快速评价内寄生蜂雌蜂携带因子生理活性的简易方法

介绍一种以γ-射线辐射处理雌蜂,评价内寄生蜂雌蜂携带因子生理活性的简易方法。该方法既能维持雌蜂正常的寄生能力和携带因子的生理活性,又能排除寄生蜂胚胎和幼虫来源因子对寄主的影响。当以150Gy剂量的γ-射线处理蝶蛹金小蜂雌蜂时,其存活率和产卵能力未受明显影响,但其子代胚胎不能发育。经辐射处理的雌蜂寄生菜粉蝶蛹后能象未处理正常蜂一样明显地抑制寄主的血细胞免疫,其引起寄主血细胞总数、组成、死亡率及浆血细胞延展率变化与正常蜂基本一致。结果表明,寄主蛹被寄生后其血细胞免疫受抑制主要是该蜂雌蜂携带因子引起的。最后讨论了使用该方法的注意事项。     

小菜蛾内寄生蜂——菜蛾盘绒茧蜂的种内竞争

在室内(25±1)℃,以小菜蛾3龄幼虫为初始寄主,对过寄生后,小菜蛾幼虫内寄生蜂——菜蛾盘绒茧蜂的种内竞争进行了研究。当2头雌蜂同时寄生(10 min内)同一头寄主,2 d后几乎同时孵化的茧蜂幼虫总有一头1龄幼虫利用发达的角质化上颚攻击同类竞争者。当两次寄生间隔时间为24、48和72 h时,先寄生的茧蜂幼虫分别以86.7%,95.0%和96.9%的比例在发育中占据优势,1龄幼虫使用上颚将后孵化的初孵幼虫杀死,或直接攻击蜂卵致使包囊、黑化的发生,此时物理攻击发挥主要作用,并可能通过先寄生者释放畸形细胞、水解酶等生理抑制方式完全阻碍后产入的蜂卵的发育。当两次寄生间隔时间长达96或120 h,因寄主已不适合茧蜂的再次产卵寄生,致使过寄生率由100%分别下降为69.4%和60.7%;已发生过寄生的个体中,80.0%以上以先寄生者吐丝、结茧化蛹,后寄生者则伴随被过寄生寄主的死亡而不能完成发育。以上结果表明,当种内竞争发生时,菜蛾盘绒茧蜂可通过物理攻击和生理抑制两种途径排除同类竞争者,竞争结果主要取决于雌蜂2次寄生的先后顺序。     

小菜蛾内寄生蜂--菜蛾盘绒茧蜂的种内竞争

在室内（25±1）℃,以小菜蛾3龄幼虫为初始寄主,对过寄生后,小菜蛾幼虫内寄生蜂--菜蛾盘绒茧蜂的种内竞争进行了研究。当2头雌蜂同时寄生（10 min内）同一头寄主,2 d后几乎同时孵化的茧蜂幼虫总有一头1龄幼虫利用发达的角质化上颚攻击同类竞争者。当两次寄生间隔时间为24、48和72 h时,先寄生的茧蜂幼虫分别以86.7%,95.0%和96.9%的比例在发育中占据优势,1龄幼虫使用上颚将后孵化的初孵幼虫杀死,或直接攻击蜂卵致使包囊、黑化的发生,此时物理攻击发挥主要作用,并可能通过先寄生者释放畸形细胞、水解酶等生理抑制方式完全阻碍后产入的蜂卵的发育。当两次寄生间隔时间长达96或120 h,因寄主已不适合茧蜂的再次产卵寄生,致使过寄生率由100%分别下降为69.4%和60.7%;已发生过寄生的个体中,80.0%以上以先寄生者吐丝、结茧化蛹,后寄生者则伴随被过寄生寄主的死亡而不能完成发育。以上结果表明,当种内竞争发生时,菜蛾盘绒茧蜂可通过物理攻击和生理抑制两种途径排除同类竞争者,竞争结果主要取决于雌蜂2次寄生的先后顺序。     

