Anastrepha Fraterculus Research Articles

Effect of Exposure Time and Ratio of Hosts to Female Parasitoids on Offspring Production ofDiachasmimorpha longicaudata(Hymneoptera: Braconidae) Reared onAnastrepha fraterculus(Diptera: Tephritidae) Larvae

ABSTRACT Diachasmimorpha longicaudata (Ashmead) is a larval-prepupal endoparasitoid of tephritid fruit fly pests in tropical and subtropical countries. Because citrus-growing areas of northern Argentina are the most affected by Anastrepha fraterculus (Wiedemann), D. longicaudata presents as a potential candidate for augmentative releases against it. Within this context, parasitoid rearing must be focused on offspring yield optimization in order to sustain a successful massrearing process. Hence, the best ratio of A. fraterculus larva to female parasitoids and the best exposure time for achieving the greatest parasitoid yield with the highest proportion of female progeny were determined under laboratory conditions in the present study. The effect of superparasitism on the percentage of D. longicaudata emergence was also assessed. Third-instars of A. fraterculus were exposed for 30, 60, 90, and 120 min to 30 mated, 5–7 d-old parasitoid females at host/parasitoid ratios of 2:1, 4:1, 6:1, 8:1, and 10:1. Resul...

Cryptic Species of the Anastrepha fraterculus Complex (Diptera: Tephritidae): A Multivariate Approach for the Recognition of South American Morphotypes

Abstract Although a large amount of data have been published in past years on the taxonomic status of the Anastrepha fraterculus (Wiedemann) species complex, there is still a need to know how many species this complex comprises, the distribution of each one, and their distinguishing features. In this study, we assessed the morphometric variability of 32 populations from the A. fraterculus complex, located in major biogeographical areas from the Neotropics. Multivariate techniques for analysis were applied to the measurements of 21 variables referring to the mesonotum, aculeus, and wing. For the first time, our results identified the presence of seven distinct morphotypes within this species complex. According to the biogeographical areas, populations occurring in the Mesoamerican dominion (Mexico, Guatemala, and Panama) were clustered within a single natural entity labeled as the “Mexican” morphotype; whereas in the northwestern South American dominion, samples fell into three distinct groups: the “Venezuelan” morphotype with a single population from the Caribbean lowlands of Venezuela, the “Andean” morphotype from the highlands of Venezuela and Colombia, and the third group or “Peruvian” morphotype comprised the samples from the Pacific coastal lowlands of Ecuador and Peru. Three additional groups were identified from the Chacoan and Paranaense sub-regions: the morphotype “Brazilian-1” was recognized as including the Argentinean samples with most pertaining to Brazil, and widely distributed in these biogeographical areas; the morphotype “Brazilian-2” was recognized as including two samples from the state of Sao Paulo (Ilha-Bela and São Sebastião); whereas the morphotype “Brazilian-3” included a single population from Botucatu (state of Sao Paulo). Based on data published by previous authors showing genetic and karyotypic differentiation, as well as reproductive isolation, we have concluded that such morphotypes indeed represent natural groups and distinct taxonomic entities.

Random mating and reproductive compatibility among Argentinean and southern Brazilian populations of Anastrepha fraterculus (Diptera: Tephritidae)

As a prerequisite for area-wide application of the sterile insect technique in an area encompassing northern Argentina and southern Brazil, prezygotic and postzygotic reproductive compatibility among three geographically distant populations in the area was tested. In field cages, sexually mature adults of each population were found to be sexually compatible, mating duration was not affected by fly origin and there was no clear evidence of spatial partition of mating location. In the laboratory, homotypic and heterotypic crosses for all possible combinations displayed similar levels of fertility and yielded F1 adults without distortion of the sex ratio. Finally, F1 hybrid and parental adults produced equally viable F2 eggs. Put together, our results and those from earlier studies suggest that a large area, ranging from Buenos Aires to the surroundings of São Paulo, could be managed using a single A. fraterculus mass-reared strain. At the northern margin of this area, two A. fraterculus morphotypes appear to coexist in sympatry. We delineate future research to further delimit the distribution of the aff1 morphotype (Argentina-southern Brazil) and to gain insight into evolutionary patterns producing divergence and radiation of tropical fruit fly species.

