木瓜实蝇对七种寄主果实的选择性

木瓜实蝇属于我国进境检疫性害虫。为明确该虫对不同寄主果实的选择性,以评价其危害风险,本研究选择橙子、苹果、番石榴、杨桃、木瓜、西红柿、辣椒7种果实作为供试寄主,在室内选择性条件下比较了木瓜实蝇在不同寄主上的产卵量和幼虫发育的适合性。结果表明,以寄主气味诱导产卵器采卵时,雌虫在番石榴、橙子上产卵量明显高于其它所有供试寄主;以果实直接诱导产卵时,则以番石榴饲养出的幼虫数最多,而在橙子、西红柿上的幼虫数为0。在非选择性条件下将幼虫接入果实供试,表明木瓜实蝇幼虫在不同供试寄主上的存活率(化蛹率)均较高,最高为木瓜和杨桃,分别为92.0%和91.3%,最低为苹果,达到66.0%。不同供试果实对木瓜实蝇幼虫的发育历期、存活率(化蛹率)和蛹重有显著影响,但各适合性指标在不同寄主间的变化趋势不一致。上述结果表明,寄主气味及果皮特征对成虫的产卵选择性具有明显的影响,以产卵选择性和幼虫发育为综合指标,认为木瓜实蝇对番石榴的选择性最高。     

6种寄主果实对南瓜实蝇和瓜实蝇产卵选择 及其子代发育的影响

为探讨南瓜实蝇和瓜实蝇对不同寄主的产卵选择性及其与子代生长发育的关联度,采用生态测定方法,研究2种实蝇对南瓜、黄瓜、姜柄瓜、西葫芦、丝瓜和苦瓜6种寄主果实的产卵选择以及幼虫取食6种寄主后对其生长发育的影响。在产卵选择性试验中,2种实蝇对6种寄主的产卵选择性较为一致,均偏向于在丝瓜和黄瓜上产卵。在非产卵选择性试验中,南瓜实蝇在黄瓜和姜柄瓜上的产卵量较多;瓜实蝇在丝瓜和姜柄瓜上的产卵量较多;2种实蝇都对姜柄瓜有一定的偏好。在气味诱导的产卵选择性试验中,南瓜实蝇在姜柄瓜和黄瓜上的产卵量较多;瓜实蝇在黄瓜和丝瓜上的产卵量较多;2种实蝇都对黄瓜气味有一定的偏好;且南瓜实蝇和瓜实蝇都不偏好在苦瓜上产卵。南瓜实蝇分别取食黄瓜、苦瓜时,其幼虫期、蛹期较短;取食姜柄瓜时,蛹重最大;分别取食南瓜和黄瓜时的化蛹率、羽化率最高。瓜实蝇取食西葫芦时,幼虫期较短;取食丝瓜时,蛹期较短,且蛹重最大;分别取食黄瓜和南瓜时的化蛹率、羽化率最高。南瓜实蝇和瓜实蝇对不同寄主果实的产卵选择性均存在明显差异,寄主外部物理性状对实蝇的产卵选择有显著影响,2种实蝇对6种寄主果实产卵选择性和幼虫生长发育适应性的相关性不显著。     

番石榴实蝇寄主选择性试验

番石榴实蝇Bactrocera correcta(Bezzi)是一种为害多种水果的害虫,近年来在云南的元江暴发成灾。本试验选择番石榴实蝇的常见寄主:梨、芒果、苹果、桃、橙及芒果的不同品种进行室内试验,比较番石榴实蝇雌虫产卵对寄主的选择性及不同寄主对番石榴实蝇生长发育的影响。结果显示,番石榴实蝇雌虫对5种供试水果的寄生选择性大小依次为桃>梨>芒果>橙>苹果;番石榴实蝇对芒果不同品种的寄生选择性为三年芒>台农行1号>虎豹牙>胭脂芒>鹰嘴芒;番石榴实蝇在不同寄主上的蛀果期(卵及幼虫的历期)具有极显著的差异,以寄生桃和芒果的最短;从梨和苹果上饲养出的蛹最轻,且极显著低于其它寄主上饲养出来的蛹重;苹果上寄生的番石榴实蝇蛹重与蛀果期呈显著的正相关,而寄生梨的番石榴实蝇蛹重与蛀果期呈极显著的负相关。结果表明,番石榴实蝇雌虫产卵对不同寄主或同一寄主不同品种有明显的选择性,且该选择行为与其后代的生长发育有关。     

