Host suitability of three avocado cultivars (Persea americana Miller: Lauraceae) to oriental fruit fly (Bactrocera (invadens) dorsalis (Hendel) (Diptera: Tephritidae))

The oriental (invasive) fruit fly Bactrocera (invadens) dorsalis (Hendel) (Diptera: Tephritidae) has invaded Africa and is currently established in over 30 countries and has caused in massive fruit losses. Avocado (Persea americana Miller) is among the fruit with which the pest is associated. The aim of the study was to determine the host status of a ‘black-skinned’ cultivar “Hass” and two ‘green-skinned’ cultivars “Pinkerton” and “Fuerte” to B. (invadens) dorsalis. In the laboratory study conducted in Kenya in 2012 and 2013, punctured and unpunctured recently-harvested fruit were exposed to sexually-mature fruit fly in ‘no-choice’ experiments. B. (invadens) dorsalis readily developed in the punctured fruit but not in the uncompromised fruit (fruit not damaged by insects or handling). This result was confirmed in Tanzania in 2013 where flies were introduced to unpunctured fruit. In the field studies the fruit of each cultivar were caged in situ with flies for 72 h. On dissection only fruit damaged by false codling moth (Thaumatotibia leucotreta (Meyrick)) were found to harbor B. (invadens) dorsalis. In the light of these results the risk imposed for “Hass”, “Pinkerton” and “Fuerte” by B. (invadens) dorsalis is negligible under standard export conditions. The findings of this study and the implications to regional and international trade are discussed.     

Correlation of fruit fly (Diptera Tephritidae) infestation of major mango cultivars in Borgou (Benin) with abiotic and biotic factors and assessment of damage

Fruit flies associated with mango trees were monitored in two orchards in Benin using traps baited with methyl eugenol, terpinyl acetate and Torula during 2005–2006. Population fluctuations were analysed with respect to environmental factors including air temperature, relative humidity and rainfall in relation to different mango cultivars. Mangoes were sampled every two weeks during the two crop years, to assess the damage caused by these quarantine pests on ten main cultivars. Three native species of Ceratitis and a recently described new exotic species, Bactrocera invadens made up the complex of economically significant fruit flies associated with the mango tree in Borgou. Ceratitis species occurred during the dry season and the main species, Ceratitis cosyra, reached a peak at the end of the dry season. B. invadens populations were scarce during the dry season, but increased steadily from the end of April to reach a peak at the end of June during the rainy season. Regression analyses indicated that minimum–maximum temperature, relative humidity and rainfall were the major climatic factors influencing fly populations. Daily rainfall was the factor showing the strongest positive correlation with B. invadens populations. Host plant was another essential factor influencing the population fluctuations. Trapping and rearing data indicated that Ceratitis quinaria and Ceratitis silvestrii, were abundant only in the dry season, causing damage only to early cultivars. C. cosyra, also common during the dry season, attacked both early cultivars or mid season cultivars. A consistent population increase of B. invadens in the early rainy season caused considerable damage to mid season and late cultivars. The seasonal increase of the B. invadens population coincided with the fruiting period of the main mango cultivars in this Northern Guinean savannah, but mango availability influenced the population of this new invasive species only when the rains had arrived. Mean damage on mangoes for the two seasons and two studied orchards increased from 17% in early April to 73% at mid June.     

Spatial and temporal abundance of the solanum fruit fly, Bactrocera latifrons (Hendel), in Morogoro,Tanzania

Bactrocera latifrons is a newly invasive pest species in eastern Africa. Surveys to determine the spatial and temporal abundance of this fruit fly in the Morogoro Region, Eastern Central Tanzania, were conducted from April 2007 to March 2008. The surveys involved trapping of adult flies and collection of host fruits to determine the emergence of adults. The results indicated that the population of B. latifrons was generally low but that adult flies were present throughout the survey period. The population of B. latifrons based on infestation rates and incidence in host fruits, seems to be relatively high during the wet seasons, probably because of availability of many hosts. However, the population of the pest as determined by trapping, indicated a low population but without a specific pattern. The pest shows minimal response to the used attractants. The surveys further indicate that B. latifrons is more abundant in low to medium altitude areas compared to high altitude areas. The results indicate that, because of its low population, B. latifrons might be a minor pest. Results further suggest the possibility of establishing B. latifrons free areas where export valued solanaceous crops can be grown, but further research over longer periods would be needed to establish this.     

