Feeding behaviour of Bactrocera cacuminata (Hering) (Diptera: Tephritidae) on methyl eugenol: a laboratory assay

Abstract Many dacine (Diptera: Tephritidae) species are attracted to one of two chemical substances, 4-allyl-1,2-dimethoxybenzene (methyl eugenol (ME)) or 4-( p -hydroxyphenyl)-2-butanone (cue lure). Despite the fact that these chemicals or analogs occur naturally, their significance in the biology/ecology of the Dacinae has seldom been examined. In this study, we examine the patterns in feeding behaviour of Bactrocera cacuminata (Hering), a monophagous non-pest fruit fly, on ME. Based on a laboratory assay, we found that males of this species fed on ME multiple times within a single day and on multiple days. The pattern of repeat feeding was not related to time since previous feeding or duration of prior feeding. Our results contrast those obtained on a similar study on a related polyphagous species ( Bactrocera dorsalis (Hendel)). We discuss the implications of our findings with a view to explaining the functional significance of dacine response to these plant-derived chemicals.     

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。     

云南西双版纳桔小实蝇种群动态

于1997年、2000年和2003年在云南西双版纳通过性诱剂诱捕对桔小实蝇种群动态进行了全年监测,并就气候因子及寄主种类对该种群变动的影响进行了系统分析.结果表明,桔小实蝇在西双版纳常年发生.当年11月至次年2月,桔小实蝇种群处于较低水平,3月以后种群数量逐渐上升,至6～7月形成一个种群增长高峰,此后至10月种群数量迅速下降.分析表明,影响桔小实蝇种群变化的重要因子是温度、降雨量和寄主种类.西双版纳各月均温位于桔小实蝇适温范围内,但12～2月的月平均最低温度低于桔小实蝇的适温范围,对桔小实蝇种群数量有一定抑制作用.降雨量是影响桔小实蝇种群数量变动的另一重要因子.月降雨量低于50 mm以下对桔小实蝇种群不利,而100～200 mm的月降雨量有助于桔小实蝇种群的增长.月降雨量大于250 mm以上将导致桔小实蝇种群数量下降.6～7月强降雨过程被认为是桔小实蝇在该时期种群数量下降的主要原因.芒果、番石榴、桃、梨、柑桔、龙眼和荔枝是桔小实蝇在该地区的主要寄主水果.其中,芒果和龙眼是当地桔小实蝇最喜好的寄主水果,其种植面积、挂果期和产量对桔小实蝇种群数量变动影响较大,被认为是影响该地区桔小实蝇种群变动的又一主要因素.     

云南四个瓜实蝇地理种群的遗传关系分析

对云南个不同地理区域的瓜实蝇种群(Bactrocera cucurbitae)共23个个体的线粒体DNA细胞色素b基因中的部分序列进行测定和分析,并以桔小实蝇(B.dorsalis)、番石榴实蝇(B.correct)和南瓜实蝇(B.tau)为外群种构建了不同单倍型的N-J分子系统树.在获得的26bp序列中,A+T含量约占65.0%,有个多态位点,无任何碱基插入和缺失.这些位点共定义5种单倍型,其中一种为共享单倍型.对个瓜实蝇地理种群进行Fst值和基因流动统计,Fst值为0.16667～0.20000(P＞0.05),Nm值为2.00～2.50.5种单倍型共形成了3个聚类簇.可以认为,个地理种群间均存在一定程度的遗传分化,但分化程度不高,导致遗传分化的主要因素是地理隔离,而种群遗传分化程度低与瓜实蝇所在环境条件相似有关.     

Control of copula duration and sperm storage by female Queensland fruit flies

Copula duration and sperm storage patterns can directly or indirectly affect fitness of male and female insects. Although both sexes have an interest in the outcome, research has tended to focus on males. To investigate female influences, we compared copula duration and sperm storage of Queensland fruit fly females that were intact, or had been incapacitated through decapitation or abdomen isolation. We found that copulations were far longer when females had been incapacitated, indicating that constraints imposed on copula duration by intact females had been relaxed. Repeatability of copula duration for males was very low regardless of female treatment, and this is also consistent with strong female influence. Number of sperm in the spermathecae was not influenced by female treatment, suggesting that female abdominal ganglia control the transport of sperm to these long-term storage organs. However, more sperm were found in the ventral receptacles of incapacitated females compared to intact females. Overall, results implicate cephalic ganglia in regulation of copula duration and short-term sperm storage in the ventral receptacle and abdominal ganglia in regulation of long-term sperm storage in the spermathecae.     

Biology of Bactrocera (Zeugodacus) tau (Walker) (Diptera: Tephritidae)

The biology of the fruit fly Bactrocera tau, an important horticultural pest, was studied under laboratory conditions at 25°C and 60–70% relative humidity on Cucurbita maxima. The duration of mating averaged 408.03 ± 235.93 min. After mating, the female fly had a preoviposition period of 11.7 ± 4.49 days. The oviposition rate was 9.9 ± 8.50 eggs and fecundity was 464.6 ± 67.98 eggs/female. Eggs were elliptical, smooth and shiny white, turning darker as hatching approached, and measured 1.30 ± 0.07 mm × 0.24 ± 0.04 mm. The chorion has polygonal microsculpturing and is species-specific with polygonal walls. The egg period lasts for 1.3 ± 0.41 days. The duration of the larval period is 1.2 ± 0.42, 1.7 ± 0.48 and 4.0 ± 0.94 days for first, second and third instars, respectively. Pupation occurs in the sand or soil and pupal periods are 7.0 ± 0.47 days. The life cycle from egg to adult was completed in 14.2 ± 1.69 days; the longevity of mated females and males was 130.33 ± 14.18 and 104.66 ± 31.21 days, respectively. At least two to three generations were observed from June 2008 to June 2009.     

