Body Part Selection for Size Classification of Two Trichogramma Species.

Body size is an important morphological characteristic that covaries with the quality of parasitoids and predators. Data show that the larger the organism is, the better the biological parameters and the host location by natural enemies in the field. The standard way of evaluating the size of parasitoids of the genus Trichogramma (Hymenoptera: Trichogrammatidae) is by measuring the tibia, but using only one body part to estimate the size of organisms can lead to miscalculations. In this paper, commercial Trichogramma pretiosum Riley, 1879 (Hymenoptera: Trichogrammatidae) and Trichogramma galloi Zucchi, 1988 (Hymenoptera: Trichogrammatidae) were mounted on slides for microscopy and photographed, and the photographs were used to measure their antennae, scutellum, ovipositor, tibia, and wing. Principal component analysis (PCA) and linear discriminant analysis (LDA) were performed to select the body part that best represents their size. PCA showed that all body parts represented size in a similar way, and LDA showed that the ovipositor was the most representative. We conclude that the best body parts for representing the size of the Trichogramma species studied are the wing and ovipositor, and at least two body parts are needed to detect two size groups.

Multiscale head anatomy of Megaphragma (Hymenoptera: Trichogrammatidae).

Methods of three-dimensional electron microscopy have been actively developed recently and open up great opportunities for morphological work. This approach is especially useful for studying microinsects, since it is possible to obtain complete series of high-resolution sections of a whole insect. Studies on the genus Megaphragma are especially important, since the unique phenomenon of lysis of most of the neuron nuclei was discovered in species of this genus. In this study we reveal the anatomical structure of the head of Megaphragma viggianii at all levels from organs to subcellular structures. Despite the miniature size of the body, most of the organ systems of M. viggianii retain the structural plan and complexity of organization at all levels. The set of muscles and the well-developed stomatogastric nervous system of this species correspond to those of larger insects, and there is also a well-developed tracheal system in the head of this species. Reconstructions of the head of M. viggianii at the cellular and subcellular levels were obtained, and of volumetric data were analyzed. A total of 689 nucleated cells of the head were reconstructed. The ultrastructure of M. viggianii is surprisingly complex, and the evolutionary benefits of such complexity are probably among the factors limiting the further miniaturization of parasitoid wasps.

Eriogynapyretorum (Lepidoptera, Saturniidae) parasitoid species investigated in Fujian, China.

Eriogynapyretorum Westwood is a notorious defoliator of Camphoraofficinarum Nees that causes large economic and ecological losses in planted forests. To understand the importance of suppressing the population of E.pyretorum on natural parasitoids, a four-years investigation was conducted in the field. Four egg parasitoid species Ooencyrtuskuvanae Howard, Trichogrammachionis Ishii, Telenomus sp. and Anastatusdexingensis Sheng & Wang were captured in the wild. One of these is the dominant endoparasitoid species T.chionis, which has a quicker developmental time (8.33 d), more offspring (8.39/egg) and a greater parasitism rate (89.54%). With different elevation distributions, the parasitism rates for Kriechbaumerellalongiscutellaris Qian & He, Gregopimplahimalayensis (Cameron), Theroniadepressa (Gupta) and Xanthopimplakonowi (Krieger) were 17.29%, 2.10%, 4.23% and 0.83%, respectively. Female longevity (47.75 d), offspring (13.36/pupa) and sex ratio (1.16:1) were compared in four pupal parasitoids and K.longiscutellaris was the most abundant species of E.pyretorum in Fujian Province.

Functional and Numerical Responses of Trichogramma euproctidis (Hymenoptera: Trichogrammatidae) to Helicoverpa armigera (Lepidoptera: Noctuidae) Under Laboratory Conditions.