Moscas frugívoras e seus parasitoides nos municípios de Pelotas e Capão do Leão, Rio Grande do Sul, Brasil

As moscas frugívoras (Tephritoidea) são as principais pragas da fruticultura de clima temperado no Brasil. O objetivo do presente trabalho foi avaliar a infestação desses dípteros e a ocorrência de seus parasitoides em frutíferas nos municípios de Pelotas e Capão do Leão, localizados na região Sul, nas safras agrícolas de 2007/08 e 2008/09. Foram coletados frutos de araçazeiro-amarelo e vermelho (Psidium cattleianum Sabine, 1821), butiazeiro [Butia capitata (Mart.) Becc., 1916], caquizeiro (Diospyros kaki Linnaeus, 1753), cerejeira-do-mato (Eugenia involucrata DC., 1828), goiabeira [Psidium guajava (Linnaeus, 1753)], goiabeira-serrana [Acca sellowiana (Berg.) Burret, 1941], nespereira [Eriobotrya japonica (Thunb.) Lindley, 1822], pessegueiro [Prunus persicae (L.) Batsch, 1801], pitangueira (Eugenia uniflora Linnaeus,1753) e uvalheira (Eugenia pyriformis Cambessèdes, 1832). Os frutos foram coletados e transportados para o laboratório, onde foram individualizados e determinados os seguintes parâmetros: índice de infestação das moscas, índice de parasitismo e frequência de indivíduos por espécie de parasitoide. Foram constatadas duas espécies de Tephritidae, Anastrepha fraterculus (Wiedemann, 1830) (90,5%) e Ceratitis capitata (Wiedemann, 1824) (9,5%) e duas de Lonchaeidae, Neosilba zadolicha McAlpine & Steyskal, 1982 (87,8%) e uma espécie ainda não descrita, referida como Neosilba n. sp. 3 (12,2%). Anastrepha fraterculus é a espécie mais abundante nos dois municípios, sendo constatada na maioria das frutíferas coletadas. Caquizeiro e goiabeira foram os hospedeiros que apresentaram o maior índice de infestação por C. capitata. Quanto às espécies de Neosilba, a maior infestação ocorreu em frutos de goiabeira-serrana. Dos parasitoides emergidos, foram identificadas três espécies, sendo duas de Braconidae, Doryctobracon areolatus (Szépligeti, 1911) (52,6%) e Opius bellus (Gahan, 1930) (27,5%) e uma espécie de Figitidae, Aganaspis pelleranoi (Brèthes, 1924) (20,0%). Doryctobracon areolatus foi o parasitoide mais frequente na maioria das frutíferas amostradas, com exceção da pitangueira e cerejeira-do-mato em que predominou O. bellus, e em pessegueiro com predomínio de A. pelleranoi.

Enhancing efficacy of Mexican fruit fly SIT programmes by large‐scale incorporation of methoprene into pre‐release diet

AbstractThe juvenile hormone analogue, methoprene, has been documented to accelerate the development of reproductive competence and sexual signalling of Caribbean (Anastrepha suspensa), the Mexican (Anastrepha ludens), the South American (Anastrepha fraterculus) and West Indian (Anastrepha obliqua) tephritid fruit flies. The incorporation of methoprene into sterile fly release protocols at fly emergence and handling facilities is a key step required for large‐scale application of the technology to field release strategies. The goal of our study was to develop a method to supply, in large scale, methoprene to sterile Mexican fruit flies for release in the current Sterile Insect Technique (SIT) programme in Mexico. In field cage tests, the isolation index of sterile males after treatment with methoprene was reduced, increasing the percentage of mating between laboratory sterile males and wild females. In laboratory trials, males fed a diet containing 0.05% or 0.1% methoprene mated 4‐day earlier than untreated control males. In a pilot area tested in 3500 ha to measure the impact of the sterile releases when methoprene was supplied, no adult wild flies were detected and no larvae were found after sampling more than 330 kg of fruit both in the treated and untreated blocks. Based on the results obtained in this study, we recommend the incorporation of the methoprene on adult diet to improve the Mexican fruit fly male sexual performance when release in the field, contributing to the increase in the cost‐effectiveness of the SIT programme.