植食性昆虫寄主植物嗅觉搜寻述介

植食性昆虫与寄主植物关系的本质是化学。植食性昆虫搜寻寄主的嗅觉媒介是植物气味即化学信息物质。在介绍植物气味构成及其扩散模型基础上，阐述了植物气味在地上植食性昆虫成虫、幼虫和地下植食性昆虫搜寻寄主过程中的嗅觉导向作用，并指出了今后相关研究需要注意的问题。从植物与环境因子的关系来看，植物气味包括构成性气味和诱发性气味两类，这两类气味的概念既相联系而又不同。构成性气味组分及构成因植物分类地位等而不同。诱发性气味组分因植食性昆虫取食、植物病原微生物、机械致伤等因子的胁迫而变化，这种变化性状随植物属和/或种、植株生长发育阶段、胁迫因子性质及其作用方式而不同。无论是哪种植物气味，其释放均具有节律性。气味扩散过程比较复杂，扩散状态可用数学模型表征。对于地上植食性昆虫成虫，植物气味对其寄主搜寻行为具有导向特异性，重点分析了这种特异性形成的两个假说；鳞翅目昆虫幼虫，能够利用植物化学信息物质趋向寄主植物或回避非寄主植物；地下植食性昆虫搜寻寄主，既与寄主植物地下组织释放或分泌的次级代谢物有关，又与一些初级代谢物有关。初级代谢物中的CO₂,起着“搜寻触发器”作用。有助于增强人们对昆虫与植...     

橘小实蝇和番石榴实蝇重复利用寄主的产卵选择性

检疫性害虫橘小实蝇Bactrocera dorsalis和番石榴实蝇Bactrocera correcta是近缘种。本研究显示,两种实蝇对已被产卵寄主的识别与产卵选择性极相似。当寄主中至少含有600粒新鲜卵时,橘小实蝇或番石榴实蝇的雌成虫在其上继续产卵的数量才被抑制,而对同种实蝇卵和异种实蝇卵的反应几乎没有差异;两种实蝇在已被产卵的寄主中再次产卵,并没有刻意回避原产卵孔;寄主中的卵孵化为幼虫对后续实蝇的产卵行为产生了显著的抑制作用,随着幼虫数量的增多与龄期的增长,便不再有雌蝇选择该寄主产卵。因此,寄主中幼虫的存在是驱避橘小实蝇和番石榴实蝇在其上继续产卵的重要因素。两种实蝇幼虫寄主标记信息素的鉴定与利用将是今后研究的重点,利用其进行有害实蝇的种群控制将有很大的应用前景。     

草地贪夜蛾对5种寄主植物和6种杂草的取食选择性和适应性

为明确草地贪夜蛾Spodoptera frugiperda J. E. Smith对不同寄主植物和主要杂草的取食选择及适应性,以玉米Zea mays、甘蔗Saccharum officinarum、花生Arachis hypogaea、大豆Glycine max、香蕉Musa nana、稗草Echinochloa crusgalli、马唐Digitaria sanguinalis、牛筋草Eleusine indica、莎草Cyperus rotundus、马齿苋Portulaca oleracea、鹅肠草Malachium aquaticum作为寄主,采用叶碟法测定草地贪夜蛾各龄幼虫对5种寄主植物和6种杂草的取食偏好,并测定了不同虫态的发育历期、单头蛹重、化蛹率以及单雌产卵量等。结果表明,草地贪夜蛾在5种寄主植物和6种杂草上均可完成世代发育。寄主作物中,香蕉处理的草地贪夜蛾成虫前期最长,为29.66 d;甘蔗处理下草地贪夜蛾蛹重和化蛹率分别为250.44 mg和71.67%,显著低于玉米和花生处理的蛹重和化蛹率;草地贪夜蛾取食花生后单雌产卵量最高,为768.93粒,与玉米上产卵量差异不显著,香蕉上最低,为498.76粒;1~2龄幼虫对玉米和香蕉的取食选择率有显著差异,3~6龄幼虫对玉米取食选择率显著高于其他寄主植物。6种杂草中取食莎草的成虫前期最长30.21 d,且单雌产卵量最低526.33粒;取食鹅肠草蛹重最低188.00 mg;取食马齿苋化蛹率最低为72.37%;草地贪夜蛾取食马唐后其蛹重、化蛹率、单雌产卵量最高,与取食其它5种杂草有显著性差异;2~4龄幼虫更偏向取食马唐,与其它5种差异显著。研究结果表明：寄主植物种类对草地贪夜蛾的生长发育有显著影响,其中草地贪夜蛾对玉米和马唐具有较高的取食偏好。     

