淡足侧沟茧蜂对甜菜夜蛾和斜纹夜蛾的寄生选择性研究

应用2因素2次回归正交旋转组合设计研究了淡足侧沟茧蜂Microplitis pallidipes对甜菜夜蛾Spodoptera exigua (Hubner)、斜纹夜蛾Spodoptera litura的寄生选择性,并建立了2种寄主共存时的被寄生模型.主效分析表明,甜菜夜蛾和斜纹夜蛾幼虫被寄生虫数均随寄主自身密度的增加而增加;淡足侧沟茧蜂对2种寄主无明显的选择性,对甜菜夜蛾、斜纹夜蛾幼虫共存时的选择寄生比率分别为0.5211、0.4788.在人工繁殖淡足侧沟茧蜂时,可以利用易于人工繁殖的斜纹夜蛾做为繁蜂寄主,提高淡足侧沟茧蜂的繁殖速度,降低繁蜂成本.在甜菜夜蛾、斜纹夜蛾发生期,可保护利用淡足侧沟茧蜂来控制蔬菜夜蛾.     

斑痣悬茧蜂的寄主种间选择性及其子代蜂发育适合度表现

为检验基于经典搜寻理论的最优膳食模型的预测——产卵雌蜂应该选择最适于子代蜂发育的寄主种进行产卵,本研究以斑痣悬茧蜂(Meteorus pulchricornis)及其寄主斜纹夜蛾(Spodoptera litura)和粘虫(Mythimna separata)的幼虫为材料,在控制寄主体型大小和龄期影响的基础上,分别在体型大小相近和日龄相同的3个水平上观察了斑痣悬茧蜂对2种寄主幼虫的选择偏好,并观察了子代蜂生长发育适应度表现。在观察期(1h)内,当2种寄主幼虫的体型相近或者龄期相同的情况下,斑痣悬茧蜂对粘虫的产卵器刺扎次数以及寄生率(用结茧率表示)均高于斜纹夜蛾;而在斜纹夜蛾幼虫体内发育出的子代蜂茧重和体型均大于粘虫,成蜂寿命无显著差异。最后,对斑痣悬茧蜂的寄主选择和子代发育表现不一致现象进行了讨论。     

斜纹夜蛾取食四种植物对马尼拉侧沟茧蜂发育和繁殖的影响

研究斜纹夜蛾Spodoptera litura幼虫取食4种植物后对马尼拉侧沟茧蜂Microplitis manilae生长发育和繁殖的影响,为利用该蜂开展斜纹夜蛾的生物防治提供理论依据。在人工气候箱内(26℃±1℃、RH 65%±5%、L∶D=12∶12)研究了斜纹夜蛾取食豇豆Vigna unguiculata、芋艿Colocasia esculenta、烟草Nicotiana tabacum和芥蓝Brassica alboglabra 4种植物对马尼拉侧沟茧蜂的生长发育和繁殖的影响。结果表明:马尼拉侧沟茧蜂寄生取食豇豆的夜蛾幼虫,其幼虫期最短,化蛹率、羽化率和累计存活率最高,性比最低,寿命最长;寄生取食烟草的夜蛾幼虫,其幼虫期最长,化蛹率、羽化率和累计存活率最低,蛹重最轻,蛹期最长;从取食芥蓝的斜纹夜蛾幼虫体内育出的雌蜂产卵量最高,但成蜂寿命最短;斜纹夜蛾取食4种植物对雌蜂个体大小无显著影响,但取食烟草的夜蛾幼虫体内育出的雄蜂个体最小。马尼拉侧沟茧蜂寄生取食不同植物的斜纹夜蛾幼虫,马尼拉侧沟茧蜂的发育和繁殖存在显著差异。     