不同寄主对花绒寄甲生长发育和耐寒性的影响

为了探讨寄生不同寄主对花绒寄甲Dastarcus helophoroides（Fairmaire）生长发育和耐寒性的影响，于室内分别用鞘翅目的Zophobas morio蛹、麻竖毛天牛Thyestilla gebleri和松褐天牛Monochamus alternatus Hope的幼虫作为寄主，统计和分析花绒寄甲的发育历期、成虫产出数、成虫个体大小和过冷却点。结果发现：寄生不同寄主对花绒寄甲的成虫产出数无显著影响，但对其幼虫历期、蛹历期、成虫体长、成虫体重和过冷却点有显著影响。寄生Zophobas morio蛹的花绒寄甲幼虫历期（10.58 d）和蛹历期（30.17 d）均最长，成虫体长最长（8.68 mm），体重最重（360.22 mg），过冷却点最低（-18.81℃）；而寄生麻竖毛天牛幼虫的花绒寄甲幼虫历期（8.94 d）和蛹历期（22.84 d）均最短，成虫体长最短（6.33 mm），体重最轻（184.38 mg），过冷却点最高（-16.50℃）。相比麻竖毛天牛和松褐天牛的幼虫，Zophobas morio蛹所繁育的花绒寄甲成虫体型更大且耐寒性更强，Zophobas morio蛹是繁育更为健壮和耐寒的花绒寄甲种群的理想替代寄主。     

菜蛾啮小蜂对寄主龄期的选择性和适合性

菜蛾啮小蜂是小菜蛾幼虫期至蛹期的跨期寄生蜂,也可仅寄生于蛹。室内寄主虫态及龄期选择寄生试验表明,该蜂嗜好产卵寄生幼虫,较少产卵寄生预蛹,很少产卵寄生蛹,但在幼虫４个龄期间无明显偏嗜性。寄生于各龄小菜蛾幼虫的啮小蜂在发育历期、蛹期存活率、每寄主育出蜂数及性比几方面无显著差异,表明各龄幼虫对该蜂的适合性基本一致     

菜蛾啮小峰对寄主龄期的选择性和适合性

菜蛾啮小蜂是小菜蛾幼虫期至蛹期的跨期寄生蜂,也可仅寄生于蛹。室内寄主虫态及龄期选择寄生试验表明,该蜂嗜好产卵寄生幼虫。较少产卵寄生预蛹,很少产卵寄生蛹,但在幼虫４个龄期间无明显偏嗜性,寄生于各龄小菜蛾幼虫的啮小蜂在发育历期,蛹期存活率,每寄主育出蜂数及性比几方面无显著差异,表明各龄幼虫对该蜂的适合性基本一致。     

斑痣悬茧蜂对受药寄主幼虫的选择性及其后代表现

为探究受到杀虫剂亚致死影响的寄主幼虫对寄生蜂的寄主选择及其子代蜂的影响,以容性寄生蜂斑痣悬茧蜂Meteorus pulchricornis为研究对象,以氯氰菊酯亚致死浓度处理的甜菜夜蛾Spodoptera exigua4龄幼虫为寄主幼虫,进行非选择性和选择性试验。非选择性试验表明,斑痣悬茧蜂成功寄生（完成化蛹）的概率随受药寄主的体重增大而提高,而且受药寄主有效存活的概率亦随其体重增大而提高;与对照寄主相比,寄生蜂对受药寄主的寄生率降低60.2%、子代蜂发育历期显著延长、子代蜂体型（用后足胫节长度表示）显著增大。与来自对照寄主的子代蜂相比,来自受药寄主的子代蜂的寄生能力（用寄生率表示）未受影响,但其后代的结茧率降低10%、发育历期显著缩短、体型显著增大,说明羽化蜂的发育适合度得到了提高。选择性试验结果得出不一致的结论,根据对寄生蜂攻击次数的分析,未发现其在对照与受药寄主之间存在显著偏好;但根据第2次攻击的寄主识别期变量进行的风险分析,受药寄主被寄生风险显著低于对照寄主（低59.7%）,说明寄生蜂偏好攻击对照寄主幼虫。研究结果说明,斑痣悬茧蜂通过偏好体型较大的寄主幼虫,而减轻了受到杀虫剂亚致死效应的间接不良影响。结果表明该寄生蜂具有鉴别出接受亚致死杀虫剂不久的寄主幼虫的能力。     

