Insecticidal plants as trade opportunities and use by small vegetable producers: an example using essential oils to control Diaphania hyalinata (Lepidoptera: Crambidae).

Production and sale of botanical insecticides depend on knowing the potential opportunities for these products. Essential oils from plants secondary metabolism can control pests, especially in agricultural systems where synthetic insecticides are limited, as in organic agriculture. The objective of this study was to evaluate the toxicity of essential oils to Diaphania hyalinata (Lepidoptera: Crambidae) and to show regions with the potential to use Cinnamomum zeylanicum, Citrus sinensis, and Syzygium aromaticum in the formulation and commercialization of insecticides to control this insect. The C. zeylanicum oil was more toxic to larvae and pupae and the S. aromaticum to eggs of D. hyalinata. Essential oils are an alternative for the management of D. hyalinata. The production of pesticides from essential oils of C. zeylanicum, C. sinensis, and S. aromaticum to control D. hyalinata has high potential in America. Also, Asia, Africa, Europe, the Middle East, and Asia can extract these plants to formulate insecticide molecules for the America countries.

Anatomy and histology of the metapleural gland in the giant tropical ant Paraponera clavata (Fabricius, 1775) (Formicidae: Paraponerinae).

Ants are social insects with about 85 exocrine glands with different morphologies. The metapleural gland is exclusive to ants and its compounds have antimicrobial action, indicating a function in the defense against pathogens. Within ants, Paraponera clavata is the only living species representative of Paraponerinae. This study describes the anatomy and histology of the metapleural gland in workers of P. clavata. The metapleural gland is formed by secretory units that release secretion in a reservoir through collecting canaliculi. Secretory units are bicellular with a well-developed globular secretory cell, with 145 µm in diameter, and a duct cell forming the collecting canaliculi characterizing a class III gland. The metapleural gland is pointed out as a synapomorphy of ants. Paraponerinae constitutes one of the six subfamilies of the basal and paraphyletic Poneroide clade and knowledge of the metapleural gland morphology contribute to the understanding of evolutionary history of the basal ants' groups.

Leaf plasticity across wet and dry seasons in Croton blanchetianus (Euphorbiaceae) at a tropical dry forest.

Plant species of the Brazilian Caatinga experience seasonal wet and dry extremes, requiring seasonally different leaf characteristics for optimizing water availability. We investigated if Croton blanchetianus Baill exhibits leaf morphoanatomical traits across seasons and positioning in sunlight/natural shade. Leaves of ten 1-3 m tall plants in full sunlight and ten in natural shade were assessed in May, July (wet season), October and December (dry season) 2015 for gas exchange, leaf size, lamina and midrib cross sections (14 parameters), and chloroplast structure (5 parameters). Net photosynthesis was greater during the wet season (21.6 µm-2 s-1) compared to the dry season (5.8 µm-2 s-1) and was strongly correlated with almost all measured parameters (p < 0.01). Shaded leaves in the wet season had higher specific leaf area (19.9 m2 kg-1 in full-sun and 23.1 m2 kg-1 in shade), but in the dry season they did not differ from those in full sun (7.5 m2 kg-1 and 7.2 m2 kg-1). In the wet season, the expansion of the adaxial epidermis and mesophyll lead to larger and thicker photosynthetic area of leaves. Furthermore, chloroplast thickness, length and area were also significantly larger in full sunlight (2.1 µm, 5.1 µm, 15.2 µm2; respectively) and shaded plants (2.0 µm, 5.2 µm, 14.8 µm2; respectively) during wetter months. Croton blanchetianus exhibits seasonal plasticity in leaf structure, presumably to optimize water use efficiency during seasons of water abundance and deficit. These results suggest that the species is adaptable to the increased drought stress projected by climate change scenarios.

Imidacloprid-mediated alterations on the salivary glands of the Neotropical brown stink bug, Euschistus heros.