在受重金属Zn2+胁迫的斜纹夜蛾幼虫寄主上双斑侧沟茧蜂的生存与发育

通过在植食性昆虫斜纹夜蛾Spodoptera litura Fabricius幼虫人工饲料中添加不同浓度的Zn²⁺,测定了连续3代取食含不同Zn²⁺浓度饲料幼虫的血淋巴中Zn²⁺含量,并研究了被Zn²⁺胁迫的斜纹夜蛾幼虫对寄生性天敌双斑侧沟茧蜂Microplitis bicoloratus Chen生存与发育的影响。结果表明,斜纹夜蛾幼虫血淋巴中Zn²⁺含量随饲料中Zn²⁺浓度和幼虫取食世代数的增加而增加;Zn²⁺胁迫斜纹夜蛾幼虫对双斑侧沟茧蜂的寄生率、从寄生到结茧的时间、蛹期长短、成虫羽化率和成虫寿命等都有不同程度的影响,其中以第2代的寄生率和第1代的羽化率受影响最大,均随着Zn²⁺浓度的增大而降低。因此,寄主饲料中高浓度的Zn²⁺能通过食物链影响双斑侧沟茧蜂的生存和发育。     

几种因子对马尼拉侧沟茧蜂寄生效能的影响

马尼拉侧沟茧蜂Microplitis manilae是斜纹夜蛾Spodoptera litura的一种重要幼虫寄生蜂。本文以斜纹夜蛾2龄幼虫为寄主,在26±1℃、RH 65%±5%、L：D=12:12的人工气候箱内,研究生殖方式、雌蜂日龄、寄生时间段、雄蜂出现与否以及雄蜂密度等因子对其寄生效能的影响。结果表明：马尼拉侧沟茧蜂可营产雄孤雌生殖和两性生殖两种生殖方式,两种方式在亲代寄生率、子代羽化率和发育历期均无显著差异。随着雌蜂日龄的增加,其寄生率和子代性比显著降低,但子代发育历期随雌蜂日龄的增加而延长。马尼拉侧沟茧蜂在12:00-18:00时间段的寄生率、子代羽化率和性比最高,子代发育历期最短。当寄生蜂密度一定时,子代性比随着寄主密度的增加而显著增加;当寄主密度一定时,子代性比随着寄生蜂密度的增加而显著下降;雄蜂在场时,子代性比显著高于无雄蜂在场时。子代性比随着亲代雄蜂密度的增加而显著降低,但雄蜂密度对亲代寄生率,子代羽化率、发育历期无显著影响。     

淡足侧沟茧蜂寄生对甜菜夜蛾幼虫血淋巴保护酶和免疫酶的影响

[目的]为探讨淡足侧沟茧蜂Microplitis pallidipes Szepligeti调控寄主甜菜夜蛾Spodoptera exigua(H(u|¨)bner)的生理机制。[方法]测定了淡足侧沟茧蜂寄生甜菜夜蛾后,寄主幼虫血淋巴中保护酶(SOD、CAT及POD)和免疫酶(PO和LSZ)活性的变化。[结果]寄生后连续5 d观察时间内,从寄生后第1天开始,寄主幼虫血淋巴中SOD活性就高于未寄生幼虫(对照),且在寄生后第4~5天达到显著水平;被寄生幼虫血淋巴中CAT活性始终高于对照幼虫,且在寄生后第1、第4~5天达到显著水平;同样,甜菜夜蛾被寄生后,其血淋巴中POD活性明显高于对照幼虫,且在寄生后第1~2、第5天达显著水平;寄生后第1天,寄生与对照组酚氧化酶活性差异不显著,但寄生后第2~5天均达到显著水平;较对照组,寄生后第1~2天,被寄生幼虫溶菌酶活性增加但无显著差异,而寄生后3~4d溶菌酶活性显著降低。[结论]本研究揭示,淡足侧沟茧蜂寄生刺激了甜菜夜蛾幼虫体内的应激反应,诱导寄主体内SOD、CAT和POD活性明显上升,阻止寄生蜂成功寄生;同时,寄生蜂寄生诱导了寄主免疫酶(PO、LSZ)活性的变化,免疫酶活性的变化是寄主免疫系统对寄生蜂寄生的一种应急免疫反应。     

