Population fluctuations and interspecific competition between Tephritid flies attacking fruit crops in the New Valley oases,Egypt

Population fluctuations of the Mediterranean fruit fly Ceratitis capitata (Wiedemann) and the peach fly Bactrocera zonata (Saunders) were monitored with lure trap collections in three provinces in the New Valley oases, Western Desert, Egypt. Results showed marked temporal differences in peak trap catches of the two flies in the selected sites all over the entire studied areas. One annual peak of C. capitata was recorded during both October 2005 and February 2006 and coincided with the ripening period of citrus trees in Kharga oases. However, two annual peaks were recorded during June and September 2005 in Bodkholow province and coincided with the ripening period of apple and mango. On the other hand, two annual peaks of B. zonata were recorded in Kharga oases throughout May and September and coincided with the ripening periods of apricot, mango and guava. One annual peak only was recorded in the round up of September and/or October in both Moot and Bodkholow in Dakhla oases and coincided with the ripening period of mango, guava and citrus. The occurrence of C. capitata was very limited in comparison with B. zonata. Population fluctuations of the two pests in the studied sites were significantly different. The ability of the traps used in capturing both C. capitata and B. zonata indicated that the yellow sticky trap was more effective in capturing C. capitata. However, the Abdel-Kawi trap was significantly efficient at trapping B. zonata. The occurrence of B. zontata in high numbers all over the study period compared to C. capitata is considered as good proof that this invading fly may be considered as a vigorous competitive tephritid fly to the native fly C. capitata.     

橘小实蝇、瓜实蝇和南亚果实蝇人工饲料的优化

在温度25²8℃、相对湿度70%28℃、相对湿度70%⁷5%和光照周期L∶D=14∶10条件下进行了人工大量饲养橘小实蝇Bactrocera dorsalis(Hendel)和瓜实蝇B.cucurbitae(Coquillett)成虫人工饲料配方的筛选试验。结果显示,1∶2重量比例混合的蔗糖和啤酒酵母是饲养这2种果实蝇的最佳成虫人工饲料,用其饲养的单雌产卵量、产卵期和孵化率分别为424.1675%和光照周期L∶D=14∶10条件下进行了人工大量饲养橘小实蝇Bactrocera dorsalis(Hendel)和瓜实蝇B.cucurbitae(Coquillett)成虫人工饲料配方的筛选试验。结果显示,1∶2重量比例混合的蔗糖和啤酒酵母是饲养这2种果实蝇的最佳成虫人工饲料,用其饲养的单雌产卵量、产卵期和孵化率分别为424.16⁴45.75粒,30.90445.75粒,30.90³1.87 d,74.60%31.87 d,74.60%⁷5.40%。同时,对18种由不同配方配制成的幼虫人工饲料饲养橘小实蝇、瓜实蝇和南亚果实蝇B.tau(Walker)的效果进行了比较。结果表明,玉米和麦麸作为饲料的介质优于麦片和麦麸。橘小实蝇幼虫人工饲料的优化配方为:玉米+麦麸(125 g+25 g),蔗糖25 g,啤酒酵母25 g,对羟基苯甲酸甲酯0.9 g,1 mol/L盐酸4 mL,纸巾4 g,自来水300 mL;用其幼虫人工饲料饲养该虫的生物学参数包括子代孵化率、化蛹率、羽化率和平均蛹重分别为81.17%±0.05%,96.41%±0.02%,94.85%±0.01%与(19.40±0.08)mg。而瓜实蝇和南亚果实蝇幼虫人工饲料的优化配方为:玉米+麦麸(100 g+50 g),蔗糖30 g,啤酒酵母25 g,以及一定量的其他组分(同上);用其饲料饲养这2种果实蝇的相关参数:子代孵化率、化蛹率、羽化率和平均蛹重分别为78.50%±0.04%与76.96%±0.12%,95.73%±0.03%与94.69%±0.02%,94.57%±0.02%与95.82%±0.03%,(18.62±0.23)mg与(22.83±1.38)mg。试验证实,优化后的成、幼虫人工饲料具有饲养效果好、方法简便,配方材料来源广泛和价格低廉等优点,可用于室内人工大量饲养上述3种果实蝇属害虫。     