The tomato fruitworm Helicoverpa armigera (Hübner) is regarded as a serious pest that affects a great number of field crops globally. One of the environmentally safe alternatives to the utilization of insecticides is controlling H. armigera via the release of biological control agents by employing parasitoids, e.g., trichogrammatid species. One of the desired parasitoids indigenous to southwestern Iran is Trichogramma euproctidis (Girault). To anticipate the outcomes of augmentative releases of T. euproctidis in the field, the numerical and functional responses of female T. euproctidis that parasitizes the eggs of H. armigera were determined in the laboratory. The densities of host eggs per glass tube arena (length: 10 cm, diameter: 1 cm) were 2, 4, 8, 16, 32, 64, or 128 individuals. The functional response to the eggs of H. armigera indicated Holling's type II response. The estimated handling time and attack rate from the random parasitoid equation were 0.6898 h and 0.00823 h, respectively. This indicates that, at the maximum level, each T. euproctidis was capable of parasitizing 34.79 eggs a day. At the 128 host egg density, the number of eggs laid, that is, the numerical response, ascended as the density of host eggs increased up to a maximum of 89.90 eggs per female. According to the obtained results of the present investigation, T. euproctidis can serve as an appropriate candidate for augmentative biological control of H. armigera. Nevertheless, it is necessary to conduct complementary experiments in greenhouses and open fields.

The Amazon and Its Biodiversity: a Source of Unexplored Potential Natural Enemies for Biological Control (Predators and Parasitoids).

The Amazon is an important source of natural enemies for biological control. The diversity of biocontrol agents in the Amazon is considerably higher than that in other Brazilian regions. However, few studies have focused on the bioprospecting of natural enemies in the Amazon. Furthermore, the expansion of agricultural land in recent decades has caused biodiversity loss in the region, including the loss of potential biocontrol agents, due to the replacement of native forests with cultivated areas and forest degradation. In this study, we reviewed the main groups of natural enemies in the Brazilian Legal Amazon: predatory mites (mainly Acari: Phytoseiidae), ladybirds (Coleoptera: Coccinellidae), and social wasps (Hymenoptera: Vespidae: Polistinae) and the Hymenoptera parasitoids of eggs (Trichogrammatidae) and of frugivorous larvae (Braconidae and Figitidae). The main species prospected and used in biological control are presented. The lack of knowledge and perspectives regarding these groups of natural enemies as well as the challenges of conducting research in the Amazon is discussed.

Online citizen sciences reveal natural enemies and new occurrence data of Meteorusstellatus Fujie, Shimizu & Maeto, 2021 (Hymenoptera, Braconidae, Euphorinae).

Background: Citizen science is a research approach that involves collaboration between professional scientists and non-professional volunteers. The utilisation of recent online citizen-science platforms (e.g. social networking services) has greatly revolutionised the accessibility of biodiversity data by providing opportunities for connecting professional and citizen scientists worldwide. Meteorusstellatus Fujie, Shimizu & Maeto, 2021 (Hymenoptera, Braconidae, Euphorinae) has been recorded from the Oriental Islands of Japan and known to be a gregarious endoparasitoid of two macro-sized sphingid moths of Macroglossum, Ma.passalus (Drury) and Ma.pyrrhosticta Butler. It constructs characteristic star-shaped communal cocoons, suspended by a long cable. Although M.stellatus has been reported only from the Oriental Islands of Japan, the authors recognise its occurrence and ecological data from Taiwan and the Palaearctic Island of Japan through posts on online citizen-science groups about Taiwanese Insects on Facebook and an article on a Japanese citizen-scientist's website. New information: Through collaboration between professional and citizen scientists via social media (Facebook groups) and websites, the following new biodiversity and ecological data associated with M.stellatus are provided: Meteorusstellatus is recorded for the first time from Taiwan and the Palaearctic Region (Yakushima Is., Japan).Cechetraminor (Butler, 1875), Hippotioncelerio (Linnaeus, 1758) and Macroglossumsitiene (Walker, 1856) (Lepidoptera, Sphingidae) are recorded for the first time as hosts of M.stellatus and two of which (C.minor and H.celerio) represent the first genus-level host records for M.stellatus.Mesochorus sp. (Hymenoptera, Ichneumonidae), indeterminate species of Pteromalidae and Trichogrammatidae (Hymenoptera), are recognised as hyperparasitoid wasps of M.stellatus.Parapolybiavaria (Fabricius, 1787) (Hymenoptera, Vespidae) is reported as a predator of pendulous communal cocoons of M.stellatus. The nature of suspended large-sized communal cocoons of M.stellatus and the importance and limitations of digital occurrence data and online citizen science are briefly discussed.

Trichogramma ostriniae Is More Effective Than Trichogramma dendrolimi As a Biocontrol Agent of the Asian Corn Borer, Ostrinia furnacalis.