A comparison of monitoring systems used for Ceratitis species (Diptera: Tephritidae) in South Africa

For 16 years a bucket-type trap known as the Sensus fruit fly trap has been used to monitor three fruit fly pest species Ceratitis capitata, Ceratitis rosa and Ceratitis cosyra in South African fruit industries. The relative efficiencies of lures sold for monitoring fruit flies with the Sensus trap in South Africa were determined in field experiments where laboratory-reared C. capitata, C. rosa and C. cosyra were released in a mango orchard within a few metres of Sensus traps containing either Capilure (trimedlure or tert-butyl 4 (or 5) -chloro-2-methylcyclohexane carboxylate), Ceratitislure (protein hydrolysate plus β-caryophyllene) or Questlure (protein hydrolysate plus plant extracts). When using 12-day-old flies, Capilure caught 3 times more C. capitata males than C. rosa males and this difference was more extreme when 3-day-old flies were released. Ceratitislure caught significantly more 12-day-old C. cosyra males than 12-day-old C. capitata males, but the difference was reversed when 3-day-old flies were compared. Questlure showed the least differences between species and age but recovered the lowest proportion of released species. Further comparisons were conducted in an orchard with wild flies using other known attractants in larger yellow Probodelt bucket traps. Capilure caught more male C. capitata than BioLure Fruit Fly 3-component, but BioLure 2-component (trimethylamine and ammonium acetate) was more effective than Questlure for C. capitata females. The 3-component lure was also more effective than both Capilure and Questlure for male and female C. rosa, respectively. Ceratitislure was the most effective lure for male C. cosyra flies and BioLure 3-component was more effective than Ceratitislure and Questlure for female C. cosyra flies. The intervention threshold of 4 flies/trap/week previously used in citrus with Capilure for C. rosa was lowered to 2 C. rosa/trap/week when using the Sensus trap due to the lower sensitivity of this trap-lure combination found for C. rosa in this study. The 3-component lure, or the 2-component combination of trimethylamine and ammonium acetate in a ratio of 1:8 in the Sensus trap capsule, would be more effective for both sexes of all three Ceratitis species than the Questlure that is currently being used.     

Pollination Services of Mango Flower Pollinators

Measuring wild pollinator services in agricultural production is very important in the context of sustainable management. In this study, we estimated the contribution of native pollinators to mango fruit set production of two mango cultivars Mangifera indica (L). cv. ‘Sala’ and ‘Chok Anan’. Visitation rates of pollinators on mango flowers and number of pollen grains adhering to their bodies determined pollinator efficiency for reproductive success of the crop. Chok Anan failed to produce any fruit set in the absence of pollinators. In natural condition, we found that Sala produced 4.8% fruit set per hermaphrodite flower while Chok Anan produced 3.1% per flower. Hand pollination tremendously increased fruit set of naturally pollinated flower for Sala (>100%), but only 33% for Chok Anan. Pollinator contribution to mango fruit set was estimated at 53% of total fruit set production. Our results highlighted the importance of insect pollinations in mango production. Large size flies Eristalinus spp. and Chrysomya spp. were found to be effective pollen carriers and visited more mango flowers compared with other flower visitors.     