The management of the Neotropical brown stinkbug Euschistus heros (Hemiptera: Pentatomidae) in soybean fields has been heavily dependent on the application of neonicotinoid insecticides. Neonicotinoids act primarily by impairing the function of the nicotinic acetylcholine receptors of the nervous system. These compounds also target specific organs (e.g., salivary glands), which may potentiate their insecticidal efficacy. Here, we evaluated whether the exposure to the neonicotinoid imidacloprid would cause cytomorphological changes in the salivary glands of E. heros. First, we determined the lethal concentrations (LCs) of imidacloprid through contact and ingestion. Subsequently, the cytomorphology of the salivary glands were evaluated in insect groups that survived exposure to the LC5 (3.75 mg a.i./L), LC50 (112.5 mg a.i./L), or LC75 (375.0 mg a.i./L, equivalent to the recommended field rate) doses. Imidacloprid induced apoptosis and necrosis in the salivary gland cells according to the insecticide concentration and salivary gland region. All concentrations increased apoptosis and injured cells (e.g., vacuolization, chromatin condensation, swelling of organelles, and plasma membrane rupture) in the principal and accessory salivary glands. Individuals that survived exposure to the highest concentrations (i.e., LC5 and LC50) were more affected, and exhibited several necrotic cells on their main principal salivary glands. Collectively, our results indicate that imidacloprid exerts toxic effects on the non-target organs, such as the salivary glands, which increases the efficacy of this compound in the management of stink bug infestations.

Leaf metabolic profiles of two soybean genotypes differentially affect the survival and the digestibility of Anticarsia gemmatalis caterpillars.

Insect pests such as Anticarsia gemmatalis cause defoliation and yield losses. Soybean breeding has obtained resistant genotypes, however the mechanism remains unknown. Studies indicated the presence of deterrents compounds in the resistant genotype IAC17, and their leaf metabolite profiles were compared to the susceptible genotype UFV105, which was elicited or not by caterpillar infestation. Cluster analysis indicated a significative distinction between these profiles as well as differences in plant defense pathways. Methylquercetins were constitutively present in the largest concentrations, specifically in the IAC17. Relationship between the resistance and the levels of phytohormones jasmonic acid, abscisic acid and salicylic acid was not observed. However, 1-aminocyclopropane -1carboxylic acid levels indicated that the ethylene may be involved in the constitutive biosynthesis of bioactive compounds. Extracts were added to the diets at three different concentrations to evaluate the effect on caterpillar survival. Lowest survival rates were observed when extracts from the resistant IAC 17 were used, at the lowest concentrations. Survival rates were not higher when IAC 17 infested by caterpillars were used. On the other hand, when extracts from the susceptible were used, the survival reductions were only observed in the highest extract concentrations. These supplementations of the diet reduced the digestive capacity, agreeing with the proteolytic activities, whereas malformations of the intestinal cells were dose dependent. The inhibitory effects persisted in higher dilutions only for the IAC17. Constitutive resistance was also explained by higher levels of protease inhibition. These results can be useful to elucidate the genes and cascades controlling the resistance.

Laboratory selection, cross-resistance, and estimations of realized heritability of indoxacarb resistance in Phenacoccus solenopsis (Homoptera: Pseudococcidae).

BACKGROUND: Cotton mealybug Phenacoccus solenopsis is a pest of cotton, vegetables, ornamentals, and medicinal plants. In many parts of the world P. solenopsis has been managed by integration of cultural, mechanical, biological and chemical methods, but in Pakistan the use of insecticide sprays has resulted in the development of resistance to some insecticides. In this study indoxacarb resistance was investigated by selecting a P. solenopsis population under laboratory conditions for many generations. The cross-resistance potential of indoxacarb resistance with other chemistries and the realized heritability of indoxacarb resistance were also evaluated. RESULTS: A field population of P. solenopsis selected with indoxacarb for 27 generations had a 25 623.17-fold resistance level. The highly indoxacarb resistant population showed very high cross-resistance to spinosad and very low cross-resistance to bifenthrin and chlorpyrifos. The mean estimated h2 of resistance to indoxacarb was only 0.04. The number of generations predicted for the development of ten-fold indoxacarb resistance at a constant h2  = 0.04 against selection intensities of 10% and 95% were 346 and 36 (slope = 3.18), 237 and 25 (slope = 2.18) and 128 and 13 (slope = 1.18). However, at a constant slope = 1.18 and selection intensities of 10% and 95%, the same increase in indoxacarb resistance occurred after 128 and 13 (h2  = 0.04), 103 and 11 (h2  = 0.05), and 86 and 9 (h2  = 0.06) generations. CONCLUSION: This study revealed that P. solenopsis has a very high resistance to indoxacarb as a result of laboratory selection. Thus, resistance to this insecticide in the field may also occur. Indoxacarb resistance can be minimized by rotating it with bifenthrin and/or chlorpyrifos due to its very low cross-resistance to these insecticides and by avoiding its rotation with Spinosad, which has very high cross-resistance. © 2019 Society of Chemical Industry.