寄主大小棉铃虫齿唇姬蜂产卵和发育的关系

以在27℃下、室内人工饲养的棉铃早和棉铃早齿蜃 为材料，研究了寄主大小对棉铃虫齿唇姬蜂产卵和生长发育的影响。结果表明，寄主大小对雌蜂产卵有显著的影响。寄生率随寄主体重增加而降低，在被寄生产卵的棉铃虫幼虫中，体重小于18mg的占92％，大于18mg的幼虫不适宜该寄生蜂产卵；人工饲料上饲养的棉铃虫幼虫，自孵化后的136h为适合被寄生的时段，对数据的相关和回归分析表明，寄主寄生时体重与蜂近似幼虫体重、蜂近似幼虫体重与成蜂体重均呈显著的正相关，尤其在雌蜂上表现得更为显著；成蜂在一定的范围内，体重越大，寿命越长，体重过大或过小，寿命均有下降的趋势，寄主大小对的发育历期无显著影响。     

双斑截尾寄蝇对草地螟寄生的主要生物学特征及饲养技术

首次报道了双斑截尾寄蝇(Nemorilla maculosa Meigen)对草地螟(Loxostege sticticalis L.)的寄生行为及发育特征和饲养技术。研究结果表明:双斑截尾寄蝇将卵产在5龄草地螟幼虫的胸部,蝇蛆孵化后直接钻入寄主体腔内发育,幼虫发育成熟后便会钻出寄主体外化蛹。完成卵到幼虫期的发育需约12 d。蛹经11 d左右即可以羽化为成虫。从卵到成虫的发育历期约25 d。雌雄之间卵和幼虫的发育历期没有显著差异,但雌蛹的发育比雄蛹慢。雌蝇羽化后可以立即交配,而雄蝇羽化后约2 d后才能交配。补充营养的雌蝇平均产卵量约为130粒/头。还初步研究了影响双斑截尾寄蝇寄生能力的因素。简单介绍了其室内饲养繁殖技术。     

甜菜夜蛾核多角体病毒对斑痣悬茧蜂发育及存活的影响

研究了甜菜夜蛾核多角体病毒对斑痣悬茧蜂Meteorus pulchricornis发育及存活的影响。正在蜕皮的甜菜夜蛾Spodoptera exigua 2龄幼虫被斑痣悬茧蜂寄生后,当其发育到3龄与4龄时分别饲以95%致死浓度(LC_(95))或10×LC_(95)甜菜夜蛾核多角体病毒(SpeiNPV),研究表明:甜菜夜蛾核多角体病毒对斑痣悬茧蜂发育及存活产生不利的影响,影响程度取决于寄生与饲毒的间隔期以及饲毒量。被寄生的甜菜夜蛾幼虫发育到第3龄(即被寄生后第1天,1dpp)分别饲以LC_(95)或10×LC_(95) SpeiNPV的处理,没有寄生蜂老熟幼虫从寄主体内钻出;被寄生的甜菜夜蛾幼虫发育到第4龄(4 dpp)分别饲以LC_(95)或10×LC_(95) SpeiNPV的处理,分别有25.62%与16.31%寄生蜂老熟幼虫从寄主体内钻出。甜菜夜蛾是否饲毒对寄生蜂的出蜂率、化蛹率及羽化率影响显著;饲毒浓度影响寄生蜂的出蜂率、化蛹率,但不影响羽化率。甜菜夜蛾饲毒与否对寄生蜂幼虫及蛹的发育历期无显著影响,但饲毒甜菜夜蛾体内寄生蜂幼虫、蛹及成蜂显著小于未饲毒的甜菜夜蛾体内寄生蜂幼虫、蛹及成蜂。     

