Frugiperda Eggs Research Articles

Release density, dispersal capacity, and optimal rearing conditions for Telenomus remus, an egg parasitoid of Spodoptera frugiperda, in maize

ABSTRACT We determined the release density, dispersal capacity, and optimal storage conditions for the parasitoid Telenomus remus Nixon to control Spodoptera frugiperda (J.E. Smith). Each of eighty plants within an 829-m2 plot were artificially infested with one S. frugiperda egg mass in a maize field. These plants were distributed evenly along four concentric squares which allowed for 14 different distances from a central release point (range 3.6–20.3 m). Egg parasitoids were released at four densities (0; 100,000; 150,000; and 200,000 adults/ha) in two vegetative maize growth stages (V4-5 and V8-9). After a 48-h exposure, egg masses were retrieved to evaluate parasitism rates. Spodoptera frugiperda egg parasitism by T. remus did not differ among the three parasitoid release densities. Egg parasitism decreased linearly with increasing distance from the release point, but this was influenced by the crop’s phenological stage. Egg parasitism was 28% higher at the older than younger growth stages, and dispersal distance and area of dispersal were 35% and 16% lower, respectively, at the older stage. In the laboratory, we evaluated the effects of six storage periods (0, 3, 6, 9, 12, and 15 days) of S. frugiperda eggs at four temperatures (5, 10, 15, and 20°C) on T. remus adult emergence. Our results showed the highest emergence when eggs were stored at 15°C for ≤9 days. Altogether, we identified important mass release and rearing parameters for augmentative biocontrol of T. remus on S. frugiperda eggs that may help reduce production and marketing costs.

Parasitism and suitability of Spodoptera frugiperda(Smith)eggs for four local Trichogramma species of northeastern China

Fall armyworm Spodoptera frugiperda(Smith)is a new invasive pest causing serious damages in China.Among egg parasitoids,Trichogramma are the dominant biological control agents that has been applied to control lepidopteran pests of crops,vegetables and forests worldwide.To evaluate the possibility and efficiency of local Trichogramma species of northeastern China on S.frugiperda eggs,we compared parasitism capabilities of Trichogramma dendrolimi Matsumura,T.ostriniae Pang&Chen,T.leucaniae Pang&Chen,and T.japonicum Ashmend under laboratory conditions.The results showed that all four Trichogramma species could accept S.frugiperda eggs and complete development successfully,but significant differences in fitness parameters were found among them.The parasitism of T.dendrolimi,T.ostriniae and T.leucaniae was higher than 80%on S.frugiperda egg masses,while only T.dendrolimi females supplied with S.frugiperda eggs performed higher parasitic number of eggs among all the tested species.Moreover,no significant differences in emergence rate and progeny female proportion among T.dendrolimi,T.ostriniae and T.leucaniae,but T.dendrolimi developed significantly faster on S.frugiperda eggs compared to other three species.Generally,T.japonicum performed poorly on S.frugiperda eggs in all aspects.The present study provides useful primary data for the application of local Trichogramma species against S.frugiperda those will invade northeastern China in future.

Parasitoid Complex of Fall Armyworm, Spodoptera frugiperda, in Ghana and Benin

The fall armyworm, Spodoptera frugiperda, a moth originating from the American continent, has recently invaded most African countries, where it is seriously threatening food security as a pest of cereals. The current management methods rely heavily on the use of synthetic insecticides but there is a need for more sustainable control methods, including biological control. Surveys were conducted in two West African countries, Ghana and Benin, to determine the native parasitoid complex and assess parasitism rates of S. frugiperda. Samples of S. frugiperda eggs and larvae were collected in maize fields located in 56 and 90 localities of Ghana and Benin, respectively, from July 2018 to July 2019. Ten species were found parasitizing the pest, including two egg parasitoids, one egg–larval, five larval and two larval–pupal parasitoids. The two most abundant parasitoids in both countries were two Braconidae: the egg-larval parasitoid Chelonus bifoveolatus and the larval parasitoid Coccygidum luteum. Parasitism rates were determined in three Ghanaian regions and averages varied from 0% to 75% between sites and from 5% to 38% between regions. These data provide an important baseline for the development of various biological control options. The two egg parasitoids, Telenomus remus and Trichogramma sp. can be used in augmentative biological control and investigations should be conducted to assess how cultural practices can enhance the action of the main parasitoids, C. luteum and Ch. bifoveolatus, in the field. Understanding the parasitoid complex of S. frugiperda in Africa is also necessary before any development of classical biological controls involving the introduction of parasitoids from the Americas.

