吡虫啉对异色瓢虫种群控害功能的影响

【目的】杀虫剂对天敌的非致死效应是杀虫剂安全性评估的重要内容。【方法】本研究以吡虫啉亚致死浓度处理的大豆蚜Aphis glycines饲喂异色瓢虫Harmonia axyridis,测定了异色瓢虫的发育历期、存活率、蛹重和捕食功能反应。【结果】异色瓢虫G0代不论从哪个龄期开始饲喂毒蚜,LC25(W)处理各龄期其发育均显著延长,且未成熟期(1龄至成虫)显著延长,蛹重和存活率显著降低;异色瓢虫G0代从1龄、3龄和4龄开始饲喂毒蚜,显著延长G1代的3龄龄期,显著缩短G1代的4龄龄期;G0代从4龄开始饲喂毒蚜,显著延长G1代1-3龄的发育历期;G0代不论从哪个龄期开始饲喂毒蚜,G1代蛹重都显著降低,G1代幼虫存活率无显著的变化;异色瓢虫对LC25处理的2龄、3龄和4龄幼虫的最大捕食量显著降低,其余组无显著变化。【结论】吡虫啉亚致死浓度对异色瓢虫G0代和G1代的生长发育均产生影响,且影响异色瓢虫的捕食能力,从而影响异色瓢虫种群的控害功能,这种杀虫剂对非靶标天敌昆虫的非致死效应需要在杀虫剂的安全性评估中予以考虑。     

不同龄期异色瓢虫对烟蚜的捕食潜能研究

异色瓢虫是烟田烟蚜的优势天敌种类之一,本文在室内进行了异色瓢虫成虫及各龄幼虫对烟草蚜虫的捕食功能反应试验,采用Holling-Ⅱ型功能反应模型进行拟合以明确其捕食潜能,利用Hassell模型和Watt模型拟合并测定了异色瓢虫种内干扰以及自身密度对烟蚜捕食作用的影响,结果表明:异色瓢虫各虫态对烟蚜的捕食量有明显的差异,在相同的烟蚜密度条件下,异色瓢虫4龄幼虫的日最大捕食量最大,为107.41头;其次是成虫,其日最大捕食量为94.34头;3龄幼虫、2龄幼虫和1龄幼虫的日最大捕食量分别为40.32头、14.25头和12.15头。在一定空间和相同比例猎物存在的条件下,种内干扰作用对1龄异色瓢虫幼虫的捕食量影响最为明显,干扰常数为1.1731,而对4龄幼虫干扰最小。各虫态自身密度对其捕食作用的干扰效应明显,1-4龄异色瓢虫幼虫以及成虫的竞争参数b值分别为0.5199、0.1848、0.1351、0.6757、0.6528。本研究表明异色瓢虫对烟蚜捕食潜力很大,尤其是4龄幼虫及成虫对烟蚜具有较大的捕食潜能。     

异色瓢虫对栗斑蚜的捕食作用

为明确异色瓢虫Harmonia axyridis对栗斑蚜Tuberculatus castanocallis的控害潜能,室内研究了异色瓢虫对栗斑蚜的捕食功能反应、寻找效应和干扰反应。结果表明：异色瓢虫对栗斑蚜的捕食功能反应均符合Holling-Ⅱ模型。异色瓢虫对栗斑蚜的日最大理论捕食量由大到小的排列顺序为4龄幼虫（447.97头）、雌成虫（387.53头）、雄成虫（379.73头）、3龄幼虫（243.45头）、2龄幼虫（122.75头）和1龄幼虫（62.62头）。异色瓢虫的寻找效应随着栗斑蚜密度的增加而降低。异色瓢虫随着自身密度的增加单头捕食量和捕食作用率逐渐减少,分摊竞争强度逐渐增大,符合Hassell干扰模型,不同虫态异色瓢虫其自身密度对栗斑蚜捕食作用均有明显的干扰效应,其干扰系数从大到小依次为4龄幼虫（0.7257）、雌成虫（0.6907）、雄成虫（0.6703）、3龄幼虫（0.6387）、2龄幼虫（0.3425）和1龄幼虫（0.3392）。结果表明异色瓢虫对栗斑蚜具有较好的控害潜力,为高效利用异色瓢虫田间防治栗斑蚜提供了理论依据。     