The Asian corn borer (ACB), Ostrinia furnicalis, is a serious corn pest in south-east Asia, causing huge economic losses every year. Trichogramma dendrolimi and Trichogramma ostriniae, two egg parasitoids, have previously been identified as key biological control agents. To determine the age impact of ACB eggs on their effective biocontrol potential, herein we compared the biological parameters (i.e., number of parasitized eggs, emergence, developmental time, and sex ratio) of both parasitoids on ACB eggs of various ages (i.e., 0-4, 4-8, 8-12, 12-16, 16-24, 24-36, and 36-48 h old), respectively. Our results showed that the age of ACB eggs had a significant impact on the parasitization activity of T. dendrolimi in both choice and no-choice conditions. Trichogramma dendrolimi preferred to parasitize 0-8-h-old ACB eggs, and its parasitization dramatically declined on ACB eggs older than 8 h under choice and no-choice conditions. On the other hand, T. ostriniae showed high preference to parasitize all tested ACB egg ages. The age of ACB eggs had no significant impact on the parasitization of T. ostriniae under choice and no-choice conditions. Furthermore, the female progeny of T. dendrolimi decreased as the age of ACB increased, while no differences were found in female progeny of T. ostriniae. Trichogramma ostriniae also developed faster on each ACB egg age group in comparison with T. dendrolimi. Overall, the age of ACB eggs had a significant impact on T. dendrolimi performance, leading us to conclude that T. ostriniae is more effective than T. dendrolimi as a biocontrol agent of the ACB.

Complete mitochondrial genome of a parasitoid, Trichogramma chilonis (Hymenoptera: Chalcidoidea: Trichogrammatidae) and phylogenetic analysis.

Trichogramma chilonis is a kind of ovoid parasitic wasp, which has important application value in the biological control of pests. In this study, we sequenced and analyzed the complete mitogenome T. chilonis to compare mitogenomic structures and reconstruct phylogenetic relationships. The complete mitogenome sequence of T. chilonis is circular, 16,176 bp in size and encodes 13 protein-coding genes (PCGs), 2 ribosomal RNA genes (rRNA), 22 transfer RNA genes (tRNA), and a control region (CR). Nucleotide composition is highly biased toward A + T nucleotides (85.2%). All 13 protein-coding genes (PCGs) initiate with the standard start codon of ATN and terminate with the typical stop codon TAA/TAG. Phylogenetic analyses were performed using amino acids of 13 PCGs showed that T. chilonis is closely related to Trichogramma ostriniae.

Effect of Temperature on Life History and Parasitization Behavior of Trichogramma achaeae Nagaraja and Nagarkatti (Hym.: Trichogrammatidae).

Trichogramma achaeae Nagaraja and Nagarkatti (Hymenoptera: Trichogrammatidae) is currently used as biological control agent for several lepidopteran pests. Knowledge of thermal requirements is essential to optimize its rearing procedures and inundative releases. The biological characteristics and two-sex life table parameters of T. achaeae were determined at five constant temperatures (15, 20, 25, 30, and 35 °C) using Ephestia kuehniella Zeller (Lepidoptera: Pyralidae) eggs. T. achaeae was able to develop and survive from 15 °C to 30 °C, but not at 35 °C. Temperature significantly affected the preadult development time and adult longevity, decreasing when temperature increased from 15 °C to 30 °C. Temperature significantly altered the sex ratio, being female biased between 15 °C and 25 °C. Age-stage, two-sex life table analysis indicated that net reproductive rate (R0) was highest at 20 °C. Both the intrinsic rate of increase (r) and finite rate of increase (λ) increased with increasing temperature, while the mean generation time (T) decreased significantly. In addition, functional response of T. achaeae was studied, being significantly affected by temperature and host egg density, displaying a Holling type-I at 15 °C and a Holling type-II at 25 °C. The relevance of these results is discussed for the use of T. achaeae as biological control agent.

Between extreme simplification and ideal optimization: antennal sensilla morphology of miniaturized Megaphragma wasps (Hymenoptera: Trichogrammatidae).

