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The expansion of Integrated Pest Management (IPM), including biological control, has had several positive consequences for the agricultural environment and participants in the production chain. To enable successful operation and applications of biological control, production of insects used for rearing natural enemies (parasitoids and predators) must be optimized to reduce time and costs and improve production both qualitatively and quantitatively. The present study evaluated the effect of wheat varieties, the main component of artificial diets for Ephestia kuehniella, on the reproductive performance and biological parameters of this flour moth, which is used for mass production of Trichogramma spp. (Hymenoptera: Trichogrammatidae) and other parasitoids and predators. Four varieties of wheat were compared: BRS 327, BRS Marcante, BRS Parrudo, and KBR, with and without the addition of corn E. kuehniella reared on 97% BRS 327 wheat flour + 3% nutritional yeast had the best biological parameters and substitution of corn for about half of the wheat increased the number of eggs per female.

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Studies of insect feeding behavior are useful in different areas of entomology such as plant resistance, biology, and insecticide efficacy. For chewing insects, this kind of technique is well established, but for sap-sucking insects, especially tiny ones such as whiteflies, aphids, and psyllids, these tests can be laborious. Manipulation is difficult and can damage the plant, affecting the results. We describe here three types of cages for tests with small insects, one for seedlings in pots, a second for larger plants or plants in the field, and a third for caging insects on part of a leaf. These cages have been useful for different types of studies in addition to feeding behavior and can facilitate research with small phytophagous sucking insects.

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Huanglongbing (HLB), the most destructive citrus disease worldwide, was first recorded in Brazil in 2004, and since then, more than 50 million trees identified with this disease have been eliminated. The disease is managed mainly by controlling the psyllid vector Diaphorina citri Kuwayama, 1908 (Hemiptera: Liviidae). Although the presence of the insect in commercial citrus groves is low, HLB infection rates increase in areas bordering the groves. The disease is transmitted by psyllids from host citrus plants in areas outside the managed groves, such as abandoned or organic groves and residential trees, and from orange jasmine plants in urban settings. In order to provide information to support HLB control, this study evaluated the biotic and abiotic variables that affect the dynamics of D. citri populations after releases of the parasitoid wasp Tamarixia radiata (Waterston, 1922) (Hymenoptera: Eulophidae) in external sources of HLB inocula. The study was divided into two parts. After releasing the parasitoids in non-commercial areas, we determined the following: (a) the variables that significantly affected the number of nymphs collected on shoots in the same non-commercial area; (b) the variables that significantly affected the number of adult psyllids collected in a neighboring commercial citrus area. Our results indicated that the number of nymphs in external areas was affected only by the host plant and rainfall. However, periodic parasitoid releases significantly reduced the number of adult psyllids collected in the commercial area. The results indicate that the release of parasitoids in external sources of inocula has the potential to maximize actions for D. citri control, contributing to the reduction of psyllid populations in commercial areas. Consequently, this strategy may help to manage the disease infection without an increase in insecticide use.

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Helicoverpa armigera (Hübner) has attacked several economically important crops since it was first reported in Brazil in 2013. Because insecticides have been used intensively to control H. armigera, resistant populations have been detected more frequently. One alternative to insecticides is the use of biological control with egg parasitoids from the family Trichogrammatidae (Hymenoptera). The present study evaluated the use of different species and strains of these parasitoids to control H. armigera in soybean. Five strains of Trichogramma pretiosum (Riley): RV (Rio Verde, Goiás, Brazil), SO (Sorriso, Mato Grosso, Brazil), 47A (Irvine, CA, USA), PR (Colombo, Paraná, Brazil), and AN (Anhumas, São Paulo, Brazil), and Trichogrammatoidea annulata (De Santis) denominated TR, from Anhumas, were used. The following parasitoid biological parameters were evaluated: parasitism rates (%), offspring viability (%) number of parasitoids emerged per egg, egg-adult duration (days), female longevity, and offspring sex ratio. Strain RV of T. pretiosum from central Brazil performed best.