异色瓢虫对设施栽培桃树桃蚜的捕食功能反应研究

为明确异色瓢虫对设施栽培桃树上桃蚜的自然控制力,在室内研究了异色瓢虫成虫自身密度和不同蚜虫密度对捕食功能的影响。结果表明,异色瓢虫对桃蚜的捕食功能反应符合Holling-Ⅱ圆盘方程,其拟合模型为Na=0.898Nt/(1+0.0045Nt),每头异色瓢虫在1 d内对桃蚜的最大捕食量为200头,捕食每头桃蚜的处置时间Th=0.005d。异色瓢虫自身密度对桃蚜捕食作用有一定制约,拟合Watt竞争模型方程为A=86.441P-0.6592。     

异色瓢虫法国种群对豆蚜的捕食效应

异色瓢虫Harmonia axyridis(Pallas)的法国种群具有飞行能力较低的特点,在生物防治方面可能更具利用价值。为了使其更好的在田间应用,本文进行了异色瓢虫的法国种群各龄幼虫及雌、雄成虫对豆蚜的捕食功能比较研究。结果表明:各龄幼虫及雌、雄成虫对豆蚜捕食功能反应符合Holling II模型,检验各圆盘方程理论值和实测值拟合较好。同一虫态在不同空间水平对蚜虫的捕食能力有显著差异,在广口瓶处理中(较大空间),1～4龄幼虫及雌、雄成虫的最大理论捕食量分别为4.51、83.33、111.12、166.67、190及200头;不同虫期及成虫的瞬间攻击率a为3龄>4龄>雄虫>雌虫>2龄>1龄,且1龄的处理时间Th最长(0.2225);在培养皿处理中(较小空间),1～4龄幼虫及雌、雄成虫的最大理论捕食量分别为6.17、19.23、45.45、100、142.86、111.11头,不同虫期的瞬间攻击率a为2龄>3龄>雄虫>4龄>1龄>雌虫,且4龄的处理时间Th最长(0.1624)。     

异色瓢虫成虫对麦二叉蚜的捕食作用模型

通过异色瓢虫雌,雄成虫对麦二叉蚜捕食作用研究,得出：1．异色瓢虫雌、雄成虫对麦二叉蚜捕食作用的功能反应均是HollingⅡ型反应;2．异色瓢虫捕食麦二叉蚜时,同等数量的异色瓢虫雌雄混合的干扰作用大于同一性别成虫间的干扰作用;3．异色瓢虫雌、雄成虫均喜好捕食低龄若蚜．     

异色瓢虫对豆蚜的捕食功能反应

试验开展了异色瓢虫Harmonia axyridis Pallas对豆蚜Aphis craccivora Koch的捕食功能反应研究。结果表明,异色瓢虫各虫态的功能反应类型均属于HollingⅡ型。随着豆蚜数量的上升,异色瓢虫对豆蚜的捕食增加量逐渐减小直至趋于稳定。异色瓢虫各龄幼虫、成虫对豆蚜的寻找效应均随豆蚜数量的增加而减小。异色瓢虫4龄幼虫的a/Th值最大,为2255.67,捕食功能最强,其后为成虫、3龄、2 龄、1龄幼虫。     

异色瓢虫对白毛蚜捕食作用的研究

试验研究了异色瓢虫Leis axyridis(Pallas)各龄幼虫和戌虫对白毛蚜Chaitophorus po-pulialbae无翅成蚜的捕食功能反应及其成虫的寻找效应。功能反应均属Holling II型。异色瓢虫成虫寻找效应和自身密度之间的关系用Hasell & arley(1969)模型E=QP-m 和Beddington(1975)模型E=aT/［1+btm(P-1)]进行了模拟,Beddington模型更好地反映寻找效应和瓢虫密度之间的 关系。寻找效应与瓢虫成虫自身密度和蚜虫密度之间的关系用Bcddington(1995)模型E＝aT/[1+aT_mN十bt_m(P-1)]进行描述,表明寻找效应(E)随瓢虫密度(P)和猎物蚜虫密度(N)的增大而下降     

