species will mostly depend on the relative effects of climate change on its own versus its natural enemies' complex. Because a bottom‐up amplification effect often occurs in trophic webs subjected to any kind of disturbance, natural enemies are expected to suffer the effects of climate change to a greater extent than their phytophagous hosts/preys. A deeper understanding of the genotypic diversity of the populations of natural enemies and their target pests will allow an informed reaction to climate change. New strategies for the selection of exotic natural enemies and their release and establishment will have to be adopted. Conservation biological control will probably become the keystone for the successful management of these biological control agents. © 2013 Society of Chemical Industry     

The Identification and Exploitation of Resistance in Carrots and Wild Umbelliferae to the Carrot Fly, Psila rosae (F.)

Partial plant resistance to the carrot fly, Psila rosae, has been identified in several Nantes varieties of carrot, Daucus carota, which reduces larval damage to the roots and the number of pupae remaining in the soil after cropping by 50%. The resistance of the Nantes variety 'Sytan' was found to be consistent at 12 sites in 5 European countries over two seasons. The resistance has been shown to be based on antibiosis and correlated with concentrations of chlorogenic acid in the roots. The resistance complements cultural and chemical methods for controlling P. rosae. Thus, in field experiments over two seasons it was shown that carrots could be left in the ground for a longer period providing a greater sowing/harvesting interval with a resistant variety than a susceptible one because of the reduction in damage and the delayed development of insects on the resistant variety. In two seasons at two sites a partially-resistant variety required only one-third of the dose of insecticide to provide a marketable crop compared with a susceptible carrot variety. In a breeding programme involving the variety 'Sytan', male sterile lines, inbreds and selections with improved levels of resistance were developed. Much higher levels of resistance were identified in certain wild Daucus species and 15 years of crossing and selection produced lines with significantly higher levels of resistance than exists in the variety 'Sytan'. A range of resistant carrot material bred at Horticulture Research International has been released to seed companies for use in the production of improved carrot varieties. The partially-resistant variety 'Flyaway' was made available to amateur gardeners in 1993 and to commercial growers in 1995 as a result of this research.     

茶尺蠖生物防治进展

茶尺蠖Ectropis obiqua Prout是茶园中的重要害虫，对它的生物防治研究国内已做了较多的工作。本文从茶尺蠖的研究基础一大量饲养和它的病原性天敌、捕食性天敌、寄生性天敌及信息素等方面对茶尺蠖的生物防治研究作了综述。     

Integration of chemical and biological control systems for arthropods: Evaluation in a multitrophic context

The methods used to evaluate and categorise the effects of pesticides on beneficial arthropods are reviewed, including the potential significance of indirect, ‘sub-lethal’ activity and the importance of bioavailability of pesticides under semi-field or field conditions. Interspecific and intraspecific differences in the susceptibility of natural enemies (parasitoids and predators) to pesticides are considered, including the use of resistant strains in Integrated Pest Management (IPM) systems. The potential impact of pesticide resistance in the target pest on its natural enemies is also discussed. The need to assess the influence of the host plant/cultivar on the efficacy of pesticides for use in integrated control programmes (ditrophic effects) and of the possible effects of such chemicals on host plant/cultivar-pest-parasitoid systems (tritrophic effects) are then described with specific reference to the diamondback moth and key endolarval parasitoids. Finally, the potential for manipulation of tritrophic interactions to enhance parasitism by application of low doses of toxicants is demonstrated.     

Adapting sampling effort to assess the population establishment of Torymus sinensis,the biocontrol agent of the chestnut gallwasp

Torymus sinensis Kamijo is to date the most effective controlling agent of the chestnut gallwasp Dryocosmus kuriphilus. The procedure to evaluate the parasitism rate of T. sinensis consists of dissecting D. kuriphilus galls collected in the field and checking them for its presence. Such a procedure is, however, time-consuming. Using a space-for-time substitution approach, by creating a temporal gradient within 15 sites and by means of bootstrap simulations, we analysed the effect of different sampling efforts on the precision of evaluating the success of T. sinensis release and the evolution of its parasitism rate towards biocontrol. Results show that after the first release, 200 galls are required to assess its presence with a 1% failure rate. Once T. sinensis is established, 100 galls are generally sufficient to estimate its parasitism rate by accepting a (median) percentage of error of 14% in the second year and 6% and 3% in the third and fourth year, respectively. Finally, we propose a series of design options to reduce the sampling effort according to the targeted accuracy level and as a function of the obtained parasitism rate.