Limonene, a Chemical Compound Related to the Resistance of Eucalyptus Species to Austropuccinia psidii.

The fungus Austropuccinia psidii is a major pathogen of Eucalyptus spp. that damages mainly early-stage leaves. Resistant clones are the most widely used control measure for the rust disease caused by A. psidii. Essential oils produced in the plant-host cells are associated with resistance. However, the chemical characteristics of Eucalyptus leaves at different stages of maturity, associated with resistance or susceptibility to A. psidii, need to be determined. The aims of this study were to characterize the chemical composition of essential oils in Eucalyptus leaves at three developmental stages of clones of three E. urophylla × E. grandis hybrids that exhibit different resistance levels to rust and to identify probable resistance-related compounds from them. The rust severity following inoculation and the quantity and quality of the essential oil extracted by hydrodistillation were determined at the first, third, and fifth leaf stages of the three clones. Identification of the compounds present in the essential oil was determined by gas chromatography coupled with mass spectrometry. No rust was observed on the three leaf stages of the resistant clone or on the fifth leaf stage of the susceptible clones. Limonene was found at high percentages in essential oils from the three leaf stages of the resistant clone and at low percentages in the susceptible clones. In vitro and in vivo tests indicated that low limonene percentages stimulated A. psidii urediniospore germination and were not fungitoxic, whereas high percentages caused complete inhibition of germination and degenerative changes in fungal reproductive structures. The limonene present in Eucalyptus leaves can be considered a chemical compound related to the rust resistance of Eucalyptus spp.

Evaluation of Culex quinquefasciatus wings asymmetry after exposure of larvae to sublethal concentration of ivermectin.

The surviving insects submitted to chemical control have morphological alterations that impact on their mechanisms of resistance and their final development. Those changes are detected and measured using physical features related to symmetry, specifically named fluctuating asymmetry. This is detected when deviations from the perfect bilateral symmetry for specific morphological characteristic is influenced by genetics or environmental stress. Thus, in this paper we analyze the wing in adult of Culex quinquefasciatus (Diptera - Culicidae) after larvae exposure to ivermectin LC50. Three hundred larvae of C. quinquefasciatus were exposed to ivermectin in 1.5 µg/L (LC50) concentration during 30 min, and three hundred larvae were exposed to distilled pure water as control group. For fluctuating asymmetry, adult males and adult females were selected from each group (n = 83) from the untreated group and (n = 79) from treated group. Wings from adults of each group were mounted in glass microscope slides and coverslip in Canada's balsam and analyzed with a stereomicroscope with a video camera attached. The treatment effect on M3 + 4 was marginally significant with higher asymmetry values in the control group. The data obtained here suggest the importance of future experiments to elucidate the mechanisms associated with FA. Moreover, according to the results obtained, it may be suggested that FA is present in females in ornaments, or secondary sexual characters, as an indicator of phenotypic quality of the partners.

Proteomic analysis of the venom of the social wasp Apoica pallens (Hymenoptera: Vespidae)

ABSTRACT Wasps are a diverse group of insects that possess a sting apparatus associated with a venom gland, which is used for predation and colony defense. The biochemistry of Hymenoptera venom has been evaluated in relation to allergy and immunology, and proteomics has been shown to be a powerful tool for the identification of compounds with pharmacological potential. Data on wasps venom the of genus Apoica are scarce, so the objective of the present work was to identify the venom proteins of the eusocial wasp Apoica pallens, as a first step towards further investigation of applied uses of the venom and its protein constituents. The venom proteins were separated by two-dimensional gel electrophoresis, followed by MALDI-TOF/TOF mass spectrometry. A total of 259 spots were detected, with molecular weights from 4.9 to 141 kDa. Thirty of these proteins were identified and classified into eight functional categories: allergen, enzyme, metabolism, structural, environmental response, proteoglycan, active in DNA and RNA, and unknown function. Due to the few available proteomic data for wasp venom, many proteins could not be identified, which makes studies with proteomic analysis of Hymenoptera venom even more important.

Morphology and Morphometry of the Midgut in the Stingless Bee Friesella schrottkyi (Hymenoptera: Apidae).