Evaluation of Piper marginatum (Piperales: Piperaceae) Oil and Geraniol on the Embryonic Development of Spodoptera frugiperda (Lepidoptera: Noctuidae) in Comparison to Formulated Products.

Essential oils and their isolated constituents are constantly being studied for the control of insect pests. In this context, the present research reports the chemical composition of Piper marginatum (Jacq.) oil aiming to: 1) establish lethal concentrations LC30 and LC50 for this oil and the compound geraniol, 2) histologically examine the embryonic development of Spodoptera frugiperda (J.E. Smith) through light microscopy and scanning electron microscopy (SEM), as well as 3) compare the efficacy of the P. marginatum oil with that of the botanical insecticide azadirachtin, the synthetic insecticide deltamethrin, and acetone as a negative control. Semithin sections of S. frugiperda eggs revealed that the oil, geraniol, azadirachtin, and deltamethrin affected embryonic development at both concentrations. However, geraniol and the oil were more efficient because they caused more significant damage, even at lower concentrations. SEM revealed that all products altered the morphology of the eggs, modifying the structure of the chorion and making the eggs nonviable. Thus, this work demonstrates that P. marginatum oil is effective in the control of S. frugiperda because it results in embryonic damage even at the lowest concentrations.

First report of Telenomus remus parasitizing Spodoptera frugiperda and its field parasitism in southern China

The fall armyworm, Spodoptera frugiperda, is a lepidopteran pest that feeds on many economically important cereal crops such as corn, rice, sorghum, and sugarcane. Native to the Americas, it has become a serious invasive pest in Africa and Asia. Recently, this pest was found in China and has spread quickly across the country. As S. frugiperda will most likely become a major pest in China, Integrated Pest Management strategies, including biological control methods, should be developed to manage its populations. Here, we report the detection of Telenomus remus parasitizing S. frugiperda eggs in cornfields in southern China based on morphological and molecular evidence. Our preliminary surveys indicated that the parasitism rates of T. remus on S. frugiperda could reach 30% and 50% for egg masses and per egg mass, respectively. Further application of T. remus against S. frugiperda in biological control programs are discussed.

Pollen as a component of the diet of Doru luteipes (Scudder, 1876) (Dermaptera: Forficulidade).

The properties of maize pollen in the diet of Doru luteipes were determined by biological responses of the predator feeding on natural preys and artificial diet. The biological parameters of D. luteipes fed on Spodoptera frugiperda (Smith, 1797) eggs, maize pollen, Rhopalosiphum maidis (Fitch, 1856) + maize pollen and R. maidis were assessed. The effect of pollen on artificial diet on the biological variables of the predator nymphs and adults were also evaluated. Time span of nymphal development was greater for D. luteipes exclusively fed on earwigs, with the lowest rate of nymph survival. However, maize pollen plus earwigs in the diet provided the predator´s highest survival rate, whilst percentage of fertile females was double when fed on diets composed of S. frugiperda and R. maidis eggs. Development period decreased when D. luteipes nymphs consumed artificial diet plus pollen but there were high fecundity rates (number of laying/female and total egg/female) and a greater percentage of fertile females when they were fed on maize pollen.

Telenomus remus (Hymenoptera: Platygastridae) parasitism on Spodoptera frugiperda (Lepidoptera: Noctuidae) eggs: different parasitoid and host egg ages

