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.     

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.     

植物源农药对橘小实蝇的毒杀及引诱作用研究

在室内条件下采用药膜法,分别测定了3种植物源生物杀虫剂对橘小实蝇成虫的毒力。其中GF-120（0.02%多杀霉素RB）对成虫的毒性最强,LC50值为0.23mg·kg^-1,其次为0.3%印楝素EC,毒性最小的为0.36%苦参碱EC。采用非选择性试验测定了橘小实蝇成虫对8种植物精油的趋性,结果表明,天竺葵和薄荷对橘小实蝇成虫的诱集效果最好,引诱率可达36%以上,与甲基丁香酚处理比较无显著差异,并且对雌雄虫都有效,其次为洋甘菊、鼠尾草和丁香,甜橙、罗勒和柠檬的诱集效果较差。     

橘小实蝇遗传性别品系的建立及雄性不育技术

为了更好地应用昆虫不育技术防治橘小实蝇,建立了以蛹色区分雌雄性别的橘小实蝇遗传性别品系。经过连续测交表明遗传品系能稳定遗传。质量监测表明遗传性别品系平均孵化率、蛹重、羽化率、飞出率、存活率等指标与普通种无显著差异。取遗传性别品系羽化前1、2、3天（分别用-1 d、-2 d、-3 d表示）的雄蛹,经过100 Gy的⁶⁰Co辐射后,分别与野生雌虫杂交,F1代卵的孵化率均大大低于对照组。对经过辐射处理-1 d、-2 d、-3 d的雄蛹分别进行质量检测,飞出率、存活率与对照组均无显著差异;-1 d、-2 d的羽化率之间及与对照组之间无显著差异,-3 d的羽化率与-1 d、-2 d及对照组差异均显著。取遗传性别品系的-2d的雄蛹辐射100 Gy的⁶⁰Co,获得不育雄虫,和野生雄虫一起竞争与野生雌虫交配的机会,相对不育系数为0.4923,表明不育雄虫与野生雄虫交配能力相当。田间扩散能力研究表明,不育雄虫在田间存在丰富的寄主植物的情况下不会大量扩散很远的距离。     

橘小实蝇染色体研究与相关技术探讨

以橘小实蝇Bactroceradorsalis(Hendel)性腺和唾液腺为材料,采取改良苯酚品红染色后压片法,制备染色体标本。对橘小实蝇进行染色体组型研究和唾液腺染色体形态学的观察。结果表明:橘小实蝇成虫性腺染色体数目为2n=12条,染色体长度基本呈连续性变化,其性染色体属于XX/XY型。幼虫唾液腺染色体包含5条较长的多线染色体,与成虫常染色体相对应。实验显示苯酚品红染色后压片为制备染色体标本简单有效的方法。     

近红外窄带光照下不同水果背景中桔小实蝇的图像分割

【目的】为了增强水果背景中桔小实蝇Bactrocera dorsalis Hendel（双翅目实蝇科）的识别效果,研究了该种昆虫与不同水果之间的反射光谱差异。【方法】采用紫外 可见光 近红外分光光度计测量了桔小实蝇与16种水果在400~2 500 nm波段的反射光谱。在中心波长为565 nm和827 nm的窄谱带光源及日光3种光源分别照射下,分别拍摄各种水果背景中的桔小实蝇照片,并用大津Otsu算法对照片进行二值化处理。【结果】发现桔小实蝇的反射率随波长增加而缓慢地增大,最大反射率小于40%。而16种水果的最强反射峰全部或部分落在在777～896 nm。不同水果平均最大反射率为41.10%～97.89%,与桔小实蝇在此波段的低反射率（约30%）形成强烈的反差。在827 nm中心波长窄带光源照射下拍摄的照片中,发现桔小实蝇为黑色,而背景水果呈现大面积的白色,形成高反差,桔小实蝇很容易被辨识。相反,在日光和565 nm中心波长窄带光源照射的照片中,水果背景存在较多的黑色斑块,容易与桔小实蝇的黑区混淆;或者该虫形成白斑,从而无法识别。【结论】选用近红外波段的窄带光源照射能明显提高桔小实蝇与水果图像的对比度,增强桔小实蝇的分割效果。     

Mass-rearing biology of Fopius vandenboschi (Hym., Braconidae)

Abstract:   Basic biological information concerning the reproductive activities of Fopius ( Biosteres ) vandenboschi (Fullaway) (Hym., Braconidae, Opiinae) were determined to facilitate insectary mass production. Mean (±SE) progeny production per generation (yield) of 200 ♀♀ F. vandenboschi was 6835.8 ± 433.2 and 3755.8 ± 112.4 parasitoids, with 24-h exposure to second instar Bactrocera dorsalis (Hendel), and Ceratitis capitata (Wiedemann), respectively. Ceratitis capitata as a factitious host was more sensitive to parasitism, producing a significantly higher percentage of uneclosed host puparia frequently containing parasitoid cadavers (22.5 ± 0.8%), than B. dorsalis (3.4 ± 0.2%). The overall mean production of female offspring was ≥50%♀♀ in both host species. Unlike several other opiine parasitoids, young (5-day-old) females of F. vandenboschi produced low proportion of daughters (26–37%♀♀) and significantly shifted production to female-biased offspring (53–71%♀♀) at older age intervals (16–30 days). Based on the parasitoid yield data with a 24-h exposure period to second instar host larvae of B. dorsalis , about 150 cage replicates (of 200 ♀♀ each) may be sufficient to mass produce about 1 million parasitoids of F. vandenboschi during the reproductive period of 5–30 days, with an average of 56% female offspring. A short oviposition exposure period of 6 h was not optimal for mass production of F. vandenboschi . Total yield at 6 h exposure was one-fifth the production at 24-h exposure, using B. dorsalis hosts.     

三种常见实蝇的形态学、生物学和生态学比较

对瓜实蝇Bactrocera (Tetradacus) minax (Enderlein)、桔小实蝇Bactrocera (Bactrocera) dorsalis (Hendel)和桔大实蝇Bactrocera (Zeugodacus) cucurbitae (Coquillett)的形态学、生物学、生态学等方面进行了比较和分析,包括三种实蝇在国内外的分布情况,对寄主选择的差异,各种虫态的形态特征,发育历期和生活史,并对它们的危害状况和防治方法分别作了介绍,可为3种实蝇的鉴定和防治提供参考.     

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。     

利用微卫星标记初步分析橘小实蝇4个地理种群的遗传多态性

橘小实蝇Bactrocera dorsalis(Bactrocera)(Hendel)是我国重要的检疫性害虫,对果蔬生产及其国际贸易造成很大影响。作者运用微卫星分子标记技术,用6对微卫星引物对采自我国福建、广东、云南3个地区及邻近国越南橘小实蝇种群间的遗传关系进行了初步分析,结果显示上述4个橘小实蝇地理种群间存在一定的遗传差异,地理隔离是造成这一差异的主要原因。