Male Courtship Behavior of the South American Fruit Fly,Anastrepha fraterculus, from an Argentinean Laboratory Strain

The South American fruit fly Anastrepha fraterculus (Wiedemann) (Diptera: Tephritidae) is a pest of fruit species of warm regions of the Americas, including Argentina. Some authors claim that this taxon includes a group of cryptic species. In order to evaluate possible targets of sexual selection, it is necessary to analyze ethological aspects of male courtship and identify particular steps that strongly influence mating success. A mating test designed to evaluate behavioral differences between insects that achieve copulation (successful males) and those that did not mate (unsuccessful males) could also be relevant for the possible implementation of control programs based on sterile insect technique. Reared insects need to be evaluated periodically, since genetic drift and artificial selection associated with rearing conditions could have a detrimental effect on their ability to compete for matings in nature. In this study, courtship behavior of A. fraterculus males from a laboratory strain was analyzed for the first time through video recordings. Three components for the activities were identified: calling, wing positions, and movements. Also, the time that males spent on each step of the courtship was registered, including the last activities before attempting copulation. Data showed that mating achievement occurs relatively quickly; 65% of the successful males reached copulation within the first ten minutes after the male and female were placed together. Behavioral differences were detected between successful and unsuccessful males. The former group tended to invest more time in activities directly related with mating (Spin, Arrowhead, Attempt); however, as courtship progressed, unsuccessful males increased the time dedicated to activities not directly associated to mating (Call 0, Relax,Stationary). There was not a single sequence of activities leading to success, but the analysis of the last activities performed before mating attempts indicated that the most frequent position before successful attempts was Arrowhead, occurring in 68% of cases, whereas in unsuccessful males this position was observed only 18% of the time before mounting. Although the behavior of the strain analyzed here should be compared with that of natural populations, one would not expect to observe significant differences as compatibility and competitiveness with wild collected flies was previously shown under field cage conditions. Behavioral tests such as those applied here might be important to assess quality of mass reared strains for sterile insect technique implementation programs.

Influence ofAnastrepha fraterculus(Diptera: Tephritidae) Larval Instars on the Production ofDiachasmimorpha longicaudata(Hymneoptera: Braconidae) Progeny and their Sex Ratio

ABSTRACT The aim of this study was to determine the optimal larval age for exposing Anastrepha fraterculus (Wiedemann) to Diachasmimorpha longicaudata (Ashmead) females to maximize parasitoid female offspring production under laboratory conditions in order to develop an efficient mass-rearing process for this biocontrol agent. Five age ranges of A. fraterculus larvae were assessed: 1–3 d-old (first instar), 4–6 d-old (second instar), 7–8 d-old (early third instar), 9–10 d-old (middle third instar), and 11–12 d-old (late third instar). The number of D. longicaudata initiating ovipositor probing on a device with third instars of A. fraterculus was significantly higher than with others containing younger instars. Although female biased parasitoid offspring was recorded in all treatments using third instars as hosts, significantly more D. longicaudata females emerged from A. fraterculus pupae originated from middle and late third instars. However, the percentage of unemerged host puparia also increased signif...

Multiple mating in Anastrepha fraterculus females and its relationship with fecundity and fertility

The occurrence of female remating has been widely reported in insects and the frequency at which it occurs and the factors driving females’ remating behavior have been shown to be both species specific and variable within species. Herein, we studied the remating behavior of females from a well established laboratory colony and a wild population of the South American fruit fly, Anastrepha fraterculus (Wiedemann) (Diptera: Tephritidae), under laboratory conditions. Latency to first mating (number of days from the onset of the experiment until the first copula) was shorter for remating females than for females that did not remate. Two-day fecundity was higher for females that did remate than for monogamous females. Egg hatch was sustained after remating and was not affected by the number of times the female mated. However, when females willing to remate were prevented from doing so, percent egg hatch showed a significant drop. These results and the fact that remating occurred more often in more fecund females than in less fecund ones suggest that remating may be a response to sperm depletion. Remating frequency was similar in laboratory and wild flies, but 2-day fecundity was higher for laboratory than for wild females of similar mating status. Also, the length of the refractory period (time between first and second copulation) was longer for wild than for laboratory females. Differences between strains could be the result of artificial selection. Results are discussed from a theoretical and applied perspective in the context of direct benefits to females.

