The Spatial and Temporal Variations in the Superparasitism of Diachasmimorpha longicaudata Population Lines on Different Hosts After Field Release.

Evaluating the behavior of the parasitoid Diachasmimorpha longicaudata (Ashmead) (Hymenoptera: Braconidae) in the field allows improving strategies for its release. Thus, the aim of this study was to evaluate spatial and temporal variations in the superparasitism of two populations of D. longicaudata on two fruit fly hosts after releasing them in a guava (Psidium guajava L.; cultivar 'Paluma') orchard. The two parasitoid populations used were CS and AS, which were reared on Ceratitis capitata (Wiedemann) and Anastrepha fraterculus (Wiedemann), respectively. Four releases were carried out without host choice. Host larvae were offered to the parasitoids in sentinel traps attached at varying heights on the plant, and in plants located at eight different directions and seven distances (7.0, 21.0, 35.0, 49.0, 59.4, 63.0, and 69.3 m) from the center of the parasitoid release point. The traps remained in the orchard for 24, 48, and 168 h after release. After removing the traps, they were taken to the laboratory for scar counting. The percentages of parasitism, superparasitism, mortality, and emergence of parasitoids were determined. Data were analyzed using the generalized linear mixed-effect model (GLMM). The AS females were more active, as they exerted higher parasitism and superparasitism at the first distance and 48 h after release, leaving a higher number of oviposition scars on the host A. fraterculus. Additionally, higher host mortality was observed in A. fraterculus at the closest points and the first 48 h. The highest percentage of parasitoid emergence was observed in C. capitata parasitized by AS females.

Primeiro registro de Anastrepha obliqua (Diptera: Tephritidae) e de uma relação tritrófica com parasitoides em um pomar de citros no estado do Pará, Brasil / First record of Anastrepha obliqua (Diptera: Tephritidae) and a tritrophic relation with parasitoids in a citrus orchard in Pará state, Brazil

A citricultura está crescendo no Estado do Pará, Brasil, mas faltam informações sobre as pragas conhecidas como moscas-dasfrutas e os parasitoides associados na região. Visando abordar esta lacuna no conhecimento, foram coletados frutos de laranja (Citrus sinensis), laranja var. lima (C. sinensis), lima-da-pérsia (C. limettioides), limão-cidra (C. medica) e tangerina (C. reticulata). Registramos, pela primeira vez, infestação em condições naturais de campo por Anastrepha obliqua em C. sinensis no Pará e identificamos uma tritrófica entre C. sinensis, A. obliqua e os parasitoides Opius bellus e Asobara anastrephae .

Parasitism of Diachasmimorpha longicaudata (Ashmead) on two fruit fly species / Parasitismo de Diachasmimorpha longicaudata (Ashmead) em duas espécies de moscas-das-frutas

The aim of the present study was to investigate the parasitism of two fruit fly species by different Diachasmimorpha longicaudata strains. Females of two parasitoid strains were reared on Ceratitis capitata or Anastrepha fraterculus that were conditioned in adapted containers. Individual parasitoids were offered 20 larvae for 1 h, using no-choice (20 C. capitata or 20 A. fraterculus) or free-choice (10 of each species) assays. Parasitism was verified by counting scars, and the pupae were classified as non-parasitized (no scars), parasitized (one scar), or superparasitized (multiple scars). Parasitism intensity was compared by evaluating the proportions of non-parasitized, parasitized, and superparasitized larvae. Parasitism intensity and scar frequency were analyzed as functions of host species and parasitoid strain, using chi-square tests. In the non-choice tests, females of both parasitoid strains parasitized the larvae, regardless of host species. However, when the parasitoids had a choice, they preferred to superparasitize A. fraterculus larvae, which are larger than C. capitata larvae. In addition, the female parasitoids parasitized most of the host larvae, regardless of parasitoid strain or host species. However, the frequency of non-parasitized pupae was higher when the offered host species was different from the one in which the parasitoid was reared, and the frequency of superparasitized pupae was higher when the offered host species was the same as the one in which the parasitoid was reared.(AU)

O objetivo deste trabalho foi avaliar o parasitismo de larvas de Tephritidae por duas linhagens de Diachasmimorpha ­longicaudata em duas espécies de mosca-das-frutas. Foram utilizadas fêmeas do parasitoide criadas sobre Ceratitis capitata ou Anastrepha fraterculus acondicionadas em gaiolas adaptadas. Para cada fêmea foram oferecidas 20 larvas durante 1 hora, em ensaio com chance de escolha (20 C. capitata ou 20 A. fraterculus) e sem chance de escolha (10 larvas de cada espécie). Após o parasitismo, o número de cicatrizes foi verificado e os pupários classificados como: não parasitados (ausência de cicatrizes), parasitados (presença de uma cicatriz) e superparasitados (duas ou mais cicatrizes). A intensidade de parasitismo foi avaliada por meio da proporção de larvas não parasitadas, parasitadas ou superparasitadas. As variáveis intensidade de parasitismo e frequência de cicatrizes em virtude do hospedeiro e da linhagem do parasitoide foram analisadas quanto à distribuição de frequência utilizando-se o teste qui-quadrado. No teste sem escolha, independentemente da espécie hospedeira, as fêmeas das duas linhagens parasitaram as larvas oferecidas e, quando tiveram escolha, preferiram superparasitar larvas de A. fraterculus, que são maiores que as de C. capitata. A frequência de pupários sem cicatriz foi maior quando o hospedeiro oferecido foi diferente daquele em que a fêmea foi criada. Independentemente da linhagem do parasitoide, as fêmeas parasitam a maioria das larvas hospedeiras das duas espécies, mas discriminam o hospedeiro, preferindo superparasitar a espécie na qual foi criada o hospedeiro. A. fraterculus foi o preferido para postura de fêmeas.(AU)