Abstract: Release of egg parasitoids for biological control of pests is a promising technique in integrated pest management (IPM). However, there is a lack of information on the performance of parasitoid females of different ages, and specifically on the behavior of the parasitoid Telenomus remus towards pest eggs at different stages of embryonic development. Thus, the relationships between host age, parasitoid age, and parasitism by T. remus on Spodoptera frugiperda eggs were evaluated. Three separate bioassays were performed, each in a completely randomized design. In the first bioassay, T. remus females grouped by age in days (ranging from 1 to 10 days old) were offered 100 ± 20 eggs of S. frugiperda for 24 hours. In the second bioassay, 100 ± 20 eggs of S. frugiperda (24, 48 or 72 hours old) were offered to females of T. remus for 24 hours. In the third bioassay, 24, 48- and 72-hour-old host eggs of S. frugiperda were offered to T. remus females in a choice test. The variables evaluated were: number of parasitized eggs, parasitoid emergence (%), and sex ratio of progeny in bioassays 1 and 2, and the number of eggs parasitized in bioassay 3. The age of T. remus females did not affect the number of S. frugiperda eggs parasitized or emergence of the progeny. However, the sex ratio was more male-biased in the progeny of 1- and 2-day-old females compared to older wasps. In bioassay 2, the highest parasitism was observed in 24- and 48-hour-old eggs. Percentage emergence and sex ratios were not influenced by the ages of the eggs tested. Telenomus remus preferred to parasitize 24-hour-old eggs in bioassays 3. Overall, the age of T. remus females tested did not affect the parasitism of S. frugiperda eggs, but the number of eggs parasitized decreased with increasing host age.

Attraction of Chelonus insularis to host and host habitat volatiles during the search of Spodoptera frugiperda eggs

Egg parasitoids use different strategies than do larval parasitoids to locate hosts. The wasp Chelonus insularis Cresson is a key egg parasitoid of the fall armyworm (FAW), Spodoptera frugiperda (J. E. Smith), one of the main insect pests of maize (Zea mays L.). Using a Y-glass tube olfactometer, in this study we determined the roles of chemical cues from host and host habitats used by C. insularis when they search for FAW eggs. We found that C. insularis females were attracted to volatiles emitted by host egg masses, host females (i.e., sex pheromone), and maize seedlings with and without FAW eggs. The responses of the parasitoids to host and maize seedling volatiles increased after their first oviposition experience, making it possible for females to discriminate between maize seedlings with and without FAW eggs. The information generated in this study may be useful in the development of future biological control programs of S. frugiperda using C. insularis in either augmentation or conservation approaches.

Cost of Production of Telenomus remus (Hymenoptera: Platygastridae) Grown in Natural and Alternative Hosts.

The study of the technical and economic aspects of rearing natural enemies is essential for its effective use as a biological control agent in the field. The aim of this study was to determine the cost of production of the parasitoid, Telenomus remus (Nixon; Hymenoptera: Platygastridae), reared in eggs of its natural host, Spodoptera frugiperda (J. E. Smith; Lepidoptera: Noctuidae), and the alternative host, Corcyra cephalonica (Stainton; Lepidoptera: Pyralidae). The insects were reared in accordance with their respective methodologies of laboratory rearing. The cost of production of this biocontrol agent is US$ 0.0004 when reared with S. frugiperda eggs and US$ 0.0002 with C. cephalonica eggs.

Quality control ofTelenomus remus(Hymenoptera: Platygastridae) reared on the factitious hostCorcyra cephalonica(Lepidoptera: Pyralidae) for successive generations

Egg parasitoid rearing on factitious hosts is an important step to reduce costs and increase availability of the biocontrol agent but it requires quality control to achieve success in field conditions. To this end, this study evaluated the quality of Telenomus remus (Hymenoptera: Platygastridae) reared on Corcyra cephalonica (Lepidoptera: Pyralidae) for until 45 generations. In the first bioassay, we evaluated the body size of the laboratory-produced parasitoids. In the second bioassay, flight activity was examined, measuring the percentage of 'flyers', 'walkers' and 'deformed' parasitoids. The third bioassay assessed parasitism on Spodoptera frugiperda (Lepidoptera: Noctuidae) eggs. Our data indicate that the laboratory-reared parasitoid neither lost its ability to fly nor to parasitize S. frugiperda eggs. In conclusion, quality did not decrease significantly during 45 generations, and therefore rearing of T. remus on C. cephalonica as factitious host promises to be successful.