One of the major trends in the evolution of parasitoid wasps is miniaturization, which has produced the smallest known insects. Megaphragma spp. (Hymenoptera: Trichogrammatidae) are smaller than some unicellular organisms, with an adult body length of the smallest only 170 µm. Their parasitoid lifestyle depends on retention of a high level of sensory reception comparable to that in parasitoid wasps that may have antennae hundreds of times larger. Antennal sensilla of males and females of Megaphragma amalphitanum and M. caribea and females of the parthenogenetic M. mymaripenne are described, including sensillum size, external morphology, and distribution. Eight different morphological types of sensilla were discovered, two of them appearing exclusively on female antennae. Two of the types, sensilla styloconica and aporous placoid sensilla, have not been described previously. Regression analyses were performed to detect and evaluate possible miniaturization trends by comparing available data for species of larger parasitoid wasps. The number of antennal sensilla was found to decrease with the body size; M. amalphitanum males have only 39 sensilla per antenna. The number of antennal sensilla types and sizes of the sensilla, however, show little to no correlation with the body size. Our findings on the effects of miniaturization on the antennal sensilla of Megaphragma provide material for discussion on the limits to the reduction of insect antenna.

First report of Trichogrammadanausicida and Trichogrammacacaeciae reared from Thaumatotibialeucotreta eggs in Israel.

The egg parasitpoids Trichogrammadanausicida (Nagaraja) and Trichogrammacacaeciae (Marchal) (Hymenoptera: Trichogrammatidae), are reported for the first time in Israel. Moreover, our discovery of T.danausicida is the first report of this parasitoid species outside of India. The occurrence of those trichogrammatids was first discovered and documented in May 2016 during a survey of egg parasitoids of the False codling moth Thaumatotibialeucotreta (Lepidoptera: Tortricidae). The field survey was conducted on castor bean fruits (Ricinuscommunis) in the Israeli central coastal plain. The identity of the parasitoids was revealed by means of sequencing a portion of the cytochrome oxidase I gene (COI) of the studied parasitoids.

Inter- and Intra-Specific Differentiation of Trichogramma (Hymenoptera: Trichogrammatidae) Species Using PCR-RFLP Targeting COI.

The identification of Trichogramma (Hymenoptera: Trichogrammatidae) species is problematic due to their small size and lack of distinct morphological characters. In this study, we combined morphological characters of the male genitalia and molecular methods using the mitochondrial cytochrome oxidase I (COI) gene as a molecular marker to identify eight species from 16 geographic populations: T. evanescens Westwood, T. cacoeciae Marchal, T. ostriniae Pang et Chen, T. chilonis Ishii, T. japonicum Ashmead, T. brassicae Bezdenko, T. bilingensis He et Pang, and T. dendrolimi Matsumura. We developed a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method targeting the mitochondrial COI to distinguish the eight Trichogramma species using three restriction enzymes. We further analyzed 109 COI fragments from 18 Trichogramma species and found that the PCR-RFLP method could distinguish both intra- and inter-specific genetic variation among most of the species using four additional restriction enzymes.

Egg Parasitoid Complex of the Corn Leafhopper, Dalbulus maidis (DeLong) (Hemiptera: Cicadellidae), in Argentina.

The corn leafhopper, Dalbulus maidis (DeLong), is the most important leafhopper pest of maize, Zea mays, in the Americas. A survey of the diversity of its egg parasitoids was carried out in northwestern Argentina. During summer from 2004 to 2007, the samples were collected, using sentinel eggs of D. maidis on corn leaves, exposed in 48 cornfields. Sixteen species belonging to four families of Chalcidoidea (Hymenoptera) were identified. Among the parasitoid groups, Trichogrammatidae was the most represented family with eight species, followed by Mymaridae with six species. The mymarid Anagrus incarnatus Haliday and the trichogrammatid Pseudoligosita longifrangiata (Viggiani) were the most abundant and frequent parasitoids. The mean percentage of parasitism of D. maidis eggs was 16.4% and varied greatly among the sites, ranging from 0 to 56.7%; generally, it was higher in Yungas and lower in Monte province sites. The species richness was higher in the localities within the Yungas, with 13 parasitoid species, of which two species were dominant, comprising 83.6% of the collected individuals. Monte was the province that showed the highest diversity index (H´ = 1.62). In addition, we present information on the distribution, known host associations of each parasitoid species and an identification key to all species of egg parasitoids of D. maidis in Argentina.