Response of two tephritid species, Bactrocera oleae and Ceratitis capitata, to different emission levels of pheromone and parapheromone

Attractants and pheromones are commonly used in integrated pest management programs in crop systems. However, pheromone dispensers employed in monitoring traps and lure and kill devices are not usually well studied and attractants are released at uncontrolled rates leading to low treatment efficacies and misleading monitoring estimations. Fruit flies are pests of economic importance and monitoring is essential in order to program insecticidal treatments. Moreover, lure and kill techniques are being increasingly used, but the cost of these techniques depends on the number of required traps and, therefore, on the efficacy of the attractants. Ceratitis capitata and Bactrocera oleae are the two main fruit flies in Mediterranean countries, and the effect of different doses of trimedlure and spiroacetal on fly attraction has been studied. Results showed that a release rate over 1.28 mg/day of spiroacetal reduces B. oleae attraction and emission values over 2.4 mg of trimedlure per day did not increase C. capitata catches. Under the environmental conditions of our study, an optimum release rate for pheromone attraction in B. oleae was determined. Emission values over this optimum level reduced B. oleae attraction. However, when a parapheromone was used with C. capitata, a fruit fly of the same family, the optimum emission value was not found and higher quantities of parapheromone attracted the same number of flies. The saturation effect of high concentrations of pheromone and parapheromone is discussed.     

Area-wide management of fruit flies (Diptera: Tephritidae) in the Central Burnett district of Queensland,Australia

Queensland fruit fly, Bactrocera tryoni (Froggatt), is the most serious pest of the native tephritid species in Australia and a significant market access impediment for fruit commodities from any area where this species is endemic. An area-wide management (AWM) program was implemented in the Central Burnett district of Queensland with the aim of improving fruit fly control and enhancing market access opportunities for citrus and other fruits produced in the district. The primary control measures adopted in the AWM system included bait spraying of commercial and non-commercial hosts and the year-round installation of male annihilation technology (MAT) carriers in both orchards and town areas. The MAT carrier used consisted of a dental wick impregnated with 1 ml cue-lure [4-(4-acetoxyphenol)-2-butanone] and 1 ml Malathion 500 EC in a plastic cup. The application of these control measures from 2003 to 2007 resulted in overall suppression of fruit fly populations across the entire district. Male trap catches at the peak activity time were reduced by 95% and overall fruit fly infestation in untreated backyard fruit of town areas reduced from 60.8% to 21.8%. Our results demonstrate remarkable improvement in fruit fly control and economic benefit to the Central Burnett horticulture. Therefore, commercial growers are continuing the AWM program as a long-term, industry funded activity, to provide an additional layer of phytosanitary security for market access of fruit commodities from this district.     

Histopathological Changes in Third-Instar and Adult Anastrepha ludens (Diptera: Tephritidae) After in vitro Heat Treatment

The Mexican fruit fly, Anastrepha ludens Loew (Diptera: Tephritidae), is one of the most harmful pests of mango causing direct damage by oviposition on the fruit pulp. Mango for export is subjected to hydrothermal treatment as a quarantine method for the control of this pest, but exposure to heat for long periods of time reduces considerably the quality and shelf-life of treated fruit. The aim of this work was to study morphological changes of third-instar larvae and adults of A. ludens after in vitro exposure to high temperature at sublethal times. A heating block system was used to expose larvae at 46.1°C for 19.6 and 12.9 min, producing 94.6 and 70% mortality, respectively. Treated larvae were processed for optical microscopy. A fraction of surviving treated larvae was separated into containers with artificial diet to allow development into adults. Adult sexual organs were dissected and processed for transmission electron microscopy analysis. Results showed that 94.6% of the treated larvae died at 46.1°C for 19.6 min and none of the surviving larvae eclosed to adulthood, as they developed as malformed puparia. For the in vitro treatment at 46.1°C during 12.9 min, 70% of the treated larvae died and only 3.75% reached the adult stage, but ultrastructural damage in the male testes and in the female ovaries was observed. Additionally, 11.1% of the adult flies from the in vitro treatment also showed wing malformation and were incapable of flying. The analysis showed that surviving flies were unable to reproduce.     