Friesella schrottkyi is a small stingless bee (3-mm long) important for agricultural and native forest pollination. This study describes the morphology and morphometry of the midgut in F. schrottkyi forager workers. The F. schrottkyi midgut presents a single-layered epithelium with digestive, regenerative and endocrine cells. The digestive cells are similar along the entire midgut length with a spherical nucleus, apex with long striated border, cytoplasmic granules in the apical region and well-developed basal labyrinth associated with mitochondria, suggesting they are multifunctional, synthesizing digestive enzymes and peritrophic matrix compounds and absorbing nutrients. Regenerative cells are located around the basal region organized in nests with some cells with a spherical nucleus. Phe-Met-Arg-Phe-NH2-amide (FMRFamide) positive endocrine cells are restricted to the posterior midgut region, suggesting a paracrine function in the midgut. This is the first morphological description of the F. schrottkyi midgut contributing to the comprehension of the digestive process of this bee.

Larvicidal activity of vegetable oils and esterified compounds against Culex quinquefasciatus (Diptera: Culicidae).

Control of Culex quinquefasciatus using chemical insecticides may result in the selection of resistant mosquito strains. Thus, the use of plant-derived products has been studied as alternative for the mosquito control. Fatty acid methyl esters (FAMEs) obtained by transesterification of vegetable oils may result in compounds with larvicidal potential against C. quinquefasciatus. However, little is known about the morphological, physiological or biochemical effects that these FAMEs may have on mosquito larvae. The present study reports the effects of these FAMEs in mosquito larvae. The FAMEs were obtained by transesterification of canola, corn, sunflower, and soybean oils with acid catalysis and the determination of FAMEs composition was done by gas chromatography-mass spectrometry (GC-MS). Larvae of C. quinquefasciatus were exposed to different concentrations of the vegetable oils and FAMEs. Thereby, different FAMEs showed LC50 values ranging from 42.32 to 196.27mg/L against C. quinquefasciatus larvae. The methyl ester obtained from sunflower oil showed the lowest LC50. Histology of C. quinquefasciatus larvae exposed to LC50 of FAMEs was performed and changes in the midgut and fat body morphology were identified. Therefore, larval mortality and changes in the internal organs suggested that FAMEs might be a promising new class of larvicidalcompounds. Cytotoxicity of FAMEs compounds was assessed with the HeLa human cell line and no effect was observed.

Superparasitism, immune response and optimum progeny yield in the gregarious parasitoid Palmistichus elaeisis.

BACKGROUND: The subsequent deposition of an egg clutch by a female parasitoid into a host already parasitised either by itself or a conspecific (i.e. superparasitism) is a counterintuitive adaptive strategy, particularly considering the female parasitoid's ability to recognise the parasitised hosts. Such a scenario suggests that the adaptive value of superparasitism depends on the number of clutches laid in the same host, with consequences for parasitoid progeny yield. Here, we tested whether such is the case for the gregarious parasitoid Palmistichus elaeisis and explored its underlying basis. RESULTS: Allowing female parasitoids to lay multiple egg clutches in a single melonworm host pupa, parasitoid progeny and fitness exhibited a peak or optimum at three egg clutches laid per host pupa. In addition, haemocyte count, encapsulation and melanisation decreased with the number of egg clutches laid per host pupa. DISCUSSION: An optimum number of three clutches laid per host pupa was detected for P. elaeisis. As immune response via haemocyte production, encapsulation and melanisation decreased with the number of clutches laid per host, the higher parasitoid yield and fitness observed is the likely consequence of a compromised immune response coupled with an accommodative (i.e. scramble) larval competitive strategy allowing enough resources for optimum balance of parasitoid number and quality produced. © 2017 Society of Chemical Industry.

Toxicity of squamocin on Aedes aegypti larvae, its predators and human cells.

BACKGROUND: The mosquito Aedes aegypti transmits a virus that causes diverse human diseases, and control of the vector is an important strategy to avoid disease propagation. Plants in the family Annonaceae are recognised as sources of molecules with uses in the medical and agriculture fields. Molecules of secondary metabolites of Annonaceae plants exhibit insecticidal potential against insect pests and vectors, especially acetogenins, showing high toxicity at low doses, which has encouraged research into producing new insecticide molecules. Herein, we identify an acetogenin from Annona mucosa seeds (chemical analysis) and provide the results of toxicity tests against larvae of A. aegypti (target insect) and its predators Culex bigoti and Toxorhynchites theobaldi (non-target insects) and cytotoxicity to human leukocytes. RESULTS: We identified squamocin (C37 H66 O7 ), a fatty acid with a bis-tetrahydrofuran ring. In A. aegypti, this compound caused behavioural disturbance before larval death and high mortality at low concentrations (LC50 = 0.01 µg mL-1 and LC90 = 0.11 µg mL-1 ). However, in predators and human leukocytes, squamocin showed no toxicity effect, indicating the selectivity of this molecule for non-target organisms. CONCLUSION: We identified squamocin from A. mucosa seeds, which exhibited lethal action against A. aegypti and showed selectivity for non-target insects and low cytotoxicity to human cells. © 2016 Society of Chemical Industry.