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We evaluated the potential of two parasitoids as biocontrol agents of Liriomyza sativae Blanchard in northeastern Brazil. The two species were the koinobiont larval-pupal endoparasitoid Phaedrotoma scabriventris Nixon (Braconidae) and the idiobiont larval endoparasitoid Chrysocharis vonones (Walker) (Eulophidae). The biological parameters evaluated were survivorship, parasitism, and host-feeding, at 25 and 30°C. Differences between the species were observed at 25°C, but not at 30°C. At 25°C, the total parasitism for P. scabriventris (196.1 ± 17.7) and C. vonones (176.6 ± 7.24) was similar and with higher values compared to 30°C, 102.5 ± 8.81 and 89.1 ± 5 66 parasitized larvae, respectively. However, C. vonones showed a 3.97 lower survivorship as well as higher daily parasitism (1.4-fold) and host-feeding means (1.9-fold) than the braconid at 25°C. The results indicate a potential for both natural enemies to be used as biocontrol agents of L. sativae. The differences between species detected at 25°C suggest the best conditions for the application of each parasitoid.

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The lethal and sublethal effects of 11 insecticides on the predator Ceraeochrysa cubana (Hagen) were assessed under laboratory conditions. First-instar larvae and adults ≤ 48 h old were sprayed with the highest insecticides doses allowed to control Diaphorina citri Kuwayama in the citrus crop. The survival and duration rates of the different development stages, sex ratio, pre-oviposition period, fecundity, and fertility of the insects were evaluated. In the larval bioassay, chlorpyrifos and malathion had lethal effect which none larvae survived. Azadirachtin, lambda-cyhalothrin + chlorantraniliprole, lambda-cyhalothrin + thiamethoxam, and thiamethoxam had lethal and sublethal effects that did not allow to estimate the life table parameters because the low number of couples formed. Esfenvalerate, imidacloprid WG and SC, phosmet, and pyriproxyfen had sublethal effects which were reflected in the net reproductive rate and in the intrinsic rate of natural increase. In bioassay using adults, none of the individuals survived in the chlorpyrifos, lambda-cyhalothrin + chlorantraniliprole, lambda-cyhalothrin + thiamethoxam, malathion, or thiamethoxam treatments, and the azadirachtin, esfenvalerate, imidacloprid WG and SC, phosmet, and pyriproxyfen treatments were significantly lower compared to the control. None of the insecticides was harmless to first-instar larvae and adults of C. cubana under laboratory conditions showing their potential to reduce the efficiency of this predator.

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Temperature is an important climate factor that has a direct influence on insect biology and consequently a crucial role in forecasting and integrated pest management. The mealybug Dysmicoccus brevipes (Cockerell) (Hemiptera: Pseudococcidae) is one of the most common species in Brazilian vineyards. Here, development and survival of D. brevipes on leaves of table grapes (Vitis vinifera cv. Itália) were studied at five constant temperatures (15, 20, 25, 28, and 30 ± 1°C) under laboratory conditions. We investigated the developmental time and nymphal survival, temperature thresholds, and the degree-day requirements for each life stage of D. brevipes. The developmental time for the nymphal stage ranged from 32 to 130 days with decreasing the temperature, with the temperatures of 28 and 30°C providing the shorter developmental time. Survival of the entire nymphal stage was affected by the temperature, ranging from 81% at 20°C to 1% at 15°C. The predicted upper lethal temperature was 34.5°C, while the optimal temperature was 28.6°C. The minimum threshold for total development of D. brevipes occurred at 8.2°C. Dysmicoccus brevipes required 678.4 degree-days to complete development from first-instar nymph to adult. The temperature of 30°C was the most suitable for the development of D. brevipes. The thermal thresholds estimated for D. brevipes life cycle suggest that this species can develop in different table grape-producing regions of Brazil, in a temperature range between 8 and 35°C.

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The banana moth Opogona sacchari (Bojer) (Lepidoptera: Tineidae) is a polyphagous pest that can cause serious damage, in particular to banana crops in southern Brazil. The insect is a quarantine pest in several countries, including Argentina, the main consumer market for bananas from southern Brazil. Little information is available about the biology and ecology of this moth, such as a suitable diet for laboratory rearing. In order to provide support for integrated pest management of the pest, this study furnished data for selecting two diets suitable for continuous laboratory rearing of O. sacchari, one based on dried beans, wheat germ, soy bran, brewer's yeast, and casein and another diet with wheat germ and casein as protein sources. With both diets, the viability of the egg-adult period exceeded 68%, with fertility over 338 eggs per female. A corrected biotic potential analysis gave similar values for the two diets.