草地贪夜蛾对2种豆科蔬菜的取食和产卵选择性及其适应性研究

草地贪夜蛾Spodoptera frugiperda是一种多食性昆虫,为明确该害虫对不同寄主的选择性和适生性,本文比较了草地贪夜蛾对玉米Zea mays、豇豆Vigna unguiculata和四季豆Phaseolus vulgaris等3种寄主的取食及产卵偏好性,并分析了取食不同寄主对其生长发育及繁殖的影响。结果表明：草地贪夜蛾低龄幼虫（初孵幼虫和2龄）对玉米叶和豇豆叶表现出取食偏好性,而高龄幼虫（3龄和5龄）对3种寄主不同组织的取食选择性无明显差异;草地贪夜蛾取食3种寄主植物均可以完成世代发育,但取食豇豆叶和四季豆叶的幼虫历期、蛹历期显著变短,化蛹率、羽化率显著降低;取食豇豆叶对其蛹重、成虫寿命无显著影响,但取食四季豆叶的蛹重显著变轻、雄成虫寿命显著变短;种群生命表参数显示,草地贪夜蛾在3种寄主上的繁殖力表现为玉米叶（1 138.29）>豇豆叶（1 179.00）>四季豆叶（585.50）,处理间差异显著;取食2种非嗜好寄主的种群内禀增长率（rm）和周限增长率（λ）均显著降低,平均世代历期（T）显著延长,取食豇豆叶的雌雄性比显著降低;草地贪夜蛾对寄主玉米具有明显的产卵偏好性,选择豇豆和四季豆的产卵量仅占植物着卵量的4.19%和18.23%,显著低于玉米着卵量。结果表明草地贪夜蛾偏好选择玉米进行取食和产卵,但在豇豆和四季豆寄主植物上可以实现种群繁衍,当其种群密度大时存在转移为害豇豆和四季豆的潜在风险。     

栎黄枯叶蛾生长发育与几种寄主内含物的关系

【目的】探讨饲喂不同寄主植物对栎黄枯叶蛾Trabala vishnou gigantina Yang生长发育及繁殖的影响,分析寄主植物内含物与其生长发育及繁殖的关系,为研究不同寄主植物对栎黄枯叶蛾种群动态的影响提供理论依据。【方法】在室内条件下,利用沙棘Hippophae rhamnoides、山杏Armeniaca sibirica、山杨Populus davidiana、旱柳Salix matsudana饲养该虫,观察幼虫发育历期、蛹历期、蛹重及产卵量等指标,同时测定寄主叶片中可溶性糖、可溶性蛋白质、水分、单宁及黄酮的含量,并进行线性回归分析。【结果】不同寄主植物饲喂栎黄枯叶蛾幼虫的发育历期、蛹历期、蛹重及产卵量均存在显著差异。取食沙棘的幼虫历期最短,仅为(74.50?1.76)d,而取食旱柳历期最长,达(106.00?1.51)d。取食山杨的蛹历期最长,为(44.00?1.41)d,最短的是取食旱柳的,仅为(32.70?3.13)d。饲喂沙棘和山杏的雌、雄蛹重和成虫产卵量显著高于饲喂山杨和旱柳的。对不同寄主的营养物质、次生物质和水分含量测定结果表明:不同寄主间营养物质、次生物质与水分的含量差异显著。回归相关分析表明:幼虫发育历期与寄主植物可溶性蛋白质含量呈显著负相关;雌蛹重和产卵量与寄主植物可溶性糖含量呈显著负相关;雌、雄蛹重与寄主植物含水量呈显著正相关;蛹历期与单宁含量呈显著正相关,但黄酮含量的高低与栎黄枯叶蛾生长发育等指标无相关性。【结论】沙棘是栎黄枯叶蛾生长发育及繁殖的最适寄主植物;并且寄主植物中可溶性糖、单宁的含量低、含水量和可溶性蛋白质含量高有利于栎黄枯叶蛾的生长发育和繁殖。     