Mitochondrial genome of Megaphragma amalphitanum (Hymenoptera: Trichogrammatidae).

The mitochondrial genome of the parasitic wasp Megaphragma amalphitanum is published in this paper. The mitochondrial DNA (mtDNA) is 15 041 base pairs (bp) in length and contained 13 protein-coding genes, 2 rRNA genes and 22 tRNA genes. The overall base composition of the genome in descending order was 45.67% A, 8.71% C, 39.63% T and 5.99% G, with a significant AT bias of 85.30%.

Reflectance-based identification of parasitized host eggs and adult Trichogramma specimens.

A wide range of imaging and spectroscopy technologies is used in medical diagnostics, quality control in production systems, military applications, stress detection in agriculture, and ecological studies of both terrestrial and aquatic organisms. In this study, we hypothesized that reflectance profiling can be used to successfully classify animals that are otherwise very challenging to classify. We acquired hyperspectral images from adult specimens of the egg parasitoid genus Trichogramma (T. galloi, T. pretiosum and T. atopovirilia), which are ~1.0 mm in length. We also acquired hyperspectral images from host eggs containing developing Trichogramma instar and pupae. These obligate egg endoparasitoid species are commercially available as natural enemies of lepidopteran pests in food production systems. Because of their minute size and physical resemblance, classification is time consuming and requires a high level of technical experience. The classification of reflectance profiles was based on a combination of average reflectance and variogram parameters (describing the spatial structure of reflectance data) of reflectance values in individual spectral bands. Although variogram parameters (variogram analysis) are commonly used in large-scale spatial research (i.e. geoscience and landscape ecology), they have only recently been used in classification of high-resolution hyperspectral imaging data. The classification model of parasitized host eggs was equally successful for each of the three species and was successfully validated with independent data sets (>90% classification accuracy). The classification model of adult specimens accurately separated T. atopovirilia from the other two species, but specimens of T. galloi and T. pretiosum could not be accurately separated. Interestingly, molecular-based classification (using the DNA sequence of the internally transcribed spacer ITS2) of Trichogramma species published elsewhere corroborates the classification, as T. galloi and T. pretiosum are closely related and comparatively distant from T. atopovirilia. Our results emphasize the importance of using high-spectral and high-spatial resolution data in the classification of organism relatedness, and hyperspectral imaging may be of relevance to a wide range of commercial (i.e. producers of biocontrol agents), taxonomic and evolutionary research applications.

Dinâmica populacional de ovos e lagartas e parasitismo de ovos de curuquerê-do-algodoeiro por Trichogramma pretiosum em cultivares convencionais e transgênica de algodoeiro / Population dynamics and track of eggs and egg parasitism of cotton leafworm byTrichogramma pretiosum cultivars in transgenic and conventional cotton

A introdução de novas cultivares de algodoeiro na região Centro-Oeste do Brasil resultou em significativo aumento de produtividade, porém a utilização de técnicas inadequadas de cultivo trouxe muitos problemas a campo, como a maior incidência de pragas, doenças e plantas infestantes. Com o objetivo de estudar a dinâmica populacional de ovos e lagartas e o parasitismo natural de ovos de curuquerê-do-algodoeiro por Trichogramma pretiosum Riley (Hymenoptera: Trichogrammatidae), em diferentes estágios fenológicos de cultivares convencionais e transgênica (Bollgard I) de algodoeiro, foi realizado um experimento no período de dezembro de 2007 a abril de 2008 em Ipameri, Goiás, Brasil. O delineamento experimental foi o de blocos ao acaso, com cinco tratamentos e quatro repetições. Os tratamentos foram constituídos pelas cultivares de algodoeiro convencionais DeltaOPAL, FMX 966, FMX 993, FMX 910 e a transgênica NuOPAL. Alabama argillacea Hübner (Lepidoptera: Noctuidae) ovipositou em todas as cultivares, não se observando diferença em relação à preferência para oviposição. Em relação ao número médio de ovos de A. argillacea parasitados por T. pretiosum, também não houve diferenças entre as cultivares. Nas cultivares convencionais, lagartas pequenas, médias e grandes ocorreram a partir dos 34 dias após a emergência das plantas até o final do ciclo, enquanto na cultivar transgênica foram encontradas apenas lagartas pequenas. A cultivar NuOPAL controla lagartas de curuquerê-doalgodoeiro desde os primeiros estádios larvais, ou seja, ainda pequenas, e não interfere no parasitismo de ovos por T. pretiosum em relação as demais cultivares.