瓜实蝇成虫在苦瓜田间的时空动态

【背景】瓜实蝇是重要的瓜果害虫,研究其在田间的时空分布可为进一步探讨成虫在栖息地的迁移规律奠定基础。【方法】试验于2013年9月17日~11月8日在广州市白云区广东省农业科学院试验基地进行。试验地面积约6900 m2,其中,苦瓜地面积为34 m×19 m。以黄绿色粘板进行诱捕取样,点算粘板上瓜实蝇雌、雄成虫个体数,以地学统计学方法研究瓜实蝇成虫的时空分布动态。【结果】瓜实蝇成虫密度有2个峰;其半变异函数多为高斯模型,在调查范围内空间格局为聚集分布,变程范围为9.648~65.580 m,空间异质性是由空间自相关引起。【结论与意义】运用Kriging插值法,由软件Surfer10.0绘制的密度等值线图清楚地反映出瓜实蝇成虫主要分布于苦瓜地内,呈现出瓜实蝇成虫被苦瓜吸引,并迅速繁殖及之后向瓜地外扩散的变动特征。     

Selection of non‐target tephritids for risk evaluation in classical biocontrol programmes against the olive fruit fly

The olive fruit fly, Bactrocera oleae (Rossi) (Diptera: Tephritidae), is the key pest of olives (Olea europaea L.). Classical biological control against this insect was previously attempted in Spain with Psyttalia concolor (Szépligeti) (Hymenoptera: Braconidae), with very limited success. Other parasitoids are now available for new classical biological control programmes. Before release of exotic parasitoids, an assessment of their potential impact on non‐target species is required. Surveys were conducted in different olive groves in south‐eastern Madrid to study wild tephritids associated with Asteraceae plants. We recorded plant species and their abundance and collected flower heads to identify and quantify tephritid species. Fruits from Rosa canina L. were also collected. After a multicriteria analysis (MCA), we propose Urophora hispanica Strobl, U. stylata (Fabricius) and Carpomya schineri (Loew) as candidates for further risk assessment experiments. Additional information on new associations between tephritid flies and Asteraceae plants and on autochthonous Hymenoptera parasitizing tephritids is provided.     

4种杀虫剂对南亚实蝇各虫态不同日龄的毒力测定

为明确南亚实蝇Bactrocera tau Walker不同发育阶段、不同日龄以及不同性别成虫对常用杀虫剂的敏感度,本研究采用胃毒法测定了杀虫剂对南亚实蝇室内种群幼虫和成虫的活性,采用浸泡法测了杀虫剂对卵和蛹的活性.结果表明4种杀虫剂对南亚实蝇不同日龄各虫态的毒杀活性存在差异,随日龄增加,各虫态对不同药剂的耐药性增加,且耐药性的强弱不同.高效氟氯氰菊酯EC对南亚实蝇卵、2日龄和5日龄幼虫具有较好的毒杀活性,LC50分别为2.88 mg/L、2.08 mg/L和6.39 mg/L,辛硫磷EC、多杀霉素SC以及高效氯氰菊酯EC的杀虫活性较差,LC50分别为4.71 mg/L、3.95 mg/L和11.60 mg/L;幼虫对高效氟氯氰菊酯EC的耐药性增长较快,对多杀霉素SC的耐药性增加较慢;多杀霉素SC对2日龄和5日龄的蛹和雌雄成虫的毒杀活性较高,但耐药性增加较快,蛹对辛硫磷EC的耐药性增长较慢,雌雄成虫均对高效氯氰菊酯EC耐药性增长较慢,不同日龄的雌成虫的耐药性均高于雄成虫.由于南亚实蝇世代重叠严重,在成虫暴发期之前,可将高效氟氯氰菊酯EC作为首选药剂使用,在成虫暴发期之后防治时可将多杀霉素SC作为优选药剂使用,防治最佳时期为各虫态的初期.     

Factors affecting the efficacy of trapping system to the peach fruit fly (PFF) males,Bactrocera zonata (Saunders) (Diptera: Tephritidae)

This study was conducted in Arab-Elmadabegh region located at the Northern West part of Assiut city at the border with the Western Desert. Four types of traps; Bottle trap, Glass McPhail trap, Plastic McPhail trap, and Abdel-Kawi trap baited with different doses of methyl eugenol (ME) were used. Obtained results indicated that Abdel-Kawi trap charged with 0.5?ml ME, it was the most effective trapping system. ME seemed to be with highly attracting effect, but most of the attracted males were found on the outside surface of the trap and on the branches surround the trap. Under these conditions, the females/males ration became 1:171. Thus, the believing tactic that fruit flies populations will decline due to the lack of males in the population available to females for mating seemed to be an erroneous believing. Results proved that PFF males had the highest activity at the dawn period between 5 and 7am. We strongly recommend using the trapping system consists of Abdel-Kawi trap charged with 0.5?ml ME only at dawn period (The first appearance of light in the morning followed by sunrise).