不同食物和寄主植物对枣实蝇生长发育的影响

【目的】为了明确不同寄主植物和食物对枣实蝇Carpomyia vesuviana Costa生长发育的影响。【方法】本研究以蜂蜜、酵母膏液、白砂糖等为饲料,按不同的配比配成饲料饲养枣实蝇,观察其对枣实蝇成虫性成熟、交配产卵以及寿命的影响。此外,在室内条件下[(30±1.0)℃,14L:10D],使枣实蝇在枣果和杏果上产卵,观察枣实蝇对两种寄主果实上的产卵、幼虫发育、蛹特性、羽化率以及性比的影响。【结果】不同配方的4种饲料对成虫性成熟、交配期和产卵量和雌雄成虫寿命有显著影响;配方B饲养的枣实蝇成虫平均交配前期、交配期和产卵痕数、雌雄成虫寿命分别为5 d、5.2 h、2.87个/果实、38 d和19.5 d。与配方A、C、D均有显著性差异(P0.05),雌虫寿命在配方A和配方D之间有显著差异,与配方C无显著差异。但雄虫寿命各配方间均无显著差异。两种寄主植物(枣和杏)果实上的产卵痕数量相比,枣果上的产卵痕数量比杏果多两倍,在枣果上发育的蛹长度、宽度和蛹重分别为4.01mm、1.67 mm、4.6 mg,显著大于杏果发育的蛹。此外,在枣果上发育的蛹羽化率和性比显著高于杏果的,分别为枣果的80%和2.4:1,而杏果的56.6%和1.8:1。研究结果对枣实蝇防控有实际意义。     

不同寄主植物上马铃薯甲虫种群生长发育的比较研究

马铃薯甲虫Leptinotarsa decemlineata (Say)是马铃薯Solanum tuberosum等茄科作物上的一种毁灭性害虫。为了探明寄主植物对新疆马铃薯甲虫种群生长发育的影响, 本研究通过非选择性试验测定了马铃薯、 茄子Solanum melongena和番茄Lycopersicon esculentum 3种栽培寄主及野生寄主中亚天仙子Hyoscyamus pusillus对马铃薯甲虫种群生长发育、 存活、 繁殖及生命表参数的影响。结果表明： 马铃薯甲虫幼虫虽然能够取食番茄, 但幼虫的发育历期长、 存活率低且蛹不能羽化, 表明番茄不是新疆马铃薯甲虫种群的适宜寄主。马铃薯、 茄子、 中亚天仙子3种寄主植物对该虫卵、 幼虫、 蛹的存活率和发育历期及成虫产卵前期没有显著影响, 但对蛹重和繁殖力影响显著。取食不同寄主植物后, 该虫蛹重和繁殖力从大到小的次序为： 马铃薯＞茄子＞中亚天仙子; 种群的净增殖率(R₀)、 内禀增长率(r_m)和种群趋势指数(I)从大到小依次为： 马铃薯＞茄子＞中亚天仙子。因此马铃薯为新疆马铃薯甲虫种群的最适宜寄主, 其次为茄子和中亚天仙子, 而番茄为不适宜寄主。     

橘小实蝇与番石榴实蝇卵及蛹的种间竞争

【背景】实蝇的竞争可能发生在生活史的各个阶段,但未见卵和蛹的种间竞争的相关报道。【方法】将橘小实蝇与番石榴实蝇的卵及蛹按照相应的比例或龄期分别进行混合培养,分析2种实蝇的卵或蛹混合后的发育历期和存活率是否受到彼此影响。【结果】橘小实蝇与番石榴实蝇的卵同龄等量混合,对彼此卵的历期和孵化率无影响。当橘小实蝇和番石榴实蝇的蛹为新鲜蛹时,分别与比它们蛹龄大1 d的对方蛹混合,蛹的羽化率分别为(87.67±3.61)%和(84.33±2.56)%,显著小于对照,说明在此混合蛹处理中,后化蛹者的发育可能受到先化蛹者的抑制。【结论与意义】总体上,在卵和蛹期,橘小实蝇与番石榴实蝇未产生竞争作用;但不排除蛹期竞争的可能性,这种竞争可能存在于特定的蛹期。     