斑痣悬茧蜂在黏虫寄主体内与中红侧沟茧蜂竞争下的存活和发育表现

【目的】不同种寄生蜂在同一小生境中可能寄生同一共享寄主。本研究旨在为认识寄生蜂种间互作关系,并为科学评价寄生性天敌控害效应提供依据。【方法】在室内以单寄生性斑痣悬茧蜂Meteorus pulchricornis(Wesmael)和中红侧沟茧蜂Microplitis mediator(Halidy)及其寄主黏虫Mythimna separata(Walker)低龄幼虫为材料,以寄生顺序和间隔时间为因素进行种间寄生竞争效应实验,观察比较两种蜂的存活和斑痣悬茧蜂子代的发育历期、体型大小和寿命等发育参数。【结果】不同寄生顺序和间隔时间组合处理下斑痣悬茧蜂子代蜂存活率始终高于中红侧沟茧蜂,且先寄生的斑痣悬茧蜂子代存活率高于后寄生的蜂,提前24 h寄生的斑痣悬茧蜂子代存活率可高达96.7%。当斑痣悬茧蜂先于中红侧沟茧蜂寄生时,其子代幼虫发育历期比单独寄生(对照)时显著延长;当后于中红侧沟茧蜂寄生时,其子代幼虫发育历期与单独寄生时无显著差异。各竞争处理下,斑痣悬茧蜂子代成虫寿命均长于单独寄生的子代成虫;子代成虫后足胫节长度与单独寄生相比明显缩短。【结论】结果说明,斑痣悬茧蜂在黏虫低龄幼虫体内与中红侧沟茧蜂的竞争中占有优势,但竞争对斑痣悬茧蜂子代生长发育具有负面影响。     

螟蛉盘绒茧蜂的过寄生行为及其对子代生长发育的影响

【目的】过寄生现象普遍存在于寄生蜂寄生过程中。本研究旨在探究螟蛉盘绒茧蜂Cotesia ruficrus的过寄生对子代发育的影响及影响过寄生行为的主要因素。【方法】室内研究了螟蛉盘绒茧蜂在其寄主稻纵卷叶螟Cnaphalocrocis medinalis3龄幼虫上过寄生行为的发生,不同产卵次数对寄主存活及子代蜂生长发育的影响,研究了不同接蜂时间和不同接蜂密度对过寄生发生的影响。【结果】螟蛉盘绒茧蜂存在过寄生行为,无论雌蜂有无产卵寄生经历,均能在被自身寄生过和同种不同个体寄生过的寄主内产卵。寄生蜂茧量随着被产卵次数的增加而增加,被产卵3~5次的寄主体内死亡的寄生蜂幼虫数随着增大。寄主在育出蜂前的死亡率随着被产卵寄生次数的增加而增加,被产卵5次时,寄主育出蜂前死亡率达50%。过寄生使螟蛉盘绒茧蜂子代蜂卵-蛹的历期延长,羽化率和雌雄性比下降,雌蜂体型随寄生次数的增加显著变小。过寄生率随着接蜂密度及接蜂时间的增加而增加。【结论】在寄主上产卵2次对螟蛉盘绒茧蜂子代发育是最适合的,产卵3次及以上为过寄生。过寄生使蜂子代发育适合度降低,不利于子代生长发育。在室内大量繁殖螟蛉盘绒茧蜂时,应减少接蜂密度和接蜂时间,从而减少过寄生的发生。     

宁波地区斜纹夜蛾幼虫寄生蜂调查研究

2007—2008年的6～11月对宁波地区重要害虫斜纹夜蛾的寄生性天敌进行了调查,发现寄生蜂有18种,主要种类有：马尼拉陡胸茧蜂Snellenius manilae、侧沟茧蜂Microplitis sp、棉铃虫齿唇姬蜂Carnpoletis chlorideae和斑痣悬茧蜂Meteorus pulchricornis,并对主要寄生蜂与斜纹夜蛾幼虫的田间消长动态进行了系统观察。     