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Tuta absoluta (Meyrick, 1917) is a key tomato pest in South America and, recently, in Europe and Africa. To develop efficient control methods for this pest, adequate rearing protocols are desirable. As an alternative to tomato leaves (natural diet), we evaluated four artificial diets. Biological traits including larval and pupal viability and development time, pupal weight and deformations were assessed. Additionally, the optimum container size and larval density were evaluated. The diet based on casein, wheat germ and cellulose allowed the best development of T. absoluta, showing higher viability and no negative effects on larval instars and pupal weight. The best container was a glass tube measuring Ø 1 × h 6 cm, topped with waterproof cotton, with a density of three larvae. To evaluate the suitability of this diet, T. absoluta was reared during eight generations and life-table parameters were estimated for the F1, F3, F6, and F8 generations. The total viability (egg-adult) increased over the generations, reaching 75% in the eighth generation. Based on life-table estimations no differences among generations were found. The net reproductive rate (Ro) was higher than 40, the intrinsic rate of increase (rm) ranged between 0.08 and 0.11, the finite rate of increase (λ) was 1.1, the mean generation time (T) have a maximum of 44 d and doubling time ranged from 5.89-8.32 generations. These results indicated that a diet based on casein, wheat germ and cellulose was suitable for T. absoluta rearing in laboratory conditions.

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The cotton bollworm Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) is a widespread pest of many cultivated and wild plants in Europe, Africa, Asia, and Australia. In 2013, this species was reported in Brazil, attacking various host crops in the midwestern and northeastern regions of the country and is now found countrywide. Aiming to understand the effects of different host plants on the life cycle of H. armigera, we selected seven species of host plants that mature in different seasons and are commonly grown in these regions: cotton (Gossypium hirsutum, "FM993"), corn (Zea mays, "2B587"), soybean (Glycine max, "99R01"), rattlepods (Crotalaria spectabilis), millet (Pennisetum glaucum, "ADR300"), sorghum (Sorghum bicolor, "AGROMEN70G35"), and cowpea (Vigna unguiculata, "SEMPRE VERDE"). The development time of immatures, body weight, survivorship, and fecundity of H. armigera were evaluated on each host plant under laboratory conditions. The bollworms did not survive on corn, millet, or sorghum and showed very low survival rates on rattlepods. Survival rates were highest on soybean, followed by cotton and cowpea. The values for relative fitness found on soybean, cotton, cowpea, and rattlepods were 1, 0.5, 0.43, and 0.03, respectively. Survivorship, faster development time, and fecundity on soybean, cotton, and cowpea were positively correlated. Larger pupae and greater fecundity were found on soybean and cotton. The results indicated that soybean, cotton, and cowpea are the most suitable plants to support the reproduction of H. armigera in the field.

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The use of synthetic acaricides for management of pest mites may alter the efficacy of the ectoparasitoid Tamarixia radiata (Waterston) in biological control of Diaphorina citri Kuwayama, the vector of the bacteria associated with huanglongbing (HLB) in citrus orchards. We evaluated the toxicity of 16 acaricides that are recommended for the control of citrus-pest mites to T. radiata. Acrinathrin, bifenthrin, carbosulfan, and fenpropathrin caused high acute toxicity and were considered harmful (mortality >77%) to T. radiata. Abamectin, diflubenzuron, etoxazole, fenbutatin oxide, fenpyroximate, flufenoxuron, hexythiazox, propargite, spirodiclofen, and sulfur caused low acute toxicity and affected the parasitism rate and emergence rate of adults (F1 generation), and were considered slightly harmful to T. radiata. Dicofol and pyridaben did not affect the survival and action of the ectoparasitoid, and were considered harmless. In addition to its acute toxicity, carbosulfan caused mortality higher than 25% for >30 d after application, and was considered persistent. Acrinathrin, bifenthrin, fenpropathrin, fenpyroximate, propargite, and sulfur caused mortalities over 25% until 24 d after application and were considered moderately persistent; abamectin was slightly persistent, and fenbutatin oxide was short lived. Our results suggest that most acaricides used to control pest mites in citrus affect the density and efficacy of T. radiata in the biological control of D. citri. However, further evaluations are needed in order to determine the effect of these products on this ectoparasitoid under field conditions.