The introduction of new cotton cultivars in the Midwest region of Brazil resulted in a significant increase in productivity, but the use of inappropriate farming techniques brought many problems to field, as the higher incidence of pests, diseases and weeds. The aim of this work was to study the population dynamics of eggs and larvae of cotton leafworm and natural egg parasitism of the pest by Trichogramma pretiosum Riley (Hymenoptera: Trichogrammatidae) at different phenological stages of conventional and transgenic cultivars (Bollgard I) of cotton was carried out this experiment from December 2007 to April 2008 in Ipameri, Góias State, Brazil. The experimental design was a randomized blocks with five trataments and four replications. The treatments consisting of the conventional cotton cultivars DeltaOPAL, FMX 966, FMX 993, FMX 910 and the cultivar transgenic NuOPAL. Allabama argillacea Hübner (Lepidoptera: Noctuidae) oviposited on all cultivars, not presented differences in relation to oviposition preference. Compared to the average number of eggs of A. argillacea parasitized by T. pretiosum, there were no differences between cultivars. In conventional cultivars, small, medium and large larvae occurred from 34 days after plant emergence until the end of the cycle, while in the transgenic cultivar were found only small caterpillars. Cultivar NuOPAL control cotton leafworm since the first larval stage, and does not interfere in egg parasitism by T. pretiosum compared with other cultivars.

Interaction between Telenomus remus and Trichogramma pretiosum in the management of Spodoptera spp.

Interaction betweeen Telenomus remus and Trichogramma pretiosum in the management of Spodoptera spp. The use of egg parasitoids is a promising strategy for Integrated Pest Management (IPM), but different species of parasitoids have greater or lesser control efficiency, depending on the pest species. Recently, not only Anticarsia gemmatalis and Pseudoplusia includens but also Spodoptera cosmioides and S. eridania have been among the key Lepidoptera larvae attacking soybeans. This study evaluated the combination of Telenomus remus and Trichogramma pretiosum for parasitism of eggs of the Spodoptera complex, for better control efficiency and broader spectrum of action among the key pests of soybeans. The experiment was carried out under controlled environmental conditions (25 ± 2ºC; 70 ± 10 percent RH; and 14 h photophase) in a completely randomized experimental design with seven treatments and 10 replicates with S. frugiperda, S. cosmioides and S. eridania eggs. Each replicate consisted of one egg mass of each Spodoptera species, with approximately 100 eggs offered to the parasitoids. The treatments were: 1) 10 females of T. pretiosum; 2) nine females of T. pretiosum and one female of T. remus; 3) eight females of T. pretiosum and two females of T. remus; 4) seven females of T. pretiosum and three females of T. remus; 5) six females of T. pretiosum and four females of T. remus; 6) five females of T. pretiosum and five females of T. remus, and 7) 10 females of T. remus. The parameter evaluated was the percentage of parasitized eggs. Results showed that treatments combining both parasitoid species with only 1 T. remus for each 9 T. pretiosum (10 percent) and only 2 T. remus for each 8 T. pretiosum (20 percent) were enough to significantly increase the parasitism observed on eggs of S. cosmioides and S. frugiperda, respectively. This association of T. pretiosum and T. remus in different proportions is very promising for biological control in IPM programs because it provides wide spectrum of control.