Parasitization by Cotesia plutellae enhances detoxifying enzyme activity in Plutella xylostella

Insecticidal tests using diazinon showed that the mortality of Plutella xylostella larvae parasitized by Cotesia plutellae was reduced by 4.6-fold compared to that of the nonparasitized hosts. The use of chemicals with synergistic effect to insecticides in toxicity assay helps to elucidate the kind of enzyme involved in lowering insect mortality. Synergism of diethyl maleate and piperonyl butoxide with diazinon resulted to 2.4- and 1.9-fold increase, respectively, in susceptibility of parasitized larvae compared to those of nonparasitized larvae. These results indicated the possibility that the decrease in susceptibility to diazinon was due to the elevated activities of glutathione-S-transferase (GST) and cytochrome P450 monooxygenase (CYP), respectively. The GST activities in parasitized larvae were significantly higher than those of nonparasitized ones starting from three days post-parasitization until emergence of parasitoid larva. High GST activities during late parasitism could be attributed to both enzyme activities toward diazinon of parasitized P. xylostella larva itself and C. plutellae larva inside larval host. High GST activity one day after parasitization, although statistical significance was not detected, was caused by polydnavirus (PDV) and the venom of C. plutellae not by parasitoid larvae. Artificial injection of PDV plus venom demonstrated that the resulting increase in GST activity is similar to the increase brought by parasitization. High CYP activity after 3 days post-parasitization in parasitized larva was attributed mainly to the activity of parasitoid larva. Carboxylesterase activity in the parasitized host remained at a high level, while that in the nonparasitized host decreased slightly as pupation approaches. On the other hand, acetylcholinesterase activity also remained constant after parasitization until larval emergence, while that of the nonparasitized hosts decreased gradually as the host larvae approach pupation. These results were supported by inhibition tests using diazoxon in vitro.     

菜蛾绒茧蜂的寄主选择性及寄生对寄主发育和取食的影响

研究了菜蛾绒茧寄生对寄主幼虫龄期的选择性及对寄主生长发育、取食量的影响。结果表明,该蜂能寄生小菜蛾各个龄期的幼虫,但当２－４龄幼虫同时存在时,偏爱寄生２、３龄幼虫,对２、３、４龄幼虫的选择系数分别为０．３７、０．３９、０．２４。该蜂对４龄幼虫的寄生能力随寄主日龄增大而急剧下降,对进入４龄并发育至该龄期４０％时间以上的幼虫不能寄生。产卵寄生的雌蜂比例也随４龄幼虫日龄增大而急剧下降。小菜蛾幼虫被寄主后     

丽蚜小蜂寄生对Q型烟粉虱生长发育的影响

为明确丽蚜小蜂寄生对Q型烟粉虱的影响,通过室内饲养观察不同龄期Q型烟粉虱被丽蚜小蜂寄生后的生长发育,并比较了被寄生后烟粉虱若虫的个体大小及死亡率。结果表明,2龄、3龄和4龄烟粉虱若虫被寄生后均能继续发育,2龄若虫蜕皮进入3龄和3龄若虫蜕皮进入4龄的时间与对照间无显著差异,而被寄生若虫的4龄期显著延长。对于同一龄期的烟粉虱若虫,丽蚜小蜂偏向于选择较大的个体寄生,2龄和3龄被寄生若虫发育后期个体比未被寄生个体大,但4龄时被寄生的个体在发育后期略小于未被寄生个体,显示丽蚜小蜂对不同龄期若虫的生长发育影响不同。2龄若虫死亡率为61.64%,显著高于3龄和4龄若虫;4龄若虫褐蛹率最高,为48.84%。表明无论寄生哪一发育阶段的烟粉虱若虫,丽蚜小蜂的寄生均为容性寄生,田间应用丽蚜小蜂防治Q型烟粉虱时在其若虫3~4龄时释放更适宜。     