Pest behaviour insights from quarantine surveillance of male Queensland fruit fly,Bactrocera tryoni (Froggatt) (Diptera: Tephritidae)

Fruit flies (Diptera: Tephritidae) are a major problem for Australia's $6.9 billion horticultural industry. Bactrocera tryoni (Froggatt) is the most significant fruit fly pest in the eastern states of Australia. Catches of male B. tryoni from cuelure-baited Lynfield surveillance traps in towns bordering the Fruit Fly Exclusion Zone in New South Wales, Australia, from November to May in 2001/2002–2007/2008 were analysed with respect to year, town, property type (urban/rural), and tree species/crop varieties in which the trap was placed (tree type). Average catches of all traps were highest in 2007/2008 and lowest in 2003/2004, and showed an overall positive correlation with rainfall (P < 0.05). More B. tryoni males were caught in Wagga Wagga and Lockhart than in other towns. There were no significant differences in catches of B. tryoni between urban and rurally located traps. With respect to tree type, traps placed in pomefruit trees caught significantly more flies than those in citrus, stonefruit, or nonfruit trees, with no significant differences among the latter three tree groups. Within the pomefruit group, traps in apples (Malus domestica Borkh.) and pears (Pyrus spp.) caught significantly more flies than those in cotoneasters (Cotoneaster spp). Within the citrus group, traps in orange trees (Citrus × sinensis (L.) Osbeck) caught significantly more flies than those in mandarin trees (Citrus reticulata Blanco). No significant differences were detected in catches between any members of the stonefruit group. Within the nonfruit group, traps placed in kurrajongs (Brachychiton populneum (Schott & Endl.) R. Br.) caught significantly more flies than those placed on other tree species in the group. This study demonstrates that although surveillance programs conducted to establish and/or maintain area freedom from specific pests may not provide balanced datasets, careful analysis of the results of such programs can provide valuable insights into the behaviour of the species in question.     

Implementing a Spinosad-Based Local Bait Station to Control Bactrocera cucurbitae (Diptera: Tephritidae) in High Rainfall Areas of Reunion Island

Three species of fruit flies cause serious damage to cucurbit crops on Reunion Island: Bactrocera cucurbitae (Diptera: Tephritidae) (Coquillett 1899), Dacus ciliatus (Loew 1901), and Dacus demmerezi (Bezzi 1917). To control them, a program of agroecological management of cucurbit flies has been implemented based on the application of Synéis-appât, especially spot sprays on corn borders. However, the high rainfall on Reunion Island limits the long-term efficiency of the bait; in addition, this method cannot be used for large chayote trellises, because corn borders cannot be planted around them. The aim of this study was to design a bait station adapted to prevailing conditions on Reunion Island. An ‘umbrella trap’ tested in Taiwan was used as a reference to compare its efficacy with our local bait station. Experiments were conducted in field cages on B. cucurbitae to test different characteristics of bait stations and to construct one using local materials. Results were validated in the field. The attractiveness of the bait station was related mainly to the color of the external surface, yellow being the most attractive color. The efficacy of the bait station with respect to fly mortality was found to be linked to the accessibility of the bait, and direct application of Synéis-appât on the bait station was found to be the most efficient. In the field, B. cucurbitae were more attracted to the local bait station than to the umbrella trap, while the two other fly species displayed equal attraction to both trap types. Our local bait station is a useful alternative to spot sprays of Synéis-appât and is now included in a local pest management program and is well accepted by farmers.     

Disruption of Darna pallivitta (Lepidoptera: Limacodidae) by Conventional and Mobile Pheromone Deployment