淡足侧沟茧蜂寄生对甜菜夜蛾幼虫血淋巴总糖、蛋白质及虫体脂质含量的影响

为探讨淡足侧沟茧蜂Microplitis pallidipes Szepligeti调控寄主的生理机制,测定了淡足侧沟茧蜂寄生后,甜菜夜蛾Spodoptera exigua(Hübner)幼虫血淋巴总糖、蛋白质及虫体脂类含量的变化。研究结果表明,寄生后连续5 d的观察时间内,甜菜夜蛾幼虫血淋巴总糖含量从寄生后第1天开始就高于未寄生寄主幼虫,且在寄生后第2至5天达到显著水平;除寄生后第3天外,被寄生寄主幼虫血淋巴总蛋白质含量始终低于未寄生幼虫,且在寄生后第1、4、5天达到显著水平;甜菜夜蛾被寄生后,虫体脂质含量始终高于未寄生幼虫,且从寄生后第2天开始达到显著水平。本研究揭示,淡足侧沟茧蜂寄生刺激了寄主甜菜夜蛾幼虫血淋巴总糖合成,但抑制了其蛋白质合成,同时也刺激了甜菜夜蛾虫体脂质合成。     

Effect of a nuclear polyhedrosis virus on the relationship between Trichoplusia ni (Lepidoptera: Noctuidae) and the parasite, Hyposoter exiguae (hymenoptera: Ichneumonidae)

The effect of a nuclear polyhedrosis virus on the relationship between Trichoplusia ni and the parasite, Hyposoter exiguae, was investigated to determine if the virus could invade and multiply in the tissues of the parasites, if parasites which emerged from virus-infected T. ni larvae had normal emergence, fecundity, and longevity, and if the parasite could serve as a vector for the virus. Light microscopy revealed particles which appeared to be polyhedra within the lumen of the midgut of parasite larvae from virus-infected hosts. Transmission electron microscopy confirmed the presence of polyhedra and free virions within the midgut of the larvae. Polyhedra or free virions were never found within any parasite tissues. Parasite larvae within hosts exposed to virus before parasitization perished when their hosts died of virus infection. Parasite larvae in hosts exposed to virus after parasitization completed their development before their hosts died of virus infection. The proportion of parasites which survived increased as the time between host parasitization and host virus exposure increased. Parasite larvae which developed in hosts exposed to the virus soon after parasitization spent significantly less time in their hosts than did parasites which developed in noninfected hosts. There was no significant difference in time spent in the pupal stage, percent adult emergence, adult longevity with and without food and water, and fecundity of parasites which developed in virus-infected hosts and those which developed in noninfected hosts. Female parasites laid as many eggs in virus-infected hosts as they did in noninfected hosts. Sixty percent of the female parasites which oviposited in virus-infected hosts vectored infective doses of virus to an average of 6% of the healthy hosts subsequently exposed to them. None of the healthy host larvae exposed to male parasites which had been exposed to virus-infected host larvae became infected with the virus. Forty percent of the female parasites which developed in virus-infected hosts transmitted infective doses of the virus to an average of 65% of the healthy host larvae exposed to them. Ninety percent of the male parasites which developed in virus-infected hosts transferred infective doses of the virus to an average of 21% of the healthy host larvae exposed to them.     