寄生蜂畸形细胞特性及与蜂幼虫生长发育的关系

本文综述寄生蜂畸形细胞特性及其功能研究的最新进展。一些进化高等的膜翅目内寄生蜂,在胚胎发育过程中,包裹在胚胎周围的浆膜会随着蜂卵的孵化,以游离的细胞团或单个细胞的形式释放到寄主昆虫的血淋巴中。这些源自浆膜被称作畸形细胞(Teratocyte)的特殊类群,在伴随蜂幼虫的生长发育过程中,自身也经历一系列结构和功能的改变。它们主要通过分泌蛋白质或酶类,改变寄主的物质代谢途径等方式为发育中的蜂幼虫提供营养和能量。对寄生蜂重要的调控因子-畸形细胞的特性及与蜂幼虫相互关系的揭示,可以阐明寄生蜂-寄主昆虫协同进化的内在机理,也可为开发害虫生物防治新策略提供新的思路和途径。     

半闭弯尾姬蜂的寄主选择性及寄生对寄主发育和取食的影响

在24℃下研究了半闭弯尾姬蜂寄生对寄主幼虫龄期的选择性及对寄主生长发育、取食量的影响。结果表明，该蜂能寄生小菜蛾2-4龄的幼虫，但当2-4龄幼虫同时存在时，偏爱寄生2、3龄幼虫，对2、3、4龄幼虫的选择系数分别为0．37、0．44、0．19。该蜂对4龄幼虫的寄生能力随寄主日龄增大而下降。2-4龄小菜蛾幼虫被寄生后，总发育历期与预蛹期都比未被寄生的显著延长。当小菜蛾幼虫在2龄初被寄生后，总取食量比未被寄生的显著减少；但当幼虫在3、4龄初被寄生后，各龄的取食量与未被寄生的差异不显著。     

管侧沟茧蜂寄生对粘虫在玉米植株上分布位置选择性的影响

为明确管侧沟茧蜂Microplitis tuberculifer寄生对粘虫Mythimna separata在玉米植株上分布位置的影响及相关机理,采用生物学观察法在温室和实验室内监测了被寄生与未被寄生的粘虫幼虫在玉米活体植株和离体叶片上的分布及管侧沟茧蜂结茧位置的变化。结果表明,被管侧沟茧蜂寄生的粘虫幼虫在玉米叶片背面的平均分布比例为36.29%,显著高于未被寄生粘虫的14.60%;寄生后第8天开始,被寄生粘虫在黄色叶片上的分布比例显著高于未被寄生粘虫;非滞育和滞育条件下,管侧沟茧蜂在玉米植株黄色叶片上的平均结茧数目分别为19.3个和15.3个,显著高于绿叶上的6.5个和4.7个及土面上的0.8个和0.7个,选择性试验发现湿度在结茧位置的选择中发挥着重要作用。研究表明,管侧沟茧蜂可以通过调控寄主粘虫在玉米植株上的分布位置协助其找到合适的结茧位置。     

Impact of neem and chinaberry fruit extracts on the pest/parasitoid (Pieris rapae/Hyposoter ebeninus) interactions

A new technique was performed to simulate exposure of the host Pieris rapae larvae to both botanical treatment and the parasitoid Hyposoter eheninus in different sequences. It was found that: host larvae subjected to both parasitoid and 1% neem treatment showed significant or insignificant reductions both in pupal formation as well as adult emergence percentages when treatment preceded or followed parasitism, respectively. Both neem treatments revealed significant prolongation in the development of unparasitized and parasitized larvae (on average 4 to 5 days delay), whereas chinaberry caused significant prolongation only among parasitized larvae (on average 2.7 days delay in egg-larval duration). Fate of parasitism among untreated hosts was found to be faster than among neem-treated ones. Parasitism percentages among 1 and 0.5% neem-treated third instar host larvae held 7 days before parasitism reached 3 and 2 times that achieved among those reared on untreated diet for the same period, ­respectively.It was concluded that prolongation of the preferred target instars of the host, due to neem treatments, increased the chance for parasitism. Nevertheless, treatment with neem at the LC₅₀ level exhibited a great reduction in parasitoid progeny. However, a lower concentration (LC₂₅) could reasonably potentiate parasitism without drastic losses in parasitoid emergence.     