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Eggs of Anagasta kuehniella (Zeller) are widely used in mass rearing of parasitoids, especially Trichogramma spp. and predators in many biological-control programs. The objective of this study was to improve the efficiency of mass rearing of A. kuehniella through determining the optimal temperature conditions for rearing, by assessing the effect of temperature during the developmental stages on the reproduction of A. kuehniella. We evaluated 1) the effect of temperature at which A. kuehniella was kept from egg to adult death, on reproduction; 2) the effect of temperature during the larval and pupal stages on oviposition; and 3) the effect of different temperatures on adults that originated from larvae kept in a constant temperature of 25°C. The results indicated that the optimal temperature range for the development of A. kuehniella is between 20-30°C, as at 30°C there was a marked decrease in viability of the egg and larval stages. The best temperature for maintaining A. kuehniella from egg to adult death is 25°C. Temperatures of 30 and 32°C lead to deformations in genitalia of males, reducing the viability of eggs, and also eggs and females from these temperatures have lower weights. The rearing temperature of immatures affects the egg-laying capacity of adults and the egg viability. The oviposition capacity of adults kept in different temperatures ranging from 18 to 32°C, after being reared in constant temperature (25°C) during the larval stages, was not affected.

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The access and benefit sharing (ABS) regulations from the Convention on Biological Diversity (CBD) for the use of natural resources became an important issue because the biodiversity of developing countries was heavily accessed and unilaterally exploited by pharmaceutical and seed companies. However, natural enemies used for biological control are living and unmodified genetic resources which cannot be patented and have been treated as resources such as drugs, seeds, or other commercial products. Consequently, the ABS requirements have limited not only the use of natural enemies but also the positive effects that scientifically supported biological control strategies have on the society, the environment, and the economy, reducing problems of pesticide residues, water and soil contamination, and non-target effects. During the last several years, the biological control scientific community has faced new and extremely complicated legislation dictated by a high and diverse number of governmental agencies at different levels, making the access to natural resources for biocontrol purposes a rocky road. Society at large should be aware of how the strict ABS regulations affect the use of natural enemies as biological resources to secure food production, food safety, and global environmental protection. We discuss in here the current difficulties derived from CBD for the exchange of natural enemies taking as example the Euro-Mediterranean region, Argentina, and Brazil to demonstrate how long and diverse are the steps to be followed to obtain the required permits for access and exportation/importation of natural enemies. We then argue that the public visibility of biocontrol strategies should be increased and their benefits highlighted in order to persuade legislators for the development of a less bureaucratic, more expedient, and more centralized regulatory frame, greatly favoring the practice and benefits of biological control. We finally propose a general framework in which ABS issues should be dealt in ways to attend the CBD, but also to make the use of natural resources for the biological control of pests to secure food production and security a possible alternative.

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Diabrotica speciosa (Germar) is an economically important pest of Neotropical cultures and represents a quarantine risk for Neartic and Paleartic Regions. Despite its agricultural importance, few studies have been done on mating behavior and chemical communication, which has delayed the development of behavioral techniques for population management, such as the use of pheromone traps. In this study, we determined 1) the age at first mating; 2) diel rhythm of matings; 3) number of matings over 7 d; 4) the sequence of D. speciosa activities during premating, mating, and postmating; 5) the duration of each activity; and 6) response to male and female conspecific volatiles in Y-tube olfactometer. The first mating occurred between the third and seventh day after adult emergence and the majority of pairs mated on the fourth day after emergence. Pairs of D. speciosa showed a daily rhythm of mating with greater sexual activity between the end of the photophase and the first half of the scotophase. During the 7 d of observation, most pairs mated only once, although 30% mated two, three, or four times. In a Y-tube olfactometer, males were attracted by virgin females as well as by the volatile compounds emitted by females. Neither males nor their volatiles were attractive to either sex. Our observation provide information about mating behavior of D. speciosa, which will be useful in future research in chemical communication, such as identification of the pheromone and development of management techniques for this species using pheromone traps.