橘小实蝇对五个芒果品种的产卵偏好及清理落果防治效果研究

在2011年6—8月调查了橘小实蝇Bactrocera dorsalis(Hendel)对云南省元江县5个主要芒果品种的产卵为害情况,评估了清理落果对橘小实蝇的防治效果。结果表明树上果实和成熟落果受害率最高、产卵孔数量最多的品种是三年芒和红象牙芒;单位面积落果量(X)和监测雄虫数量(Y)显著相关(r1=0.884**,显著性P1=0.000),其回归方程为Y=-1.675+449.701X-204.933X2+27.046X3(R2=0.966,显著性水平P=0.000);累加虫量(X)与树上果实被害率(Y)的回归方程为Y=0.003X0.721(R2=0.953,P=0.000)。采拾落果可降低树上果实受害率约20%,减少田间虫口数44%左右。因此,清理落果对控制橘小实蝇田间种群数量、减少树上果实被害率有显著作用。     

Synergistic and additive interactions among components of food-based baits underlie female fruit fly attraction

Attraction of tephritid fruit flies to some food sources can be enhanced by the presence of ammonia derivatives, compounds that are perceived as volatile cues for protein-rich food sources. Using a comparative approach, we (1) evaluated the behavioral responses of females of three invasive fruit fly species, Bactrocera (Zeugodacus) cucurbitae (Coquillett), Bactrocera dorsalis (Hendel), and Ceratitis capitata (Wiedemann) (all Diptera: Tephritidae) to trub (a protein-rich waste brewer’s yeast product generated during the production of beer), Concord grape juice (a protein-deficient material), and ammonium acetate, and (2) identified synergistic and additive interactions between low- and high-attractiveness materials and ammonium acetate. We established the attractiveness of fresh trub, grape juice, and ammonium acetate when tested singly to females of all three fly species. Although ammonium acetate did not enhance significantly the response of females of any species to fresh trub, the most attractive material, ammonium acetate, did significantly enhance females’ level of response to aged trub (a comparatively less attractive material) and to grape juice. Our research found a synergistic interaction between diluted grape juice and ammonium acetate for B. cucurbitae, as well as between aged trub and ammonium acetate for B. dorsalis. For C. capitata, additive effects among food attractants and ammonium acetate were identified. Our findings increase our understanding of fruit fly female olfactory-driven behavior in response to food-based materials and the extent to which ammonium acetate modulates female response to protein-rich and protein-deficient materials.     

基于mtDNA COI基因序列的中国柑橘果实蝇的分子鉴定及柑橘大实蝇种群的遗传多样性分析

【目的】探明危害我国柑橘的实蝇种类以及柑橘大实蝇Bactrocera minax不同地理种群和不同寄主种群的遗传多样性。【方法】利用mtDNA COI基因对危害柑橘的果实蝇进行种类鉴定,采用MEGA软件对其中28个地理种群的535头果实蝇COI基因片段(约505 bp)序列进行比对,分析种间及种内遗传距离,构建系统发育树。使用DnaSP软件分析柑橘大实蝇不同地理种群和不同寄主种群的遗传多样性。【结果】从柑橘虫果内共鉴定出4种实蝇,分别为柑橘大实蝇B.minax、桔小实蝇B.dorsalis、蜜柑大实蝇B.tsuneonis和瑞丽果实蝇B.ruiliensis。这4种实蝇的种间遗传距离为0.0264～0.2410,种内遗传距离为0.0000～0.0140,种间与种内遗传距离没有重叠区域。单个柑橘虫果内一般仅有1种实蝇,极个别柑橘果实可同时被两种实蝇危害(4/43);在这些为害柑橘的实蝇种类中,以柑橘大实蝇的个体数量比例最大,占90.70%。柑橘大实蝇地理种群遗传多样性高,28个种群共有17个单倍型。【结论】柑橘大实蝇是所调查地区柑橘实蝇的绝对优势种,其种群遗传分化程度较高,扩散危害风险大。本研究结果对柑橘果实蝇类的监测和防控具有重要意义。     

Preference and performance of Diachasmimorpha kraussii (Fullaway) (Hymenoptera: Braconidae) on five commercial fruit species