First survey of fruit fly (Diptera: Tephritidae) and parasitoid diversity among myrtaceae fruit across the state of Bahia, Brazil

The objective of this study was to evaluate the diversity of fruit fly (Diptera: Tephritidae) species that use myrtaceous fruit, particularly guava, as hosts in several localities in the state of Bahia and to determine the infestation rates, pupal viability rates, and fruit fly-parasitoid associations. Sampling of myrtaceous fruit was carried out in 24 municipalities in different regions in the state of Bahia. Four fruit fly species, Anastrepha fraterculus, Anastrepha zenildae, Anastrepha sororcula, and Ceratitis capitata were obtained from the collected fruit. Three parasitoid species (Hymenoptera: Braconidae) emerged from Anastrepha larvae/pupae, Doryctobracon areolatus, Utetes anastrephae, and Asobara anastrephae. Doryctobracon areolatus emerged from A. fraterculus, A. sororcula and A. zenildae; Utetes anastrephae emerged from A. fraterculus and A. zenildae; and Asobara anastrephae emerged from A. fraterculus. Fruit fly and myrtaceous fruit associations are reported for the first time in several municipalities in the state of Bahia. A. zenildae was found infesting Syzygium malaccense for the first time in Brazil.

Factors affecting Anastrepha fraterculus female receptivity modulation by accessory gland products

In the context of the sterile insect technique (SIT), mass-rearing and male irradiation are imperative. Post-teneral treatments such as the addition of protein in adult′s male diet and male hormonal treatment are used to improve sexual performance and to accelerate sexual maturation. In this work we investigated the effect of male accessory glands products (AGPs) on female receptivity of the South American fruit fly Anastrepha fraterculus (Wiedemann), and the effect of strain rearing history, male irradiation, male diet and hormonal treatment on AGPs. Injections of aqueous extracts of male accessory glands into the abdomen of females reduced their receptivity. The AGPs from laboratory males were more effective in inhibiting female receptivity, compared to AGPs from wild males, irrespective of females’ origin. The AGPs from fertile males were more effective than AGPs from sterile males. The AGPs from protein-fed males were more effective than AGPs from sugar-fed males. Finally, the AGPs of males treated with juvenile hormone were less effective in inhibiting female receptivity than AGPs of untreated males. We conclude that inhibition of sexual receptivity of A. fraterculus mated females is mediated by products in male accessory gland’s and the way that these products act vary widely according to the effect of extrinsic factors. We discuss the results in the perspective of the SIT application for A. fraterculus.

Management of protein intake in the fruit fly Anastrepha fraterculus

This work tested if carbohydrates and proteins ingestion is regulated in the South American fruit fly, Anastrepha fraterculus, to optimize survival and reproduction. Adult food treatments were established by providing sugar and hydrolyzed yeast in various combinations either alone or mixed at a standard 3:1 ratio (sugar:hydrolyzed yeast). Individual food consumption was assessed and related to survival patterns. The effects of adult feeding on fecundity and fertility patterns were investigated in groups of flies. Sugar consumption was the lowest in the treatment where it was provided with hydrolyzed yeast at a fixed 3:1 ratio. Consumption of hydrolyzed yeast did not differ between this treatment and the one in which this solution was complemented with one solution of sugar. It seems that a mixture of sugar and hydrolyzed yeast at a fixed ratio of 3:1, respectively, restricts extra ingestion of sugar; most probably because of negative response of the fly to overconsumption of protein. Survival was affected by the treatments, being lower in those cases where protein was at the fixed ratio. Group experiments revealed that protein restriction expanded longevity and decreased egg production. In contrast, egg production was enhanced when flies were kept continuously with a mixture of yeast and sugar plus an extra source of sugar, and this was not in detriment of survival. Our results suggest that fixed sugar-protein ratios in which protein is in excess affects fitness components such as longevity and reproduction. These findings are discussed from a theoretical and applied perspective in the context of pest control by means of the sterile insect technique.

Effects of male nutrition on sperm storage and remating behavior in wild and laboratory Anastrepha fraterculus (Diptera: Tephritidae) females

Male physiological condition can affect his ability to modulate female sexual receptivity. Thus, studying this aspect can have biological and practical implications. Here, we examine how male nutritional status affected the amount of sperm stored, remating rate and refractory period of the tephritid fruit fly Anastrepha fraterculus (Wiedemann) females. Both wild and laboratory flies were evaluated. We also examine female sperm storage patterns. Experiments were carried out by manipulating male adult diet and exposing these males to virgin females. Females mated with differently treated males were either dissected to count the amount of sperm stored or exposed to virgin males to determine remating rate and the length of the refractory period. We found that male nutritional status affected the amount of the sperm stored and the renewal of sexual receptivity in wild flies. For laboratory flies, male nutritional status affected the length of the refractory period but not the amount of sperm stored by females. In addition, we report that the ventral receptacle is not an important organ of sperm storage in this species. We conclude that male nutritional condition influences the ability to modulate female sexual receptivity, possibly through a combination of the quantity and quality of the ejaculate. From an applied perspective, providing males with an enriched diet will likely result in increased efficacy of the sterile insect technique.