Identification of the Darna pallivitta (Moore) pheromone component n-butyl (E)-7,9-decadienoate (E7,9-10:COOn-Bu) has made it possible to investigate communication disruption to control this lepidopteran pest. Conventional communication disruption trials showed marked decreases in the mean number of male moths captured in E7,9-10:COOnBu-treated fields compared with control fields. For traps baited with E7,9-10:COOnBu, percent disruptions were 94.4% and 92.1% for septa (1 g pheromone/ha, 1-wk trial duration) and spirals (6 g pheromone/ha, 8-wk trial duration) respectively. For traps baited with virgin female moths, percent disruption was 73.3% using septa disruptors (1 g pheromone/ha, 1-wk trial duration). Mobile communication disruption using Bactrocera cucurbitae (Coquillett) as carriers for E7,9-10:COOn-Bu was evaluated in the following three areas: fly survivorship, attraction of male moths to treated flies, and moth disruption in a small-scale field trial. Topical application of E7,9-10:COOnBu showed no significant decrease in survivorship at 50 and 80 µg/fly. However, decreased survivorship was observed at 100 µg/fly and linear regression showed E7,9-10:COOnBu dose was significantly correlated with B. cucurbitae survivorship. Traps containing honey–pheromone-fed flies attracted and caught D. pallivitta over a 1-wk period, demonstrating the attractiveness of the carrier. Releasing E7,9-10:COOnBu-fed B. cucurbitae (∼2 g pheromone/ha, 1-wk trial duration) resulted in significantly reduced trap catches in treatment fields compared with control fields on the first 2 d of the field trial. Percent disruptions were 84.7% (day 1) and 56.0% (day 2). These results suggest that both conventional communication disruption and mobile communication disruption have potential to control D. pallivitta.     

Flight Capacity of Bactrocera dorsalis (Diptera: Tephritidae) Adult Females Based on Flight Mill Studies and Flight Muscle Ultrastructure

The oriental fruit fly, Bactrocera dorsalis (Hendel) (Diptera: Tephritidae), is considered a major economic threat in many regions worldwide. To better comprehend flight capacity of B. dorsalis and its physiological basis, a computer-monitored flight mill was used to study flight capacity of B. dorsalis adult females of various ages, and the changes of its flight muscle ultrastructures were studied by transmission electron microscopy. The flight capacity (both speed and distance) changed significantly with age of B. dorsalis female adults, peaking at about 15 d; the myofibril diameter of the flight muscle of test insects at 15-d old was the longest, up to 1.56 µm, the sarcomere length at 15-d old was the shortest, averaging at 1.37 µm, volume content of mitochondria of flight muscle at 15-d old reached the peak, it was 32.64%. This study provides the important scientific data for better revealing long-distance movement mechanism of B. dorsalis.     

Impact of Background Fruit Odors on Attraction of Drosophila suzukii (Diptera: Drosophilidae) to Its Symbiotic Yeast

Background odors produced by plants in the environment can interfere with the response of insects to a point-releasing attractant, especially when their compositions overlap. In this study, a series of binary choice tests was conducted in a wind tunnel to investigate whether background odors emitted from cherry, blueberry, blackberry, or raspberry fruits would affect the level of Drosophila suzukii (Matsumura) attraction to its symbiotic yeast, Hanseniaspora uvarum (Niehaus) (Saccharomycetales: Saccharomycetaceae). Whether an increase in the intensity of background odors would affect the attractiveness of H. uvarum to D. suzukii was also investigated, either by increasing the number of cherry or raspberry fruit per cup or by increasing the number of fruit cups surrounding the cup baited with the yeast. In wind tunnel assays, background fruit odors interfering with D. suzukii attraction to the yeast varied among fruit types. Raspberry odor inhibited the attractiveness of H. uvarum to the fly the most, followed by blackberry odor, whereas cherry and blueberry odors had no significant impact on the attraction. An increase in the intensity of odors by adding more cherry or raspberry fruit per cup did not increase the impact of fruit odor on the attraction; however, adding more raspberry cups around H. uvarum linearly decreased its attractiveness, suggesting that background host fruit abundance and likely increase in host odor may influence D. suzukii attraction to yeast odor depending on host species.     