温度对异色瓢虫生长发育和繁殖的影响

为探索饲养异色瓢虫Harmonia axyridis（Pallas）的最适温度,了解其对高温的耐受性,组建了异色瓢虫在15,20,25,30和35℃下的实验种群生命表。结果表明：各虫态的发育速率随温度的升高而加快,在15℃下世代的发育历期最长（65.5d）,而30℃时仅为22.4d,20℃和25℃时分别为39.0d和23.0d。卵、幼虫、蛹和世代的发育起点温度分别为9.8,8.2,11.6和8.5℃,有效积温分别为41.1,225.6,81.6,432.6日.度。成虫寿命随温度升高而逐渐缩短,15℃时最长,为77.7d,在30℃下最短,为36.3d;单雌产卵量在25℃时最高,平均为2193.0粒,15℃时最低,为626.0粒。在25℃下,异色瓢虫的种群趋势指数和内禀增长力均较高,分别为916.7和0.15,表明25℃是异色瓢虫生长、繁殖的最适温度。     

异色瓢虫开发利用研究进展

异色瓢虫是一种重要的天敌资源,在许多国家都已成功应用于实践。本文概述了异色瓢虫的形态特征、生活史、习性及其开发利用有关方面的研究进展,并对现存的问题进行了讨论。     

Locomotory behavior of flightless Harmonia axyridis Pallas (Col., Coccinellidae)

To improve the efficiency of the ladybeetle Harmonia axyridis as a biological control agent against aphids, a flightless population was produced by feeding adults with a mutagen and selecting their progeny for non-flying but otherwise morphologically normal individuals. The inability to fly could result from a change in their flying behavior compared with control adults. Flight duration was very much shorter, wing beat frequency and more particularly the amplitude of the wing beats were clearly lower. More time was spent on the other components of flight behavior such as wing rotation, wing immobility and wing folding. The sequence of these patterns differed slightly mainly due to changes in their frequency. The locomotory behavior was not modified by the mutation, which only affected the wing muscles. The searching behavior of mutant adults differed from that of control adults only in that they took longer to encounter and ingest aphids. As this difference is not important, it should be possible to use this flightless population in biological control programs.     

Locomotor Behavior of Flightless Harmonia axyridis Pallas (Col., Coccinellidae)

To improve the efficiency of the lady beetle H. axyridis as a biological control agent against aphids, a flightless population was obtained by feeding adults with a mutagen and selecting their progeny for nonflying but otherwise morphologically normal individuals. These flightless adults attempted to fly but immediately fell. They softened their fall by opening their elytrae and wings. The inability to fly could result from change in their flying behavior compared to control adults. The flight duration was very much shorter, and the wing beat frequency and, more particularly, the amplitude of the wing beats were clearly lower. More time was spent in the other components of the flight behavior such as wing rotation, wing immobility, and wing folding. The sequence of these patterns differed slightly, due mainly to change in their frequency. The locomotor behavior was not modified by the mutation, which affected only the wing muscles. Searching behavior of mutant adults differed from that of control adults only in that they took longer to encounter and ingest aphids. Nevertheless, the larval growth and reproductive rate remained unchanged. The behavioral and biological features of these flightless adults indicate that it should be possible to use them in biological control programs.     

Influence of diet and photoperiod on development and reproduction of European populations of Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae)

The current study examines the effect of photoperiod (16:08 or 12:12 h L:D) and diet (eggs of Ephestia kuehniella Zeller (Lepidoptera: Phycitidae) or the pea aphid Acyrthosiphon pisum (Harris) (Hemiptera: Aphididae)) on the development and reproduction of the multicoloured Asian lady beetle Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae). A long-term laboratory population of H. axyridis (since 1998) and a melanic and non-melanic population originating from field collected individuals of H. axyridis in Belgium were used in this study. Long day conditions (16 h photoperiod) shortened development of the field populations with 2–3 days when compared with short day conditions (12 h photoperiod). Oviposition in the field populations was delayed by 1–3 months when reared at a 12 h photoperiod. Dissections indicated that the females were in reproductive diapause. As compared with live pea aphids, a diet consisting of E. kuehniella eggs yielded heavier adult body weights (up to 12%) and increased the number of egg laying days (by 45–169%) for both field populations at a 16 h photoperiod and lengthened adult life span (by 45–92%) under both light regimens. The morph types differed in their response to the foods offered in terms of developmental rate, pre-oviposition period and number of oviposition days. The laboratory and field strains responded differentially to regimens of food and photoperiod. The study indicated a greater nutritional plasticity of the non-melanic morphs which may offer them a competitive advantage that may in part explain the predominance of non-melanic morphs in newly colonized areas.     