颗粒体病毒、微红绒茧蜂、菜青虫相互关系的初步研究

近几年来,利用颗粒体病毒防治菜粉蝶(Pieris rapae以下称菜青虫)幼虫的工作,在我国已取得了较好的进展(梁东瑞等,1979;河北省菜青虫颗粒体病毒研究协作组,1981)。病毒杀虫剂与化学杀虫剂的显著区别之一,是前者具有选择性,不直接杀伤天敌昆虫。为了明确颗粒体病毒防治菜青虫对寄生蜂种群的影响,以便进一步了解病毒治虫在保持生态平衡上的意义,我们对颗粒体病毒、微红绒茧蜂(Apanteles rubecula)、菜青虫的相互关系作了一些实验室研究,现报道初步结果如后。     

斜纹夜蛾核多角体病流行的时间动态

通过对病病幼虫进行跟踪观察,观察了病毒不同浓度处理下,斜纹夜蛾核多角体病的田间流行动态结果表明,在试验病毒浓度范围（３．１＊１０＾５－３．１＾１０＾８ＰＩＢｓ．ｍｌ＾－１）内,幼虫大多在喷施病毒后第４天开始发病,第５－７天为发病高峰,第５－６天开始病死,第６－天为病死高峰,宿主现患高峰民发病高峰基本一致。宿主种群发病和病死时间分布可用时间－剂量－死亡率模型较好地拟合,模型模拟与实测值有较好的吻合（     

The effect of nucleopolyhedrovirus infection and/or parasitism by Microplitis pallidipes on hemolymph proteins, sugars, and lipids in Spodoptera exigua larvae

We determined the physiological effects of joint and separate nucleopolyhedrovirus (NPV) infection and parasitism by the endoparasitoid Microplitis pallidipes Szepligeti on biochemical events in the noctuid Spodoptera exigua (Hübner). The results indicated that in parasitized larvae, compared to healthy larvae, total protein concentration in host hemolymph began to decline and total sugar concentration significantly increased by the first day, while lipid content in the host body significantly increased by the second day after parasitization. Meanwhile, in jointly infected and parasitized hosts, compared to parasitized larvae, total protein concentration was consistently higher, total sugar concentration was consistently lower, and lipid content became higher by the second day after treatment. In virus-infected larvae, compared to healthy larvae, total protein concentration sharply declined during the first two days but increased by the third, while total sugar concentration increased on the second and third days after virus infection but decreased at other observation times, and lipid content began to increase by the second day after virus infection. Finally, in larvae that were both parasitized and virus-infected, compared to just virus-infected larvae, total protein concentration increased during the first two days but decreased by the third, total sugar concentration increased only on the first and fourth days, and lipid content decreased significantly on the first day but began to increase by the second day after treatment. These findings led us to conclude that parasitization inhibited protein mobilization but stimulated sugar mobilization in host hemolymph, and promoted lipid mobilization in the host body, while Spodoptera exigua NPV infection stimulated protein mobilization induced by parasitization but inhibited sugar mobilization induced by parasitization.     

不同温度下斜纹夜蛾感染核型多角体病毒的流行病模型及模拟

研究了温度对斜纹夜蛾核型多角体病毒病流行的影响.结果表明,温度在29 ℃以上时,感病幼虫大多在2～3 d开始死亡,4～5 d达到高峰.随着温度的升高,感病幼虫病死率增加,病死速度加快.在试验温度范围内,未发现该病毒的热抑制温度,但感病幼虫死亡速率存在恒定温区,在29～35 ℃之间.感病幼虫的每日病死率可用互补重对数模型较好地拟合,累计病死时间分布可用Gompertz模型拟合,生物物理模型经改进后可很好地描述幼虫病死速率与温度的关系,可用于模拟分析不同温度下的幼虫病死时间分布和幼虫病死速率.     

Effect of nucleopolyhedrovirus infection of Spodoptera litura larvae on host discrimination by Microplitis pallidipes