Natural Enemies of the Frankliniella Complex Species (Thysanoptera: Thripidae) in Ataulfo Mango Agroecosystems

A field survey was conducted in Ataulfo mango (Mangifera indica L.) orchards in Chiapas, Mexico, with the objective of determining the natural enemies of the Frankliniella complex species (Thysanoptera: Thripidae). Seven species of this genus feed and reproduce in large numbers during the mango flowering. Two representative orchards were selected: the orchard “Tres A” characterized by an intensive use of agrochemicals directed against thrips, and the orchard “La Escondida” that did not spray insecticides. During mango flowering, five inflorescences were randomly collected every 5 d in both orchards, for a total of 18 sampling dates. Results revealed the presence of 18 species of arthropods that were found predating on Frankliniella. There were 11 species in the families Aeolothripidae, Phlaeothripidae, Formicidae, Anthocoridae and Chrysopidae; and seven species of spiders in the families Araneidae, Tetragnathidae, and Uloboridae. Over 88% of predators were anthocorids, including, Paratriphleps sp. (Champion), Orius insidiosus (Say), Orius tristicolor (White), and O. perpunctatus (Reuter). The orchard that did not spray insecticides had a significantly higher number of predators suggesting a negative effect of the insecticides on the abundance of these organisms.     

海南岛热带水果种植结构时空变化分析

热带水果产业是海南农民增收致富的支柱产业,分析海南建省以来热带水果种植结构的演变历程与驱动因素,有助于提出相应的调整优化策略,推动海南岛热带水果产业优化升级。本研究运用重心分析、空间分析及回归分析法,研究海南岛各市（县）1988—2020年热带水果种植结构类型演变、种植比例变化趋势、生产重心迁移及驱动因素。结果表明：（1）海南岛热带水果面积呈现波动上升趋势,主要种植芒果、香蕉、荔枝、菠萝、柑橘橙柚、龙眼等,龙眼生产重心移动距离最大,菠萝生产重心移动距离最小。（2）海南岛热带水果总体种植结构类型为芒果、香蕉、荔枝、菠萝的单一或组合类型,单一水果、2种水果组合、3种水果组合类型数量之比为48∶0∶52;市县热带水果种植结构类型为香蕉、芒果、荔枝、菠萝、龙眼、柑橘橙柚的单一或组合类型,单一、2种、3种水果组合类型数量之比为78∶9∶13。（3）市（县）热带水果种植结构空间集聚特征明显,经历了集聚、分散、再集聚的过程,大部分市（县）已形成稳定的主导种植结构,少部分市（县）仍在不断调整探索;主要水果种植比例变化趋势相同的区域集聚性更显著。（4）海南岛热带水果种植结构演变的驱动因素主要包括自然环境、政策扶持、社会需求、市场行情和农垦改革。应在充分了解当地水果种植结构演变历程及驱动因素的基础上,遵循自然资源条件,以市场需求为导向,综合考虑经济社会发展与生态保护等其他因素,合理调控产业规模,推动当地形成具有地方优势与特色的水果种植结构,促进海南岛热带水果产业整体向稳定、高质量发展。     

Ca~(2 )对芒果果实后熟效应的研究

以７～８成熟的芒果果实为材料,比较果实减压渗钙与否对后熟的效应,研究与果实后熟相关酶类的活性和钙调蛋白（ＣａＭ）含量的动态变化,寻找它们之间的相互关系。结果表明：对照果实或者Ｃａ２＋处理果实在后熟过程中,ＣａＭ含量均发生变化,与此同时,伴随着多聚半乳糖醛酸酶（ＰＧ）、淀粉酶（Ａｍｇｌａｓｅ）活性的变化,它们之间存在极显著的相关性。Ｃａ２＋对果实后熟具有双重效应,当Ｃａ２＋处理果实置于室温下时,ＣａＭ含量、ＰＧ、淀粉酶活性明显受到抑制,后熟延缓。但把Ｃａ２＋处理果实冷藏（１２ ｄ）后回至室温第 ３～４ ｄ时,或直接减压渗钙果肉切片,其ＣａＭ含量、ＰＧ、淀粉酶活性增加,后熟加快。外源乙烯能解除Ｃａ２＋的抑制效应。并讨论了Ｃａ２＋的这些效应的可能机制。     

