Infestation Rate and Abundance of Fruit Fly Species(Diptera,Tephritidae)on Solanum aethiopicum,Solanum lycopersicum,and Capsicum spp in Eastern of the Democratic Republic of Congo

This study assessing the infestation rate of fruit fly species on Solanum aethiopicum,Solanum lycopersicum,and Capsicum spp,using incubation method,was conducted in Agricultural entomology laboratory of Research Centre in Natural Sciences(CRSN)Lwiro,at Kabare in The South Kivu Province in eastern part of the Democratic Republic of Congo.Five species of Tephritidae flies observed,i.e.Bactrocera dorsalis,B.latifrons,Dacus bivitatus,Ceratitis capitata,and Zeugodacus Cucurbitae.The highest infestation rate was observed on B.dorsalis and following C.capitata in those solanaceous chilli pepper(C.frutescens),eggplant(S.aethiopicum)and tomato(S.lycopersicum)than Z.cucurbitae,B.latifrons and D.bivittatus.However,the localities Kamakombe,Buhandahanda,Lwiro,Bishibiru have predominant in the majority of hosts in chilli pepper,eggplant and tomato.

Two new species of Ortalotrypeta Hendel(Diptera:Tephritidae:Ortalotrypetini)from China,with biological observation of the genus

Two new species of Ortalotrypeta Hendel,O.costamacula Chen&Wang,sp.nov.and O.straighta Chen&Wang,sp.nov.from Shannxi,China are described and illustrated,together with their adult habits and behaviors.The biological observation of another three species,O.gansuica,O.trypetoides,and O.ziae,are also reported here.The biological reports are the first time for the tribe Ortalotrypetini,subfamily Tachiniscinae.An updated key to the genus Ortalotrypeta is provided.

中国果实蝇属一新记录种及云南镞果实蝇亚属记述(英文)

Nine species in the subgenus Zeugodacus Hendel were known to occur in Yunnan. We add seven more species to the fauna of Yunnan. Among them, one species, Bactrocera (Zeugodacus) vultus Hardy, 1973, is reported from China for the first time. This species is redescribed in detail and its male genitalia are illustrated and described for the first time. A key to the species of the subgenus Zeugodacus from Yunnan is provided.

鄂中柑橘主产区大实蝇、小实蝇防治技术

柑橘大实蝇Tetradacus citri又名柑橘大果蝇;柑橘小实蝇Dacus dorsalis又名黄苍蝇或果蛆,双翅目Diptera实蝇科Tephritidae,是我国公布的《双边协定中涉及限定性有害生物及其他植物检疫性有害生物》中规定的危险性害虫,于上世纪六七十年代在我国开始发生,本世纪初传入湖北省荆门市,成为鄂中柑橘主产区最重要的害虫之一。荆门市域内柑橘以早熟温州蜜柑品系中的‘兴津’、‘国庆4号’、‘宫川’等品种为主。

The mating system of the true fruit fly Bactrocera tryoni and its sister species, Bactrocera neohumeralis

The frugivorous ＂true＂ fruit fly, Bactrocera tryoni （Queensland fruit fly）, is presumed to have a nonresourced-based lek mating system. This is largely untested, and contrary data exists to suggest Bactrocera tryoni may have a resource-based mating system focused on fruiting host plants. We tested the mating system ofBactrocera tryoni, and its close sibling Bactrocera neohumeralis, in large field cages using laboratory reared flies. We used observational experiments that allowed us to determine if： （i） mating pairs were aggregated or nonaggregated; （ii） mating system was resource or nonresource based; （iii） flies utilized possible landmarks （tall trees over short） as mate-rendezvous sites; and （iv） males called females from male-dominated leks. We recorded nearly 250 Bactrocera tryoni mating pairs across all experiments, revealing that： （i） mating pairs were aggregated; （ii） mating nearly always occurred in tall trees over short; （iii） mating was nonresource based; and （iv） that males and females arrived at the mate-rendezvous site together with no evidence that males preceded females. Bactrocera neohumeralis copulations were much more infrequent （only 30 mating pairs in total）, but for those pairs there was a similar preference for tall trees and no evidence of a resource-based mating system. Some aspects of Bactrocera tryoni mating behavior align with theoretical expectations of a lekking system, but others do not. Until evidence for unequivocal female choice can be provided （as predicted under a true lek）, the mating system ofBactrocera tryoni is best described as a nonresource based, aggregation system for which we also have evidence that land-marking may be involved.