Diachasmimorpha kraussii is a polyphagous endoparasitoid of dacine fruit flies. The fruit fly hosts of D. krausii, in turn, attack a wide range of fruits and vegetables. The role that fruits play in host selection behaviour of D. kraussii has not been previously investigated. This study examines fruit preference of D. kraussii through a laboratory choice‐test trial and field fruit sampling. In the laboratory trial, oviposition preference and offspring performance measures (sex ratio, developmental time, body length, hind tibial length) of D. kraussii were investigated with respect to five fruit species [Psidium guajava L. (guava), Prunis persica L. (peach), Malus domestica Borkh. (apple), Pyrus communis L. (pear) and Citrus sinensis L. (orange)], and two fruit fly species (Bactrocera jarvisi and B. tryoni). Diachasmimorpha kraussii responded to infested fruit of all fruit types in both choice and no‐choice tests, but showed stronger preference for guava and peach in the choice tests irrespective of the species of fly larvae within the fruit. The wasp did not respond to uninfested fruit. The offspring performance measures differed in a non‐consistent fashion between the fruit types, but generally wasp offspring performed better in guava, peach and orange. The offspring sex ratio, except for one fruit/fly combination (B. jarvisi in apple), was always female biased. The combined results suggest that of the five fruits tested, guava and peach are the best fruit substrates for D. krausii. Field sampling indicated a non‐random use of available, fruit fly infested fruit by D. kraussii. Fruit fly maggots within two fruit species, Plachonia careya and Terminalia cattappa, had disproportionately higher levels of D. krausii parasitism than would be expected based on the proportion of different infested fruit species sampled, or levels of fruit fly infestation within those fruit.     

Effectiveness of plastic matrix lures and traps against Bactrocera dorsalis and Bactrocera cucurbitae in Hawaii

Trapping trials were conducted in two locations on the island of Hawaii with plastic‐matrix formulations of methyl eugenol (ME) (1‐2‐dimethoxy‐4‐allylbenzene) and cuelure (CL) [4‐(p‐acetoxyphenyl)‐2‐butanone] in traps with or without a toxicant (2, 2‐dichlorovinyl dimethyl phosphate, DDVP) against wild fly populations of oriental fruit fly, Bactrocera dorsalis (Hendel) and melon fly, Bactrocera cucurbitae (Coquillett) respectively. Both 5 g disks and 10 g cones of ME and 2 g plugs of CL caught flies for >9 months which varied relative to the population fluctuations. In all of these trials a one‐way entrance design trap caught more flies than the toxicant‐baited trap. The similar‐sized entrance holes (0.70 cm) of the latter may have slowed the dispersal of the toxicant vapour, thus causing flies to be repelled or killed outside the entrance to the trap when DDVP vapour was evolving at a maximum rate. The effect decreased as the toxicant aged. One‐way entrance traps are appropriate where toxicant traps are not allowed (e.g. organic farms), present a health hazard (e.g. yards with children), or would need to be replaced more frequently than lures. The results of these studies are discussed in relation to areawide fruit fly suppression programs where large populations of these flies are persistent, as well as to detection programs in areas where fruit flies have not established.     

中国海南果实蝇属三新种记述(双翅目,实蝇科,寡鬃实蝇亚科)(英文)

系2005～2010年海南省实蝇监测和野外调查的部分研究结果,记述实蝇科Tephritidae果实蝇属Bactrocera Macquart 3新种,并附其形态特征图。模式标本保存于海南出入境检验检疫局热带植物隔离检疫中心昆虫标本馆。     

Influence of fruit traits on oviposition preference and offspring performance of Bactrocera tryoni (Froggatt) (Diptera: Tephritidae) on three tomato (Lycopersicon lycopersicum) cultivars

Abstract  In Queensland, three tomato ( Lycopersicon lycopersicum ) cultivars, Grosse Lisse, Roma and Cherry, are infested by Queensland fruit fly, Bactrocera tryoni (Froggatt). In this study, we examined if there was a correlation between oviposition preference and offspring performance of B. tryoni among the three tomato cultivars. We also investigated host plant traits that may explain any variation in preference and performance. Choice and no-choice experiments were carried out under laboratory conditions. A positive correlation between oviposition preference and offspring performance of B. tryoni was observed in the three tomato cultivars. Grosse Lisse and Roma cultivars were highly preferred by B. tryoni over Cherry cultivar. Performance (measured as proportion of eggs developing to the pupal stage) was significantly higher in Grosse Lisse and Roma cultivars than in Cherry cultivar. The pericarp toughness of Cherry cultivar appears responsible for its low rate of infestation, while the presence of 2-butanol and 1,4-butanediamine in Roma and Grosse Lisse, respectively, may partly be responsible for the high oviposition preference shown by B. tryoni towards these cultivars.