Primeiro registro de Trichopria anastrephae, parasitoide de moscas-das-frutas, no Rio Grande do Sul

Existem poucas informações sobre as espécies nativas de himenópteros parasitoides de moscas-das-frutas da Região Neotropical, o que objetivou a realização do presente trabalho. Assim, coletas de goiaba (Psidium guajava L.) foram realizadas de janeiro a março de 2009 na Área Experimental em Estudos de Produção Agroecológica (AEEPA) da Universidade Federal de Pelotas, no município de Capão do Leão, Rio Grande do Sul. Os frutos foram levados ao laboratório, contados, pesados e acondicionados individualmente em potes plásticos contendo areia umedecida e telado na parte superior. Semanalmente, o substrato foi peneirado, os pupários recolhidos e acondicionados em placas de Petri com papel filtro umedecido com água destilada. Os pupários foram mantidos em sala climatizada (26±2°C, 60±10% de umidade relativa e 12h fotofase) onde foram efetuadas observações semanais para verificar a emergência de moscas e/ou parasitoides e posterior identificação das espécies. Trichopria anastrephae Lima (Hymenoptera: Diapriidae) foi obtida de pupários de Anastrepha fraterculus, com parasitismo de 5,8%.

Host exploitation and contest behavior in a generalist parasitoid partially reflect quality of distinct host species

Information use determines parasitoid adaptive behavior in general, and host specialization or fitness in specific. Information regarding host suitability could affect sex allocation behavior, host exploitation, or aggressiveness in dyadic contests. In this paper, we relate aggressiveness of the pupal parasitoid Pachycrepoideus vindemmiae (Hymenoptera: Pteromalidae) with sex allocation and host exploitation when presented with different host species. More specifically, we presented parasitoids with puparia of five different Dipteran species: Drosophila melanogaster (Drosophilidae), Musca domestica (Muscidae), Anastrepha obliqua, Anastrepha fraterculus, and Ceratitis capitata (Tephritidae). Puparia of above species greatly varied in size and volume, were parasitized to differing extent and had varying fitness implications for P. vindemmiae. Using a composite measure of selected fitness currencies (i.e., parasitism level, offspring size, longevity and sex ratio), we typified D. melanogaster and A. obliqua as ‘low quality’ hosts for P. vindemmiae while puparia of C. capitata and A. fraterculus were considered of ‘high quality’. In contest dyads, female aggressiveness and host exploitation behavior differed between host species. Wasps exhibited highest frequencies of antennal striking and rival pursuit, and high degrees of puparium mounting, antennating and probing on C. capitata. Antennal striking frequency however was equally high on ‘low quality’ hosts such as D. melanogaster and A. obliqua. This work shows that a generalist parasitoid such as P. vindemmiae assesses host quality when confronted with hosts of differing species, size or nutritional suitability and employs such to define sex allocation, host exploitation, and contest behavior. However, contest and exploitation behavior only partially indicate host quality and broader parasitoid fitness implications. This work has further implications for parasitoid mass rearing and use of P. vindemmiae for biological control of Dipteran pests.

Anastrepha ludens and Anastrepha serpentina (Diptera: Tephritidae) Do Not Infest Psidium guajava (Myrtaceae), but Anastrepha obliqua Occasionally Shares This Resource With Anastrepha striata in Nature