几种热带水果桔小实蝇的发生与防治

桔小实蝇[Bactroceradorsalis(Hendel)]是危害热带、亚热带水果和花芽的重要检疫性害虫之一。本研究对湛江地区芒果、杨桃、番荔枝、番石榴桔小实蝇成虫的年发生动态进行了调查。结果表明,桔小实蝇成虫在上述4种水果上拥有1￣2个发生高峰期,发生高峰期基本上与果实成熟期相吻合。杨桃果园桔小实蝇诱捕量明显高于其它3个果园桔小实蝇诱捕量。室内药效试验结果表明,40%辛硫磷乳油、48%乐斯本乳油对芒果桔小实蝇幼虫的防治效果为100%。而田间药效试验结果表明,1.8%阿维菌素、30%敌百虫和2.5%功夫对番荔枝桔小实蝇的防治效果分别为91.47%,88.74%和13.28%。甲基丁香酚 敌敌畏对桔小实蝇雄性成虫具有良好的诱杀效果,水解植物蛋白对桔小实蝇雌性成虫具有一定的诱杀作用。     

Improvement of bait sprays for the control of Bactrocera oleae (Diptera: Tephritidae)

The control of the olive fruit fly Bactrocera oleae (Gmelin) is based on insecticides that are usually applied as bait sprays. Large-scale field experiments were conducted in the Kolymvari region of Crete (Greece) to evaluate the efficacy of several bait spray solutions against the fly that were applied at the recommended spraying volume per hectare (or 300 ml per treated tree), compared applications at volumes reduced by two and three fold (150 and 100 ml, respectively). The trophical attractant (hydrolysed protein at 75% w/w) that was used was mixed with alpha-cypermethrin, thiacloprid, thiacloprid + deltamethrin or dimethoate, and these formulations were tested during three successive summers (2012–2014) according to European Plant Protection Organisation (EPPO) standards. The products were alternated with one another over time in the experimental plots. The results indicated that all of the bait spraying solutions of the tested products were effective against B. oleae at all of the doses tested and resulted in significantly lower olive fly populations compared with the standard recommended dose, which was indicated by the fly catches in the nets of McPhail traps within the experimental plots. The percentages of live infestations of B. oleae were very low (<2%, except in 2013 due to a very low olive fruit yield), as was the number of applications each year, which was 6–7 and did not differ among treatments. The benefits of this concept in the management of the pest and potential future improvements of the method are discussed.     

Serotonergic Innervation of the Salivary Glands and Central Nervous System of Adult Glossina pallidipes Austen (Diptera: Glossinidae), and the Impact of the Salivary Gland Hypertrophy Virus (GpSGHV) on the Host

Using a serotonin antibody and confocal microscopy, this study reports for the first time direct serotonergic innervation of the muscle sheath covering the secretory region of the salivary glands of adult tsetse fly, Glossina pallidipes Austen. Reports to date, however, note that up until this finding, dipteran species previously studied lack a muscle sheath covering of the secretory region of the salivary glands. Direct innervation of the salivary gland muscle sheath of tsetse would facilitate rapid deployment of saliva into the host, thus delaying a host response. Our results also suggest that the neuronal and abnormal pattern seen in viral infected glands by the Glossina pallidipes salivary gland hypertrophy virus (GpSGHV) is due to a compensatory increased branching of the neurons of the salivary glands, which is associated with the increased size of the salivary glands in viral infected flies. This study shows for the first time serotonin in the cell bodies of the brain and thoracico-abdominal ganglion in adult tsetse, G. pallidipes Austen (Diptera: Glossinidae). A hypothesis is proposed as to whether innervation of the muscle sheath covering of the secretory region of the salivary glands is present in brachyceran compared with nematoceran dipterans; and, a plea is made that more research is needed to develop a blood feeding model, similar to that in the blow flies, for elucidating the various mechanisms involved in production and deployment of saliva.