异色瓢虫热休克蛋白70基因的克隆与分析

本研究通过RT-PCR和RACE方法,首次克隆了异色瓢虫Harmonia axyridis(Pallas)热休克蛋白70(HSP70)cDNA全序列(GenBank登录号:EF668009).获得的cDNA全长2200 bp,其中开放阅读框1956 bp,编码一个651氨基酸的蛋白,计算分子量为70 kDa,等电点(PI)为5.32.同源序列比对结果表明,异色瓢虫HSP70与其它真核生物的HSP/HSC70有着较高的序列同源性(85%～93%).其中与赤拟谷盗Tribolium castaneum热休克蛋白70(HSP70)同源性最高,达到93%.与其它真核生物HSP70一样,该序列包含真核生物HSP70高度保守的全部三个家族标签以及ATP/GTP结合位点、一个Bipartive nuclear localization signal和细胞核定位信号.     

Expansion of Harmonia axyridis Pallas (Coleoptera: Coccinellidae) to European Russia and adjacent regions

An invasive alien species, the harlequin ladybird Harmonia axyridis (Pallas, 1773), has quickly expanded its distribution in Eastern Europe. Records of H. axyridis from 31 localities in Lithuania, Latvia, the Ukraine, European Russia, and the Northern Caucasus are summarized and mapped. Within the last few years this species has established in south Latvia, on the Baltic Sea shore (Kaliningrad oblast and Lithuania), in the western and central Ukraine, Crimea, and in the Northern Caucasus. Besides that, individual specimens have been found in 4 more localities in European Russia. The species is recorded from Lipetsk oblast (European Russia), Crimea, and Nikolaev oblast (the Ukraine) for the first time.     

Role of long-chain hydrocarbons in the aggregation behaviour of Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae)

The multicoloured Asian ladybirds, Harmonia axyridis (Pallas), form large aggregations inside dwellings to survive cold winters, causing annoyance to householders due to their abundance, allergenic properties and problems consequent on reflex bleeding. Flight to overwintering sites and macrosite choice of this species is well documented. H. axyridis shows a hypsotactic behaviour and a clear preference for contrasting visual elements. However, how the microsite is selected remains undocumented, although a better understanding of the factors implicated could lead to the development of new control methods for this pest. In this work, we hypothesised that non-volatile compounds are involved in the microsite choice and aggregation of this beetle. Long chain hydrocarbons were identified at aggregation sites, comprising saturated and unsaturated homologues. An aggregation bioassay was then conducted on overwintering individuals, highlighting the retention capacity of the identified compounds on the tested ladybirds. Additional investigations showed that H. axyridis males and females, originating from overwintering sites, deposit a similar blend of molecules while walking. A Y-shaped tube assay revealed that this blend is used by male and female congeners as cue allowing individuals to orientate towards the treated side of the olfactometer. These results suggest the use of two different blends of long chain hydrocarbons by H. axyridis during its aggregative period, the first one to lead conspecifics towards aggregation sites (microsites) and the second to ensure the cohesion of the aggregation. These findings support the potential use of these blends, in association with volatiles, in the design of traps in order to control infestations of this species in dwellings.     

Invasions by Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae) in the Western Hemisphere: implications for South America

The multicolored Asian lady beetle, Harmonia axyridis (Pallas), native to Asia, has recently been detected in South America after successfully invading North America and Europe. This coccinellid is a voracious predator; therefore, it is popular and effective in biological control. Unfortunately, H. axyridis also has associated adverse impacts (i.e., as a household pest, pest of fruit production, and threat to non-target organisms). To predict the potential geographic extent of impacts of H. axyridis in South America we review the history of its invasion in the Western Hemisphere and address various factors critical to the future invasion (i.e., arrival, establishment, and spread) of new areas of South America. The likelihood of continued introductions (i.e., arrival) of H. axyridis to South America seems high, due to its popularity as a biological control agent and through accidental introductions. Establishment also seems likely in broad regions of South America. Climate matching with the native range suggested that much of southern South America may be suitable for establishment. In contrast, habitat matching with the native range suggested that northern South America may be more suitable. In addition, prey availability should not limit establishment of this predator. Once established, H. axyridis seems likely to spread by flight and human-assisted means. Overall, the invasion of H. axyridis over broad areas in South America seems likely.