Interação de Telenomus remus e Trichogramma pretiosum no manejo de Spodoptera spp. O uso de parasitóides de ovos é uma estratégia promissora dentro do manejo integrado de pragas (MIP), mas diferentes espécies de parasitóides têm maior ou menor eficiência dependendo da espécie praga. Recentemente, não apenas Anticarsia gemmatalis e Pseudoplusia includens, mas também Spodoptera cosmioides e S. eridania estão entre as principais larvas de Lepidoptera que estão atacando a cultura da soja. Assim, este trabalho avaliou a possibilidade do uso associado de Telenomus remus e Trichogramma pretiosum no controle de ovos do complexo Spodoptera, objetivando uma maior eficiência de parasitismo com um maior espectro de ação entre as pragas-chave desta cultura. O experimento foi conduzido em condições controladas (25 ± 2ºC; 70 ± 10 por cento e fotofase de 14 h) no delineamento inteiramente casualizado com 7 tratamentos e 10 repetições e ovos de S. frugiperda, S. cosmioides e S. eridania. Para cada repetição foi oferecida aos parasitóides uma postura de cada uma das espécies de Spodoptera, com aproximadamente 100 ovos. As diferentes proporções dos parasitóides (tratamentos) avaliadas foram: 1) dez fêmeas de T. pretiosum 2) nove fêmeas de T. pretiosum e uma fêmea de T. remus 3) oito fêmeas de T. pretiosum e duas fêmeas de T. remus 4) sete fêmeas de T. pretiosum e três fêmeas de T. remus 5) seis fêmeas de T. pretiosum e quatro fêmeas de T. remus 6) cinco fêmeas de T. pretiosum e cinco fêmeas de T. remus 7) dez fêmeas de T. remus. O parâmetro avaliado foi à porcentagem de ovos parasitados. Os resultados mostraram que tratamentos combinando ambas as espécies de parasitóides com apenas 1 T. remus para cada 9 T. pretiosum (10 por cento) e apenas 2 T. remus para cada 8 T. pretiosum (20 por cento) foram suficientes para aumentar significativamente o parasitismo observado em ovos de S. cosmioides e S. frugiperda, respectivamente. Esta associação de T. pretiosum e T. remus em diferentes proporções é bastante promissora para utilização em programas de controle biológico dentro do MIP visto que poderá fornecer um bom espectro de controle.

An aquatic microhymenopterous egg-parasitoid of Argia insipida Hagen in Selys (Odonata: Coenagrionidae) and biological observations in the Central Amazon, Brazil / Um microimenóptero aquático parasitóide de ovos de Argia insipida Hagen in Selys (Odonata: Coenagrionidae) e observações biológicas na Amazônia Central, Brazil

The tritrophic interaction Argia insipida Hagen in Selys, the Trichogrammatidae egg parasitoid Pseudoligosita longifrangiata (Viggiani) and the host plant Tonina fluviatilis (Eriocaulacea), which is a substrate for egg deposition of A.insipid, was investigated. The study locality was a stream with rapids where macrophytes such as T. fluviatilis grow. Information on aquatic egg parasitoids is scarce. This is the first record of egg parasitism of A. insipida by P. longifrangiata in Brazil, and the first record of occurrence of P. longifrangiata in the country. Parasitized and unparasitized eggs of A. insipida were observed only on leaves 0-5 cm below the water surface. The maximum number of pairs of A. insipida laying eggs in the study area was observed between 13:00h and 14:00h. Leaves of T. fluviatilis become yellowish and dry out when large numbers of eggs of A. insipida are laid on them.

Foi estudada a interação entre Argia insipida Hagen in Selys, o parasitóide de ovos Pseudoligosita longifrangiata (Viggiani) (Hymenoptera: Trichogrammatidae) e a planta Tonina fluviatilis (Eriocaulacea), utilizada como substrato de oviposição de A. insipida. O local de estudo foi um curso de água com intensa correnteza, contendo macrófitas como T. fluviatilis. As informações sobre parasitóide de ovos aquáticos são escarsas. Este é o primeiro registro do parasitismo de ovos de A. insipida por P. longifrangiata no Brazil e o primeiro registro da ocorrência de P. longifrangiata no país. Ovos de A. insipida parasitados e não-parasitados foram observados somente 0-5 cm abaixo da superfície da água. O período de maior incidência de casais de A. insipida realizando posturas foi entre 13:00h e 14:00h. As folhas de T. fluviatilis tornam-se amareladas e secam quando um grande número de ovos é inserido nas folhas.

Parasitism capacity of Trichogramma pretiosum and Trichogramma acacioi (Hym.: Trichogrammatidae) on eggs of Sitotroga cerealella (Lep.: Gelechiidae)

The objective of this work was to evaluate the parasitism capacity of Trichogramma pretiosum Riley and T. acacioi Brun, Moraes and Soares (Hymenoptera: Trichogrammatidae) in eggs of the alternative host Sitotroga cerealella (Olivier) (Lepidoptera: Gelechiidae) aiming to use both species in biological control programs of Nipteria panacea Tierry-Mieg (Lepidoptera: Geometridae). The parasitism rhythm and total parasitism of these parasitoid species were affected by the temperature with higher values during the first 24 h of their life. Parasitism period was longer for T. pretiosum and T. acacioi at the lowest temperature.