Methoprene application and diet protein supplementation to male melon fly, Bactrocera cucurbitae, modifies female remating behavior

Methoprene （an analogue of juvenile hormone） application and feeding on a protein diet is known to enhance male melon fly, Bactrocera cucurbitae Coquillett （Diptera： Tephritidae）, mating success. In this study, we investigated the effect of these treatments on male B. cucurbitae＇s ability to inhibit female remating. While 14-d-old females were fed on protein diet, 6-d-old males were exposed to one of the following treatments： （i） topical application of methoprene and fed on a protein diet; （ii） no methoprene but fed on a protein diet; （iii） methoprene and sugar-fed only; and （iv） sugar-fed, 14-d-old males acted as controls. Treatments had no effect on a male＇s ability to depress the female remating receptivity in comparison to the control. Females mated with protein-deprived males showed higher remating receptivity than females first mated with protein-fed males. Methoprene and protein diet interaction had a positive effect on male mating success during the first and second mating of females. Significantly more females first mated with sugar-fed males remated with protein-fed males and females first mated with methoprene treated and protein-fed males were more likely to remate with similarly treated males. Females mating latency （time to start mating） was significantly shorter with protein-fed males, and mating duration was significantly longer with protein-fed males compared with protein-deprived males. These results are discussed in the context of methoprene and/or dietary protein as prerelease treatment of sterile males in area-wide control of melon fly integrating the sterile insect technique （SIT）.

An improved culturing method for opiine fruit fly parasitoids and its application to parasitoid monitoring in the field

Good culturing methods play an important role in the study of insect behavior and its application to pest management. Here, we describe and validate a new method for rearing the parasitoid wasp, Diachasmirnorpha kraussii, which attacks some of the world＇s worst fruit fly pests and is an internationally used biological control agent. Our method differs from standard culturing approaches by presenting adult wasps with host- infested artificial media within a ＂culturing bag,＂ which mimics a natural （fruit） oviposition substrate. In laboratory trials using wild collected D. kraussii, the culturing bag method was compared to the use of host-infested nectarines, and a commonly used laboratory method of presenting host-infested artificial media within Petri dishes. The culturing bag method proved to be a significant improvement on both methods, combining the advantages of high host survival in artificial media with parasitism levels that were the equivalent to those recorded using host-infested fruits. In our field study, culturing bags infested with the Queensland fruit fly, Bactrocera tryoni, and hung in a mixed peach and nectarine orchard proved to be effective ＂artificial fruits＂ attracting wild D. kraussii for oviposition. Significantly more adult wasps were reared from the culturing bags compared to field collected fruits. This was shown to be due to higher fruit fly larval density in the bags, as similar percentage parasitism rates were found between the culturing bags and ripe fruits. We discuss how this cheap, time-efficient method could be applied to collecting and monitoring wild D. kraussii populations in orchards, and assist in maintaining genetic variability in parasitoid laboratory cultures.

From laboratory to the field: consistent effects of experience on host location by the fruit fly parasitoid Diachasmimorpha kraussii (Hymenoptera: Braconidae)

Associative learning is well documented in Hymenopteran parasitoids, where it is thought to be an adaptive mechanism for increasing successful host location in complex environments. Based on this learning capacity, it has been suggested that providing prerelease training to parasitoids reared for inundative release may lead to a subsequent increase in their efficacy as biological control agents. Using the fruit fly parasitoid Diachasmimorpha krausii we tested this hypothesis in a series of associative learning experiments which involved the parasitoid, two host fruits (tomatoes and nectarine), and one host fly (Bactrocera ttyoni). In sequential Y-tube olfactometer studies, large field-cage studies, and then open field studies, naive wasps showed a consistent preference for nectarines over tomatoes. The preference for nectarines was retained, but not significantly increased, for wasps which had prior training exposure to nectarines. However, and again consistently at all three spatial scales, prior experience on tomatoes led to significantly increased attraction to this fruit by tomato-trained wasps, including those liberated freely in the environment. These results, showing consistency of learning at multiple spatial scales, gives confidence to the many laboratory-based learning studies which are extrapolated to the field without testing. The experiment also provides direct experimental support for the proposed practice of enhancing the quality of inundatively released parasitoids through associative learning.