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In order to succeed in biological control programs, not only is it crucial to understand the number of natural enemies to be released but also on how many sites per area this releasing must be performed. These variables might differ deeply among egg parasitoid species and crops worked. Therefore, these trials were carried out to evaluate the parasitism (%) in eggs of Anticarsia gemmatalis and Pseudoplusia includens after the release of different densities of the egg parasitoid Trichogramma pretiosum. Field dispersal was also studied, in order to determine appropriate recommendations for the release of this parasitoid in soybean fields. The regression analysis between parasitism (%) and densities of the parasitoid indicated a quadratic effect for both A. gemmatalis and P. includens. The maximum parasitism within 24 h after the release was reached with densities of 25.6 and 51.2 parasitoids per host egg, respectively, for the two pests. Parasitism of T. pretiosum in eggs of P. includens decreased linearly as the distance of the pest eggs from the parasitoid release sites increased. For P. includens, the mean radius of T. pretiosum action and the area of parasitoid dispersal in the soybean crop were 8.01 m and 85.18 m2, respectively. We conclude that for a successful biological control program of lepidopteran pests using T. pretiosum in soybean fields, a density of 25.6 parasitoids per host egg, divided into 117 sites per hectare, should be used.

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We studied a population of Liriomyza sativae Blanchard (Diptera: Agromyzidae) identified by morphological and molecular techniques from the semiarid region of the Brazilian northeast. The influence of temperature and relative humidity on the survival and reproductive parameters of L. sativae in cowpeas (Vigna unguiculata L. Walp.) (Fabales: Fabaceae) was evaluated. We used temperatures of 18, 20, 22, 25, 28, 30, and 32 +/- 1 degrees C (50 +/- 10% RH) and relative humidity values of 30, 50, 70, and 90 +/- 10% (25 +/- 1 degrees C) under a 14 L:10 D photoperiod. Adult longevity decreased as temperature and relative humidity increased and was greater, in general, for females. The preoviposition and oviposition periods also decreased as temperature increased, whereas relative humidity only caused reductions in the oviposition period at higher levels. Fecundity was similar in the range from 18 to 30 degrees C but decreased at 32 degrees C with respect to relative humidity; the best performances of L. sativae occurred at lower levels. The pattern of oviposition rate changed with temperature and relative humidity. Regardless of temperature and relative humidity, L. sativae laid between 75 and 92% of its eggs on the adaxial surface of the cowpea leaves. This information will be highly useful to design a leafminer production system aimed at the multiplication of natural enemies, as well as for pest management in the field.

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This study aimed to evaluate adult emergence and duration of the pupal stage of the Mediterranean fruit fly, Ceratitis capitata (Wiedemann), and emergence of the fruit fly parasitoid, Diachasmimorpha longicaudata (Ashmead), under different moisture conditions in four soil types, using soil water matric potential. Pupal stage duration in C. capitata was influenced differently for males and females. In females, only soil type affected pupal stage duration, which was longer in a clay soil. In males, pupal stage duration was individually influenced by moisture and soil type, with a reduction in pupal stage duration in a heavy clay soil and in a sandy clay, with longer duration in the clay soil. As matric potential decreased, duration of the pupal stage of C. capitata males increased, regardless of soil type. C. capitata emergence was affected by moisture, regardless of soil type, and was higher in drier soils. The emergence of D. longicaudata adults was individually influenced by soil type and moisture factors, and the number of emerged D. longicaudata adults was three times higher in sandy loam and lower in a heavy clay soil. Always, the number of emerged adults was higher at higher moisture conditions. C. capitata and D. longicaudata pupal development was affected by moisture and soil type, which may facilitate pest sampling and allow release areas for the parasitoid to be defined under field conditions.