This study examined whether economically important fruit fly species Anastrepha ludens (Loew), Anastrepha serpentina (Wiedemann), and Anastrepha obliqua (Macquart) (Diptera: Tephritidae) may opportunistically exploit guavas, Psidium guajava L. (Myrtaceae), growing near preferred natural hosts. We collected 3,459 kg of guavas and 895 kg of other known host species [sour orange, Citrus aurantium L.; grapefruit, Citrus paradisi Macfadyen; mango, Mangifera indica L.; white sapote, Casimiroa edulis La Llave and Lex.; sapote, Pouteria sapota (Jacq.); sapodilla, Manilkara zapota L.; and wild plum, Spondias purpurea L. and Spondias mombin L.] along an altitudinal gradient over a 4-yr period (2006-2009). Plants were growing in sympatry in 23 localities where the guavas are usually infested in the state of Veracruz, M6xico. The guava samples yielded 20,341 Anastrepha spp. pupae in total (overall mean, 5.88 pupae per kg of fruit). Confirming previous reports, Anastrepha fraterculus (Wiedemann) and Anastrepha striata (Schiner) were found heavily infesting guavas in Veracruz. Importantly, although we did not find evidence that A. ludens and A. serpentina are able to attack this valuable commodity, we document for the first time in the agriculturally important state of Veracruz that P. guajava is an alternative natural host plant of A. obliqua. We recovered two fruit in the mango-growing locality of la Vibora, Tlalixcoyan, that harbored larvae of A. striata and A. obliqua. This finding has important practical implications for management of A. obliqua. Over the entire altitudinal gradient, when individual fruit infestation was examined, a dynamic pattern of species dominance was unveiled with guavas growing below 800 m above sea level mainly attacked by A. striata and a progressive replacement with increasing altitude by A. fraterculus. Interestingly, most individual fruit examined (97%) harbored a single species of fruit fly, a finding that may be taken as evidence of competitive displacement among sympatric species of fruit flies. Based on this study and previously published work by us on this topic, we conclude that literature reports indicating that A. ludens and A. serpentina infest guavas under field conditions should be questioned.

Controle de pragas e doenças, maturação e qualidade de maçãs 'imperial gala' submetidas ao ensacamento

O objetivo deste trabalho foi avaliar a eficiência de diferentes embalagens no ensacamento de maçãs para o controle de pragas e doenças, e sua influência na maturação e qualidade dos frutos, em pomar sob sistema orgânico. O experimento foi conduzido em pomar com plantas de dez anos de idade da cultivar Imperial Gala, sobre porta-enxerto 'Marubakaido', com filtro EM-9, localizado no município de São Joaquim-SC, nas safras 2007/2008 e 2008/2009. Os frutos foram ensacados, após o raleio, com embalagens plásticas transparentes microperfuradas ou de tecido não texturizado (TNT). Frutos não ensacados constituíram o tratamento-controle. Na colheita, os frutos foram avaliados quanto aos danos provocados por mosca-das-frutas (Anastrepha fraterculus), mariposa-oriental (Grapholita molesta), lagarta-enroladeira (Bonagota salubricola) e pulgão-lanígero (Eriosoma lanigerum), incidência das doenças sarna-da-macieira (Venturia inaequalis) e podridão-amarga (Colletotrichum gloeosporioides), e atributos físico-químicos de maturação e qualidade e teor de cálcio (Ca) nos frutos. O ensacamento, independentemente do tipo de material utilizado, reduziu os danos de insetos-praga, porém não foi eficiente no controle de doenças nos frutos. O ensacamento não comprometeu o desenvolvimento de coloração vermelha na casca e o teor de Ca nos frutos. De modo geral, o ensacamento antecipou o processo de maturação, caracterizado pela redução na firmeza de polpa e na textura da casca e da polpa, e pelo aumento no índice de iodoamido.

Biology and parasitic potential of Doryctobracon areolatuson Anastrepha fraterculus larvae

The objective of this work was to study the biology and parasitic potential of Doryctobracon areolatus on larvae of Anastrepha fraterculus. The egg-adult period, the sex ratio, the longevity, the pupal viability, and the parasitism rate of D. areolatus were determined in laboratory, using A. fraterculus as host. The parasitoid development from oviposition to adult emergence required 25.00±1.70 days, the sex ratio was 0.62±0.09, and the mean longevity was 16.36±3.62 days for males and 10.24±1.71 days for females. The mean parasitism rate was 53.50±8.93%, varying from 41.60 to 68.60%, which shows the potential of this parasitoid for biological control of A. fraterculus.