Effects of fruit fly host, fruit species, and host egg to female parasitoid ratio on the laboratory rearing of Biosteres arisanus

The host suitability of the oriental fruit fly, Bactrocera dorsalis (Hendel), for development of Biosteres arisanus (Sonan), a braconid parasitoid, was compared with three other fruit fly species, namely, Mediterranean fruit fly, Ceratitis capitata Weidemann, melon fly, Bactrocera cucurbitae Coquilett, and Malaysian fruit fly, Bactrocera latifrons (Hendel). In addition, effects of five different fruit species, namely, Carica papaya L. (solo papaya), Musa sapientum (L.) O. Ktze. (apple banana), Mangifera indica (L.) (Haden mango), Terminalia catappa (L.) (false kamani), and Citrus aurantiifolia (Christman) Swingle (common lime), on the parasitization rate of B. dorsalis and sex ratio of parasitoid progenies were evaluated. Effects of host egg to female B. arisanus ratios on parasitoid progeny yields were likewise determined. The host suitability of fruit flies for development of B. arisanus was ranked as: B. dorsalis>C. capitata=B. latifrons=B. cucurbitae. Based on percent parasitization of B. dorsalis, preference of B. arisanus females for host eggs varied with fruit species, however, preferential oviposition displayed by female parasitoids did not influence sex ratios of subsequent parasitoid progenies. Increases in host egg to female parasitoid ratios of 5:1, 10:1, 20:1, 25:1, and 30:1 corresponded with increases in parasitoid progeny yield reaching a plateau at 20:1.     

Laboratory evaluation of the chemosterilant lufenuron against the fruit flies Ceratitis capitata, Bactrocera dorsalis, B. cucurbitae, and B. latifrons

Four species of tephritid fruit flies, Ceratitis capitata, Bactrocera dorsalis, B. cucurbitae, and B. latifrons were evaluated for toxic, developmental, and physiological responses to the chemosterilant lufenuron. No significant mortality of laboratory strains of the first three species was observed after their exposure up to 50 μg/mL of lufenuron in agar adult diet, whereas B. latifrons adults fed with 50 μg/mL of lufenuron in the diet caused significant mortality compared to the control. Fertility of C. capitata adults fed on 50 μg/mL lufenuron-fortified diet between 7 and 12 days of age was approximately 46% of the no lufenuron control. Fertility of B. dorsalis and B. latifrons adults fed on 50 μg/mL lufenuron-incorporated diet was about 45% and 62% of the control, respectively. Lufenuron did not significantly affect fertility of B. cucurbitae adults. Lufenuron did not affect fecundity of C. capitata and B. dorsalis. Fecundity of B. cucurbitae and B. latifrons was not evaluated due to difficulty to count the eggs laid deep in the agar diet. Larvae fed on a liquid larval diet with ≤ 0.1 μg/mL of lufenuron were also evaluated. Pupal recovery, adult emergence, adult fliers, mating, egg hatch, and egg production of C. capitata were significantly decreased, while for B. dorsalis, pupal recovery, larval duration and adult emergence were affected. No effect of lufenuron on B. cucurbitae larvae was observed. B. latifrons was not performed because shortage of eggs at the time of this research. Lufenuron is a potential agent for management and control of C. capitata and B. dorsalis.     

The effect of dietary restriction on longevity,fecundity, and antioxidant responses in the oriental fruit fly, Bactrocera dorsalis (Hendel) (Diptera: Tephritidae)

Recent studies in fruit flies have imposed dietary restriction (DR) by diluting yeast and have reported increased lifespan as the yeast-to-sugar ratio decreased. In this study, the effects of DR on the lifespan of Bactrocera dorsalis were investigated using constant-feeding diets with different yeast:sugar ratios and an intermittent-feeding diet in which flies ate every sixth day. Antioxidant enzyme activities and the malondialdehyde concentration were also measured in virgin females under constant-feeding DR protocols to investigate their relationships with lifespan. The results showed that B. dorsalis lifespan was significantly extended by DR, and carbohydrate-enriched diet may be important for lifespan-extension. Female flies lived significantly longer than males at all dietary levels under both feeding regimes, indicating no interaction between diet and sex in determining lifespan. Antioxidant enzyme activities increased with the amount of yeast increased in the diets (0–4.76%) between starvation and DR treatments, indicating that the antioxidants may have influences in determining lifespan in B. dorsalis under starvation and DR treatments. However, antioxidants cannot keep up with increased oxidative damage induced by the high yeast diet (25%). These results revealed that the extension of lifespan by DR is evolutionarily conserved in B. dorsalis and that yeast:sugar ratios significantly modulate lifespan in this species.     