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The lepidopterans Platynota rostrana (Walker) (Tortricidae) and Phidotricha erigens Raganot (Pyralidae) have been found frequently in citrus groves in São Paulo State in recent years. Since in Brazil, the fertility cycle of these two species is largely unknown, as are details of the damage wrought by them in crops, this research studied these aspects of the two species, which were kept under laboratory conditions (temperature 25 ± 2 °C, 70 ± 10 percent RH, 14 h photophase) and on an artificial diet. The duration of the biological cycle (egg-adult) for P. rostrana was 38.3 days and total viability was 44.0 percent; for P. erigens these values were 32.5 days and 63.6 percent, respectively. Both species showed five larval instars. Females of P. rostrana laid an average of 308 eggs, whereas those of P. erigens laid an average of 106 eggs. In both species, female pupae were heavier than males. Male and female longevity for both species was nearly 10 days. Based on the data obtained, the artificial diet produced better results in P. rostrana than in P. erigens. If these species, which have the potential to reach pest status in the citrus groves of São Paulo State, could be reared on an artificial diet, research on their control by alternative methods would be easier.

Os lepidópteros Platynota rostrana (Walker) (Tortricidae) e Phidotricha erigens Raganot (Pyralidae) têm sido constatados com freqüência nos pomares cítricos do Estado de São Paulo, nos últimos anos. O objetivo deste trabalho foi estudar a biologia das duas espécies, em condições de laboratório (temperatura 25 ± 2 °C, UR. 70 ± 10 por cento e fotofase de 14 h) em dieta artificial, elaborar uma tabela de vida de fertilidade e descrever os danos causados no campo, devido ao desconhecimento destes aspectos biológicos dos referidos insetos no Brasil. A duração do ciclo biológico (ovo-adulto) de P. rostrana foi de 38,3 dias e a viabilidade total de 44,0 por cento, enquanto para P. erigens foi de 32,5 dias e 63,6 por cento, respectivamente. Ambas as espécies apresentaram cinco ínstares e as pupas de fêmeas foram mais pesadas do que as de machos. As fêmeas de P. rostrana colocaram, em média, 308 ovos e as de P. erigens 106 ovos. A longevidade de machos e fêmeas das duas espécies foi próxima de 10 dias. Pela tabela de vida de fertilidade concluiu-se que P. rostrana tem melhor desempenho em dieta artificial que P. erigens. É possível criar estas espécies em dieta artificial, facilitando o desenvolvimento de pesquisas relacionadas ao seu controle por métodos alternativos, caso elas assumam o status de pragas nos pomares de São Paulo.

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The lepidopterans Platynota rostrana (Walker) (Tortricidae) and Phidotricha erigens Raganot (Pyralidae) have been found frequently in citrus groves in São Paulo State in recent years. Since in Brazil, the fertility cycle of these two species is largely unknown, as are details of the damage wrought by them in crops, this research studied these aspects of the two species, which were kept under laboratory conditions (temperature 25 +/- 2 degrees C, 70 +/- 10% RH, 14 h photophase) and on an artificial diet. The duration of the biological cycle (egg-adult) for P. rostrana was 38.3 days and total viability was 44.0%; for P. erigens these values were 32.5 days and 63.6%, respectively. Both species showed five larval instars. Females of P. rostrana laid an average of 308 eggs, whereas those of P. erigens laid an average of 106 eggs. In both species, female pupae were heavier than males. Male and female longevity for both species was nearly 10 days. Based on the data obtained, the artificial diet produced better results in P. rostrana than in P. erigens. If these species, which have the potential to reach pest status in the citrus groves of São Paulo State, could be reared on an artificial diet, research on their control by alternative methods would be easier.

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In this study we analyzed the impact of physical barriers of Spodoptera frugiperda (J. E. Smith) egg-masses on the behavior of Trichogramma atopovirilia Oatman & Platner and Trichogramma pretiosum Riley. The duration of drumming, drilling, oviposition, period spent over the egg-mass, and interval between parasitized eggs were timed, and the number of parasitized eggs were recorded. The presence of scales on the egg-masses caused a significant increase in the time spent by both parasitoids on each process and a decrease in the residence time over the egg-mass and in the number of parasitized eggs, with an increase in the number of egg layers. There was a significant decrease in the number of parasitized eggs in relation to egg-masses with one layer and no scales. We observed that the physical barriers in fall armyworm egg-masses changed the behavior of T. atopovirilia and T. pretiosum, affecting their parasitization capacity.

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