Host Preference byDiachasmimorpha longicaudata(Hymneoptera: Braconidae) Reared on Larvae ofAnastrepha fraterculusandCeratitis capitata(Diptera: Tephritidae)

ABSTRACT The preferences of Diachasmimorpha longicaudata (Ashmead) for larvae of Anastrepha fraterculus (Wiedemann) and Ceratitis capitata (Wiedemann) were evaluated under laboratory conditions in no-choice and dual-choice tests, based on percent parasitism, proportion of emerged parasitoids, proportion of female offspring, and number of parasitoid female visits to and ovipositor probes on the artificial oviposition device as different measures of host preference. In no-choice tests D. longicaudata females did not demonstrate a significant preference between C. capitata and A. fraterculus larvae. Nevertheless, D. longicaudata females showed a strong preference for A. fraterculus larvae in dual-choice test. Although female biased parasitoid progeny resulted in all assays, significantly more D. longicaudata female offspring emerged from A. fraterculus pupae than from C. capitata pupae. Thus, this study confirmed that both C. capitata and A. fraterculus are appropriate host for rearing D. longicaudata, but a...

Laboratory evaluation of phytosanitary products used for control of the South American fruit fly, Anastrepha fraterculus, in organic farming

The South American fruit fly, Anastrepha fraterculus (Wied.), is one of the principal pests of fruit crops in Brazil. While organic farms use several compounds to control fruit flies, such as oils, plant extracts and soaps, there is little scientific evidence of their effectiveness. Our main goal was to evaluate the phytosanitary products used in organic orchards on A. fraterculus under laboratory conditions. Four multiples (0.25×, 0.5×, 1× and 2×) of the manufacturer-recommended concentrations of Rotenat CE ® (extract of Derris spp. with rotenone 5%) (600 ml 100 l −1), Pironat ® (pyroligneous extract) (250 ml 100 l −1), Biopirol 7M ® (pyroligneous extract) (200 ml 100 l −1), Organic neem ® (neem oil 80%) (500 ml 100 l −1), Natuneem ® (neem oil – 1500 ppm of azadirachtin) (500 ml 100 l −1) and lime sulfur (20% S + 9% Ca) (5000 ml 100 l −1) were tested on A. fraterculus via ingestion and direct contact, topical application and residual application. We subsequently tested deterrence effects of the same products on oviposition. Organic Neem ®, Natuneem ®, lime sulfur, Pironat ®, and Biopirol 7M ® showed no insecticidal effect on the South American fruit fly. Only Rotenat CE ® (1200 ml 100 l −1) showed an effect (71.6% mortality) following ingestion/contact. Lime sulfur, Pironat ® and Biopirol 7M ® did not prevent oviposition of A. fraterculus on artificial fruits.

Diagnóstico da área cultivada com uva fina de mesa (Vitis vinifera L) sob cobertura plástica e do manejo de pragas

Neste trabalho, foi realizado o censo das áreas cultivadas com uvas finas de mesa sob cultivo protegido e a identificação das principais espécies de pragas e estratégias de controle empregadas pelos produtores, no município de Caxias do Sul-RS. Na safra de 2007/2008, foram identificados os produtores envolvidos com a atividade no município e através de entrevista presencial e semiestruturada ao estabelecimento produtivo, registrou-se a área cultivada e variedades. Para produtores com cultivo de áreas superiores a 2.000m² da cultivar Itália, com dois anos ou mais de produção, foi aplicado outro questionário na safra de 2008/2009 com o objetivo de levantar as informações referentes: a) espécies de insetos e ácaros-praga que danificam as uvas finas de mesa na propriedade, segundo o viticultor; b) conhecer a realidade do manejo de insetos e ácaros-praga na cultura; c) verificar os parâmetros que o produtor utiliza para a aplicação de inseticidas; d) conhecer os produtos aplicados, e e) identificar o tipo de assistência técnica recebida pelo viticultor. Foram identificados 43 produtores de uvas finas de mesa sob cultivo protegido com área total cultivada de 30,36 ha, sendo 70,31% desta área da cultivar Itália. As pragas mais importantes mencionadas pelos produtores foram tripes - Frankliniella rodeos Moulton e a mosca-das-frutas-sul-americana Anastrepha fraterculus (Wied). O manejo realizado para controle destas pragas é através da aplicação de inseticidas com os ingredientes ativos acefato e fentiona, respectivamente, com base em calendário. Os principais problemas enfrentados para implementar estratégias de manejo de pragas no cultivo são a falta de assistência técnica, a ausência de metodologias confiáveis para o monitoramento e o reduzido número de inseticidas autorizados para a cultura.