Impact of neem and chinaberry fruit extracts on the pest/parasitoid (Pieris rapae/Hyposoter ebeninus) interactions

A new technique was performed to simulate exposure of the host Pieris rapae larvae to both botanical treatment and the parasitoid Hyposoter eheninus in different sequences. It was found that: host larvae subjected to both parasitoid and 1% neem treatment showed significant or insignificant reductions both in pupal formation as well as adult emergence percentages when treatment preceded or followed parasitism, respectively. Both neem treatments revealed significant prolongation in the development of unparasitized and parasitized larvae (on average 4 to 5 days delay), whereas chinaberry caused significant prolongation only among parasitized larvae (on average 2.7 days delay in egg-larval duration). Fate of parasitism among untreated hosts was found to be faster than among neem-treated ones. Parasitism percentages among 1 and 0.5% neem-treated third instar host larvae held 7 days before parasitism reached 3 and 2 times that achieved among those reared on untreated diet for the same period, ­respectively.It was concluded that prolongation of the preferred target instars of the host, due to neem treatments, increased the chance for parasitism. Nevertheless, treatment with neem at the LC₅₀ level exhibited a great reduction in parasitoid progeny. However, a lower concentration (LC₂₅) could reasonably potentiate parasitism without drastic losses in parasitoid emergence.     

短梳角野螟寄生蜂-螟蛉绒茧蜂的生物学特性

螟蛉绒茧蜂是寄生红花天料木(母生)主要害虫短梳角野螟的寄生性天敌昆虫。本文针对该寄生蜂开展其生物学、发育及寄生特性研究,采用室内测定结合林间调查的方法,系统调查及研究螟蛉绒茧蜂的生物学特性。结果显示:实验室条件下,螟蛉绒茧蜂单雌寄生数量为9~24头,平均寄生20头;偏好寄生3、4龄短梳角野螟幼虫,很少寄生低龄幼虫,不寄生5龄幼虫;当寄生低龄幼虫且完成其发育时,羽化的成蜂都为雄蜂;当短梳角野螟2龄、3龄初、3龄末和4龄幼虫同时存在时,喜寄生3龄初幼虫,偏好系数为0.574 3;试验条件下寄生蜂的发育历期和个体大小随着寄主龄期的增大有所增长,相同温度下补充外源营养均可延长成蜂寿命。研究结果可为利用螟蛉绒茧蜂防控短梳角野螟的林间应用提供参考。     

二化螟盘绒茧蜂寄生对寄主二化螟幼虫免疫反应的影响

为了探明二化螟盘绒茧蜂Cotesia chilonis (Matsumura)寄生对寄主二化螟Chilo suppressalis (Walker)幼虫血细胞和体液免疫反应的影响,观察并测定了二化螟盘绒茧蜂寄生引起二化螟幼虫血细胞数量、延展、存活、吞噬和包囊作用以及血淋巴酚氧化酶活性等的变化。结果显示,二化螟幼虫血细胞总数在寄生后1天即显著高于对照。其中,颗粒血细胞和浆血细胞在寄生后的数量变化均与血细胞总数变化相似,颗粒血细胞在寄生后3天、浆血细胞在寄生后0.5天起即分别与其对照差异显著,但两种血细胞在血细胞总数中各自所占的比例与对照多无显著差异。二化螟幼虫血细胞延展能力在寄生后0.5天受到显著抑制,此后与对照无显著差异;同时寄生可增加寄主血细胞的死亡率。寄主幼虫血细胞的吞噬作用在寄生后2天起显著降低;包囊作用则在寄生后1天起显著降低。二化螟幼虫被二化螟盘绒茧蜂寄生后,血淋巴酚氧化酶活性显著升高,但随后呈逐渐下降趋势。研究结果说明,二化螟盘绒茧蜂寄生使寄主二化螟幼虫的免疫反应呈现一定的规律变化。