蝇蛹俑小蜂对橘小实蝇和瓜实蝇的偏好性

【背景】蝇蛹俑小蜂是实蝇类害虫蛹期的一种重要寄生蜂,对压制下一代实蝇类害虫的种群数量具有重要作用,但有关其对不同实蝇害虫的寄生特性尚缺乏研究。【方法】采用"H"型装置和培养皿测定方法,研究了蝇蛹俑小蜂的寄主选择偏好性。【结果】蝇蛹俑小蜂在橘小实蝇蛹和瓜实蝇蛹共存的情况下,偏好在橘小实蝇蛹上停留,且寄生率较高,最高寄生率达61.11%。【结论与意义】本研究为合理利用蝇蛹俑小蜂控制实蝇类害虫提供了理论基础。     

Insect oviposition plasticity in response to host availability: the case of the tephritid fruit fly Bactrocera dorsalis

1. Insect oviposition behaviour is ecologically and physiologically plastic. For tephritid fruit flies, Bactrocera dorsalis Hendel, host availability varies spatially and temporally. Females are expected to adopt adaptive oviposition strategies to maximise lifetime reproductive fitness, including survival. Bactrocera dorsalis oviposition tactics in response to different host availabilities were investigated. 2. This study includes three treatments: (i) variable host densities (host density varied according to a fixed cycle from day to day over values of 1, 5, 10 and 20 hosts per cage), (ii) a fixed high host density (20 hosts per cage), and (iii) a fixed low host density (1 host per cage). 3. Daily egg‐laying number per female over the course of 27 days was entirely independent of host density and highly dependent on female age. As host availability increased, females accepted significantly more hosts, generally laid small egg clutches, and more broadly distributed the eggs. 4. Tephritid fruit flies adaptively adjusted egg clutches in ways that reflected the variability of host availability. Egg‐ and time‐limitation constraints appeared to drive these adjustments. Female egg maturation was triggered by oviposition activity and reflected marked lifetime trade‐offs. Such strategies involved specific time schedules for egg laying. 5.This study defined the oviposition plasticity of the tephritid fruit fly. These results have general implications for the behavioural ecology of insect herbivores and parasitoids.     

Oviposition response and development of the egg-pupal parasitoid Fopius arisanus on Bactrocera oleae, a tephritid fruit fly pest of olive in the Mediterranean basin

To date, information is wanting with regard to the use of new exotic parasitoids against olive fruit fly, Bactrocera (=Dacus) oleae (Gmelin) (Diptera: Tephritidae), a serious pest of olives Olea europaea L., in the Mediterranean basin. We investigated the oviposition response and developmental biology on B. oleae of Fopius (=Biosteres) arisanus (Sonan) (=Opius oophilus Fullaway) (Hymenoptera: Braconidae), an egg-pupal parasitoid of tephritid fruit flies, never tested before as a potential parasitoid of this host. Our results showed that olive fruits infested with B. oleae eggs exerted a relevant attraction to gravid F. arisanus and represented a stimulus for oviposition. Nevertheless they were not as attractive to female parasitoids as the Mediterranean fruit fly, Ceratitis capitata Wiedemann (Diptera: Tephritidae), eggs infested papaya fruits (Carica papaya L.). In our experimental conditions, F. arisanus completed development in B. oleae within 33 ± 1.7 days (males) and 35 ± 1.6 (females). Increases in host egg to female parasitoid ratios of 1:1, 5:1, 10:1 and 20:1 corresponded with decreases in the percentage of B. oleae parasitisation and host killing but corresponded also with increases in absolute parasitisation. Our findings are discussed in light of possibilities of utilising F. arisanus for biological control of olive fruit fly.     