O objetivo deste trabalho foi estudar a capacidade de parasitismo de Trichogramma pretiosum Riley e de Trichogramma acacioi Brun, Moraes and Soares (Hymenoptera: Trichogrammatidae) em ovos do hospedeiro alternativo Sitotroga cerealella (Olivier) (Lepidoptera: Gelechiidae), visando o uso desses inimigos naturais em programas de controle biológico da praga do abacateiro Nipteria panacea Tierry-Mieg (Lepidoptera: Geometridae). O ritmo de parasitismo de T. acacioi e T. pretiosum variou com a temperatura, sendo maior nas primeiras 24 horas de vida desses parasitóides. Além disso, o período de parasitismo foi maior para essas duas espécies de parasitóides na menor temperatura, enquanto o parasitismo total por fêmea variou com a temperatura.

Tabela de vida de fertilidade de Trichogramma pratissolii Querino & Zucchi, 2003 (Hymenoptera: Trichogrammatidae) em hospedeiros alternativos, sob diferentes temperaturas / Fertility life table of Trichogramma pratissolii Querino & Zucchi, 2003 (Hymenoptera: Trichogrammatidae) in alternative hosts, under different temperatures

A espécie, Trichogramma pratissolii Querino & Zucchi (Hymenoptera: Trichogrammatidae) foi recentemente coletada em plantios de abacate, Persea americana Mill. (Lauraceae), e pode representar uma alternativa no controle biológico de lepidópteros pragas dessa cultura. Assim, objetivou-se neste trabalho avaliar o desempenho de T. pratissolii criado em ovos de Anagasta kuehniella (Zeller) (Lepidoptera: Pyralidae) e Corcyra cephalonica (Stainton) (Lepidoptera: Pyralidae),sob diferentes temperaturas utilizando tabelas de vida de fertilidade. A criação de A. kuehniella foi mantida com dieta à base de farinha de trigo integral, milho e levedura de cerveja, enquanto para C. cephalonica foi utilizada dieta à base de farelo de arroz, levedura de cerveja e açúcar. T. pratissolii foi criado nos hospedeiros, utilizando-se a técnica de colagem de ovos em cartolina azul. Foram determinadas a duração média da geração (T), taxa líquida de reprodução (Ro), razão infinitesimal de aumento (r m) e razão infinita de aumento (λ) para as temperaturas de 15; 21; 24; 27; 30 e 33 ±1ºC, com 70±10 por cento de umidade relativa e fotofase de 14 horas. A melhor condição térmica para desenvolvimento de T. pratissolii em A. kuehniella e C. cephalonica foi a 27ºC, enquanto o melhor hospedeiro nessa temperatura é C. cephalonica.

The specie, Trichogramma pratissolii Querino & Zucchi (Hymenoptera: Trichogrammatidae) was recently collected in avocado plantations, Persea americana Mill. (Lauraceae), and therefore might be an alternative biological control agent for lepidopteran pests in this crop. Thus, this work evaluated the performance of T. pratissolii parasitizing eggs of Anagasta kuehniella Zeller (Lepidoptera: Pyralidae) and Corcyra cephalonica Stainton (Lepidoptera: Pyralidae), under different temperature regimes through fertility life table method. The host A. kuehniella was reared using diet constituted of whole wheat meal, corn meal and yeast, while C. cephalonica was reared with rice meal, yeast and sugar. Eggs of both hosts were offered to T. pratissolii pasted in blue cards. Mean generation time (T), net reproductive rate (Ro), intrinsic rate of population increase (r m) and finite rate of increase (λ) were estimated for parasitoid reared under 15; 21; 24; 27; 30 and 33 ±1ºC, 70±10 percent relative humidity and 14 hours of photoperiod. The best thermal conditions to T. pratissolii develop parasitizing A. kuehniella and C. cephalonica was 27ºC, and under this temperature eggs of the later host produced the better results.