Ultrastructure of the Salivary Glands of the Stink Bug Predator Podisus distinctus.

Podisus distinctus (Hemiptera: Pentatomidae) is a zoophytophagous insect with significant potential for use as a biological control agent in agriculture and forestry because their nymphs and adults actively prey on diverse insect species. The saliva of this insect possesses active substances that cause paralysis and death of the prey. As the first step in identifying compounds of P. distinctus saliva, this study describes the ultrastructure of the salivary glands of this predator. The salivary system of P. distinctus possesses a pair of main salivary glands with a short anterior lobe, a long posterior lobe, and a pair of tubular accessory glands. The main salivary gland of P. distinctus has no associated muscles, suggesting that the saliva-release mechanism occurs with the help of certain thorax muscles. The main salivary gland epithelium has a single layer of cells (varying from cubical to columnar) with cytoplasm rich in rough endoplasmic reticulum, spherical granules of different sizes, a nucleus with a predominance of decondensed chromatin, and nucleolus. The apical cell region has a few short microvilli and the basal region has plasma membrane infoldings. The epithelium of the accessory salivary glands possesses a single-layered epithelium of cubic cells delimiting a narrow lumen. The apical cell region has a high density of microvilli and pleomorphic mitochondria, whereas the central cell region is rich in rough endoplasmic reticulum with a well-developed nucleus and decondensed chromatin. The basal cell region is characterized by the presence of several basal plasma membrane infoldings associated with mitochondria and numerous openings to the hemocoel forming large channels. The ultrastructural characteristics suggest that the main salivary glands and accessory salivary glands play a vital role in protein synthesis for saliva production and that the accessory glands are involved in transport of materials of the hemolymph.

Does Diatomaceous Earth Control Leaf-Cutter Ants (Hymenoptera: Formicidae) in the Eucalyptus Plantations?

Genus Atta includes some of the most important Formicidae leaf cutter ants which cause extensive damage to the eucalyptus plantations. Atta sexdens rubropilosa Forel, one of the chief pests in Brazilian reforestation, can restrict and reduce forest productivity by its intense and constant leaf-cutting activities on plants at all stages. Therefore, the demand for new products to control A. sexdens rubropilosa indicates the study of the utilization of the dry powder formulation of diatomaceous earth (DE) against this pest in the eucalyptus cultivars. The study was conducted using 120 colonies of A. sexdens rubropilosa in Eucalyptus grandis Hill ex. Maiden x Eucalyptus urophylla Blake (Myrtaceae) (urograndis) stand. The randomized block experimental design was used with six treatments (1, 10, 25, and 50 g/m2 of DE, 6.0 g/m2 sulfluramid bait per square meter of loose soil, and the control) with five replications, each with four colonies of this ant. Diatomaceous earth was applied to the active A. sexdens rubropilosa ant holes, and the sulfluramid bait was applied in bulk in a localized manner. The control efficacy of A. sexdens rubropilosa with DE was low, showing values similar to that of the control, and, for this reason, it cannot be used to control this ant. The bait with sulfluramid showed higher efficacy than those of the other treatments.

Three new species of Horismenus Walker (Hymenoptera: Eulophidae) associated with seed pods of Pithecellobium dulce (Fabaceae).

Horismenus abnormicaulis sp. nov., H. patensis sp. nov. and H. zuleidae sp. nov. (Hymenoptera: Eulophidae), all authored by Pikart, Costa & Hansson, are described from material obtained from seed pods of Pithecellobium dulce (Roxb.) Benth. (Fabaceae) collected in Northeastern Brazil. The seed pods were infested with larvae of Coleoptera (Chrysomelidae (Bruchinae) and Curculionidae). The associations of the Horismenus species and the beetle larvae have not been established. Morphological similarities between these new species and previously described species with host known suggest that H. patensis and H. zuleidae are primary parasitoids of Bruchinae, whereas H. abnormicaulis may act as a hyperparasitoid on other Horismenus species. The three species are compared with similar species of Horismenus.

Bioactivity of six plant extracts on adults of Demotispa neivai (Coleoptera: Chrysomelidae).