Host species and vegetable fruit suitability and preference by the parasitoid wasp Fopius arisanus

Parasitoids that oviposit in a concealed host inside a plant part need to be able to find both the plant and the host. Egg parasitoids of fruit‐infesting Tephritidae need to assess the oviposition site based both on the host egg and the infested fruit. Infestation by Tephritidae fruit flies threatens fruit and vegetable production. Management methods have been implemented including biological control, using Fopius arisanus Sonan (Hymenoptera: Braconidae). The parasitism by F. arisanus in three Tephritidae flies in vegetable fruits was investigated. Laboratory assays were conducted to assess the parasitoid's preference and survival. Zucchini, sweet pepper, and tomato were artificially infested with eggs of Bactrocera dorsalis Hendel, Ceratitis capitata Wiedemann, and Ceratitis cosyra Walker (all Diptera: Tephritidae), then exposed to mated naïve F. arisanus females in a 20:1 egg:parasitoid ratio. Parasitoid behavioral activities (resting, antennating, probing, ovipositing) were observed on the infested fruits. Parasitism rate was determined by dissection of fruit fly eggs under a stereomicroscope. Behavioral activities of F. arisanus differed between all the fruits when infested with B. dorsalis or C. cosyra eggs but differed only between some of the fruits when infested with C. capitata. Fopius arisanus preferred B. dorsalis over C. capitata and C. cosyra, with a parasitism rate 2× higher on B. dorsalis compared to the Ceratitis species. Preference for fruits was dependent on the infesting fruit fly. The emergence of F. arisanus was higher with B. dorsalis than with Ceratitis spp. Although B. dorsalis completed its development earlier than Ceratitis spp., host fly species did not affect the developmental time of F. arisanus. We discuss the significance of F. arisanus preference in relation to naturally occurring Tephritidae infestations. We also discuss whether some fruits might constitute a refuge for Tephritidae flies and whether this will affect the current biological control efforts against B. dorsalis.     

植物果实、颜色和形状对橘小实蝇产卵选择的影响

橘小实蝇Bactrocera dorsalis(Hendel)是近几年入侵江苏南部地区,严重危害当地水果、蔬菜的重要害虫。为深入了解其在该地区果树、蔬菜上的产卵特性,进行植物果实、颜色和形状对其产卵选择影响的研究。实验室中"纸杯法"的产卵选择试验结果表明,橘小实蝇对不同水果的产卵偏好性由高到低依次为:柑橘、香蕉、芒果、枣、石榴、苹果、桃子、梨、李、葡萄、柿;对不同蔬菜的产卵偏好性由高到低依次为:丝瓜、豇豆、苦瓜、黄瓜、茄子、南瓜、青椒、番茄。对不同寄主颜色和形状的产卵选择特点为,雌虫常选择桔黄色、绿色,以及圆球形的寄主产卵,而较少选择黑色、方形的寄主产卵。从试验结果可以看出,寄主果实散发出的气味,及其颜色和形状对橘小实蝇的产卵选择有影响。     

Fruit trap: A detection and collection tool for opiine parasitoids (Hym.: Braconidae) of the oriental fruit fly,Bactrocera dorsalis (Dipt.: Tephritidae)

A fruit trap was developed for detection and collection of the opiine parasitoids of the oriental fruit fly,Bactrocera (=Dacus)dorsalis (Hendel). Gravid females ofBiosteres arisanus (Sonan), an egg-larval parasitoid, orDiachasmimorpha longicaudata (Ashmead) andPsytallia incisi (Silvestri), both larval parasitoids, were lured to parasitize the eggs or larvae ofB. dorsalis inoculated in ripe papaya fruits,Carica papaya L. Progenies ofB. arisanus were consistently recovered from papaya fruits inoculated withB. dorsalis eggs (subsequently referred to as egg fruit traps). Except in Moloaa on Kauai (6%), higher percentage ofB. dorsalis parasitization (range=38–43%) was recorded in Hilo, island of Hawaii and Waimanalo and Poamoho, island of Oahu. Progenies ofD. longicaudata and a fewP. incisi were recovered from papaya fruits artificially infested withB. dorsalis larvae (subsequently referred to as larval fruit traps). The recovery of parasitoid progenies from larval fruit traps suspended from papaya trees did not differ significantly from larval fruit traps placed on the ground. In both methods of trap placement, percent parasitization ofB. dorsalis byD. longicaudata (predominant species) ranged from 58–60%. On the other hand, significantly moreB. arisanus thanD. longicaudata andP. incisi adults (larval parasitoids) were recovered from fully ripened to highly deteriorated papaya fruits collected from papaya trees or ground (fallen fruits).