The behaviour and oviposition of solitary endoparasitoid Microplitis pallidipes Szepligeti (Hymenoptera: Braconidae) were monitored to investigate the ability of the parasitoids to distinguish between nucleopolyhedrovirus (NPV)-infected and noninfected Spodoptera litura Fabricius (Lepidoptera: Noctuidae) larvae. The results indicated that the parasitoid searching time and the time until the first parasitoid attack on infected larvae were greater than those recorded on noninfected larvae; the number of infected larvae attacked by parasitoids, the percent of first attacks and parasitism rate in infected larvae were lower than those on noninfected larvae; and these differences were all significant 3 to 5 days postexposure of the larvae to a dose of 1.6 × 10⁸ occlusion bodies (OB)· ml^?1 and significant 4 and 5 days postexposure of the larvae to a dose of 1.6 × 10⁷ OB·ml^?1. The lowest dosage (1.6 × 10⁶ OB·ml^?1) had no significant effect on the above index values. In a field cage experiment, we found that the percentage of infected larvae parasitized by M. pallidipes gradually decreased as the time after NPV inoculation (1.6 × 10⁸ OB·ml^?1) increased, and that M. pallidipes significantly preferred to oviposit in healthy larvae from day 3 to day 5 after virus inoculation. Our research concluded that this parasitoid's ability to discriminate between healthy and infected hosts increased as virus concentration increased and as the time between exposure of hosts to virus and subsequent exposure to parasitoids increased.     

斑痣悬茧蜂寄生、发育和生殖特征与寄主幼虫日龄的关系

【目的】“圆屋顶形”假说认为,对单寄生性姬蜂和茧蜂适合度而言,中间龄期幼虫寄主的品质高于更早和更晚龄期幼虫。该假说得到许多研究支持,但这些研究常以寄主幼虫脱皮划分虫龄,很少观测生殖特征,从而难以确切和全面描述适合度随寄主生长发育变化而变化的关系。本研究旨在检验“圆屋顶形”假说。【方法】本研究以斜纹夜蛾Spodoptera litura不同日龄幼虫为寄主,观测斑痣悬茧蜂Meteorus pulchricornis寄生和发育特征,并测定成蜂生殖力。【结果】线性回归分析表明,雌蜂对中间日龄寄主幼虫的寄生率大于对两端日龄寄主幼虫的寄生率;蜂卵至成虫的存活、成虫体型大小及其生殖力（产卵量）等适合度相关特征均表现出中间日龄寄主幼虫处理大于两端日龄幼虫处理。【结论】研究结果支持“圆屋顶形”假说。     

莱氏绿僵菌对斜纹夜蛾的致病力及生理效应

【目的】测定莱氏绿僵菌Metarhizium rileyi Nr5772菌株对斜纹夜蛾Spodoptera litura幼虫及蛹的致病能力,研究莱氏绿僵菌侵染后在寄主体内的发育及对寄主的生理效应,探讨莱氏绿僵菌的致病机制。【方法】采用浸渍法测定莱氏绿僵菌孢子对斜纹夜蛾3-6龄幼虫及蛹的致死中浓度(LC_(50))和致死中时(LT_(50))。采用微量注射法接种莱氏绿僵菌虫菌体,在不同时间后采集斜纹夜蛾幼虫血淋巴,在显微镜下检查虫菌体的数量、形态及寄主血细胞数量,并用酶标仪测定寄主血淋巴酚氧化酶(Phenoloxidase,PO)的活性。【结果】M.rileyi孢子对3龄斜纹夜蛾幼虫毒力最强,10 d后LC_(50)=3.12×10~6个孢子/mL,龄期越大,致病力越低;孢子浓度为5×10~9个/mL时,对3龄幼虫的致死速度最快,LT_(50)=4.55 d,致死速度随龄期的增大和浓度的降低逐渐减缓;M.rileyi孢子对蛹的致病力远低于对幼虫的致病力。注射接种虫菌体后,64 h内,虫菌体数量在寄主血腔中以幂函数的形式增长,寄主的血细胞数量没有明显的变化;在侵染初期(接种后44 h内),血淋巴PO活性正常;在侵染后期,虫菌体数量不再增加(55-64 h后),逐渐转化为菌丝体,并快速杀死寄主,PO活性受到抑制。【结论】莱氏绿僵菌Nr5772菌株对斜纹夜蛾幼虫有较强的致病力,应在害虫低龄期应用;莱氏绿僵菌在侵染初期对寄主血细胞和血淋巴PO无影响,后期则完全抑制PO活性。