Demotispa neivai Bondar (Coleoptera: Chrysomelidae) damage oil palm fruits, which makes it necessary to develop products to control this insect. The mortality, repellency, and antifeeding effects on adults of D. neivai of six plant extracts of Azadirachta indica A. Juss. (Sapindales: Meliaceae), Ricinus communis (L.) (Malpighiaes: Euphorbiaceae), Citrus sinensis Oesbek (Sapindales: Rutaceae), Nicotiana tabacum (L.) (Slanales: Solanaceae), Capsicum annuum (L.) (Solanales: Solanaceae), and Artemisia absinthium (L.) (Asterales: Asteraceae) were determined: 1) the lethal concentration LC50-90, lethal time of D. neivai was evaluated after spraying the fruits of oil palm; 2) repellent effects of each ingredient were evaluated by calculating the index of repellency; 3) antifeeding effects with the rate of inhibition calculated between doses of 20 and 24 g/liter. The mortality of D. neivai was higher with the extracts Ci. sinensis, R. communis, N. tabacum, and Ca. annuum. The mortality of D. neivai increased in the first 72 hr in all treatments. The extracts of N. tabacum, Ca. annuum, and A. indica were more repellent to D. neivai that those of Ci. sinensis, Ar. Absinthium, and R. communis. Antifeeding effect was higher with Ci. sinensis and R. communis. The increased mortality of D. neivai by Ci. sinensis can be explained by the effect of this compound on the respiratory system of insects. Extracts of Ci. sinensis, R. communis, N. tabacum, and Ca. annuum repelled and caused mortality of D. neivai and, thus, can be used in integrate pest management programs of this pest in oil palm plantations.

Interplay between insulin signaling, juvenile hormone, and vitellogenin regulates maternal effects on polyphenism in ants.

Polyphenism is the phenomenon in which alternative phenotypes are produced by a single genotype in response to environmental cues. An extreme case is found in social insects, in which reproductive queens and sterile workers that greatly differ in morphology and behavior can arise from a single genotype. Experimental evidence for maternal effects on caste determination, the differential larval development toward the queen or worker caste, was recently documented in Pogonomyrmex seed harvester ants, in which only colonies with a hibernated queen produce new queens. However, the proximate mechanisms behind these intergenerational effects have remained elusive. We used a combination of artificial hibernation, hormonal treatments, gene expression analyses, hormone measurements, and vitellogenin quantification to investigate how the combined effect of environmental cues and hormonal signaling affects the process of caste determination in Pogonomyrmex rugosus. The results show that the interplay between insulin signaling, juvenile hormone, and vitellogenin regulates maternal effects on the production of alternative phenotypes and set vitellogenin as a likely key player in the intergenerational transmission of information. This study reveals how hibernation triggers the production of new queens in Pogonomyrmex ant colonies. More generally, it provides important information on maternal effects by showing how environmental cues experienced by one generation can translate into phenotypic variation in the next generation.

Fertility and life expectancy of a predatory stinkbug to sublethal doses of a pyrethroid.

Podisus distinctus (Heteroptera: Pentatomidae) is an important predator used in biological control of eucalypt defoliating caterpillars, exposed the insecticides. Lower doses of permethrin not affect the values of generation time (T), time necessary to double the population in number of individuals (DT) and intrinsic rate of population increase (r ( m )). Moreover, females of P. distinctus derived from nymphs treated with lower doses of permethrin were more fertile, triggering the effect hormetic in net reproductive rates (Ro). Results showed that low permethrin doses can be used alongside the predatory stinkbug in Integrated Pest Management programs.

Oogenesis pattern and type of ovariole of the parasitoid Palmistichus elaeisis (Hymenoptera: Eulophidae).

The knowledge on ovigeny in parasitoids is important for basic studies on physiology and applied biological control. The ovigeny pattern and type of ovariole of the parasitoid Palmistichus elaeisis Delvare & LaSalle (Hymenoptera: Eulophidae) were studied in newly-emerged females at seven, 14, 24 and 48 h intervals after their emergence from Tenebrio molitor L. pupae (Coleoptera: Tenebrionidae). Females of P. elaeisis presented ovaries composed by four ovarioles of the meroistic polytrophic type. The yolk accumulation and chorionogenesis in P. elaeisis were concluded 24 h after the female emergence. The 48 h-old females show a high quantity of egg ready for oviposition. These findings can help to improve the mass production of P. elaeisis and the augmentative biological control by using this natural enemy.