Male age and strain affect ejaculate quality in the Mexican fruit fly

Aging in all organisms is inevitable. Male age can have profound effects on mating success and female reproduction, yet relatively little is known on the effects of male age on different components of the ejaculate. Furthermore, in mass-reared insects used for the Sterile Insect Technique, there are often behavioral differences between mass-reared and wild males, while differences in the ejaculate have been less studied. The ejaculate in insects is composed mainly of sperm and accessory gland proteins. Here, we studied how male age and strain affected （i） protein quantity of testes and accessory glands, （ii） the biological activity of accessory gland products injected into females, （iii） sperm viability, and （iv） sperm quantity stored by females in wild and mass-reared Anastrepha ludens （Diptera： Tephritidae）. We found lower protein content in testes of old wild males and lower sperm viability in females mated with old wild males. Females stored more sperm when mated to young wild males than with young mass-reared males. Accessory gland injections of old or young males did not inhibit female remating. Knowledge of how male age affects different ejaculate components will aid our understanding on investment of the ejaculate and possible postcopulatory consequences on female behavior.

Gut fungal community and its probiotic effect on Bactrocera dorsalis

The oriental fruit fly,Bactrocera dorsalis(Diptera:Tephritidae)is a destructive horticultural pest which causes considerable economic losses every year.A collection of microorganisms live within the B.dorsalis gut,and they are involved in its development,physiology,and behavior.However,knowledge regarding the composition and function of the gut mycobiota in B.dorsalis are still limited.Here,we comprehensively characterized the gut mycobiota in B.dorsalis across different developmental stages.High-throughput sequencing results showed a significant difference in fungal species abundance and diversity among different developmental stages of B.dorsalis.Quantitative polymerase chain reaction and culture-dependent methods showed that yeast species was the dominant group in the larval stage.We isolated 13 strains of yeast from the larval gut,and found that GF(germ-free)larvae mono-associated with strain Hanseniaspora uvarum developed faster than those mono-associated with other tested fungal strains.Supplementing the larval diet with H.uvarum fully rescued B.dorsalis development,shortened the larval developmental time,and increased adult wing lengths,as well as the body sizes and weights of both pupae and adults.Thus,our study highlights the close interactions between gut fungi,especially H.uvarum,and B.dorsalis.These findings can be applied to the sterile insect technique program to promote host development during mass insect rearing.

A new species of Celidodacus Hendel, with notes on C. coloniarum(Speiser) and C. obnubilus(Karsch)

A new species of Celidodacus Hendel, C. parafenestratus Chen & Freidberg, sp. nov. from Democratic Republic of Congo, is described and illustrated. Redescriptions and illustrations of C. coloniarum and C. obnubilus are provided, of which C. coloniarum is first recorded from Kenya. A key to all species of the genus is revised.

Wild bacterial probiotics fed to larvae of mass-reared Queensland fruit fly[Bactrocera tryoni(Froggatt)]do not impact long-term survival,mate selection,or locomotor activity

Queensland fruit fly[Bactrocera Uyoni(Froggatt),Diptera,Tephritidae]is the most devastating insect pest impacting Australian horticulture.The Sterile Insect Technique(SIT)is an important component of tephritid pest management programs.However,mass-rearing and irradiation(to render insects sterile)may reduce the fitness and performance of the insect,including the ability of sterile males to successfully compete for wild females.Manipulation of the gut microbiome,including the supplementation with bacterial probiotics shows promise for enhancing the quality of mass-reared sterile flies,however there are fewer published studies targeting the larval stage.In this study,we supplemented the larval stage of mass-reared B.tryoni with bacterial probiotics.We tested several individual bacteria that had been previously isolated and characterized from the gut of wild B.tryoni larvae including Asaia sp.,Enterobacter sp.,Lactobacillus sp.,Leuconostoc sp.We also tested a consortium of all four of these bacterial isolates.The fitness parameters tested included adult survival in field cages,laboratory mate selection of bacteria supplemented males by bacteria nonsupplemented females,and laboratory locomotor activity of adult flies.None of the bacterial probiotic treatments in the current study was significantly different to the control for field survival,mate selection or locomotor activity of adult B.Uyoni,which agree with some of the other studies regarding bacterial probiotics fed to the larval stage of tephritids.Future work is needed to determine if feeding the same,and/or other probiotics to adults,as opposed to larvae can positively impact survival,mating performance,mating competitiveness and locomotor activity of B.tryoni.The bacterial group(s)and function of bacterial species that increase fitness and competitiveness is also of interest to tephritid mass-rearing programs.