Influence of host preference, mating, and release density on the parasitism of Telenomus remus (Nixon) (Hymenoptera, Platygastridae)

We evaluated the influence of host preference, mating, and release density on Telenomus remus (Nixon, 1937) (Hymenoptera: Platygastridae) parasitizing eggs of Spodoptera frugiperda (Smith, 1797) (Lepidoptera: Noctuidae). First, we tested host preference of T. remus (free choice test) offered a choice between eggs of Corcyra cephalonica (Stainton, 1865) (Lepidoptera: Pyralidae) and S. frugiperda. Parasitism capacity and host preference (S. frugiperda) of T. remus reared on either of the two hosts did not differ. Secondly, we evaluated the influence of mating behavior of T. remus females on its parasitism. Only the offspring sex ratio differed between treatments, indicating that the species reproduces by parthenogenesis of the arrhenotoky type. Finally, we evaluated the influence of release density on T. remus parasitism. This was tested by releasing different numbers of the parasitoid per S. frugiperda egg using T. remus reared for different numbers of generations on C. cephalonica eggs. The regression analysis between percentage of parasitism and density of released T. remus females showed a quadratic effect for all tested parasitoid generations (F35, F40, and F45) with maximum parasitism from 65.07% to 71.69%. Our results allow the conclusion that (a) T. remus prefers S. frugiperda eggs, regardless of the host on which this parasitoid was reared, showing no preimaginal conditioning; (b) Mating does not affect the number of eggs parasitized by T. remus or the development of its offspring; and (c) The optimal T. remus release density when reared on C. cephalonica is between 0.133 and 0.150 females/S. frugiperda.

Size and flight ability of Telenomus remus parasitoids reared on eggs of the factitious host Corcyra cephalonica

In two independent bioassays, size and flight ability of parasitoids reared on eggs of Corcyra cephalonica for 19 generations and parasitoids reared on a natural host (Spodoptera frugiperda eggs) for 250 generations were compared as fast quality control procedures for insect rearing. The size of parasitoids was examined by morphometric analysis using a stereoscope. Length and width of the wings, right hind tibia, and the body of 20 individuals (males and females) were measured. In the analysis of flight ability, parasitoids were divided into three groups: individuals able to fly (“flyers”), individuals that did not fly but had no visible deformation (“walkers”), and individuals with visible deformation (“deformed”). We observed that parasitoids were larger when reared on the natural host than on the factitious host for all evaluated morphological characters. However, there was no significant difference between the treatments regarding the number of “flyers”, “walkers” or “deformed” parasitoids. This indicates that even though the rearing of T. remus on a factitious host affects parasitoid size, it does not necessarily affect its flight ability and therefore suggests that C. cephalonica is suitable as a factitious host for mass rearing of T. remus. Other biological parameters still need to be evaluated, such as host finding ability, parasitism capacity, and parasitoid field efficacy in order to provide a more complete picture of the effects caused by a host change. However, because fast laboratory tests are needed in rearing facilities, the one used in this study might be useful to rapidly assess parasitoid quality.

English

Factitious hosts are largely used in parasitoid production. However, changes in parasitism capacity may happen when hosts are switched. Therefore, the ability of a parasitoid species to be reared on factitious host and still keep high level of parasitism on the natural target pest after successive rearing can determine parasitoid quality and must be investigated. Thus, we evaluated Telenomus remus parasitism on Corcyra cephalonica eggs compared with its natural host, Spodoptera frugiperda eggs, for different generations. After being reared on C. cephalonica, T. remus parasitism on S. frugiperda was evaluated to measure different T. remus biological parameters and parasitism capacity (parasitoid quality). Gradual increase in C. cephalonica eggs parasitized was observed over the generations, stabilizing on generation F7. The number of parasitized C. cephalonica eggs was similar among generations (from generation F7 to F19). Taking the lifetime parasitism into consideration, parasitism capacity is similar from T. remus reared on S. frugiperda eggs from those reared on C. cephalonica eggs (generation F19). When laboratory-produced T. remus on C. cephalonica eggs was exposed to the natural host, parasitism was higher on F5 generation and stable from generations F5 to F19. Therefore, parasitoids did not lose their ability to parasitize eggs of natural host assuring good quality of the laboratory-produced parasitoid using C. cephalonica eggs as factitious host.   Key words: Spodoptera frugiperda, Corcyra cephalonica, pre-imaginal condition, egg parasitoid, biological control.

The Importance of Relative Humidity for Telenomus remus (Hymenoptera: Platygastridae) Parasitism and Development on Corcyra cephalonica (Lepidoptera: Pyralidae) and Spodoptera frugiperda (Lepidoptera: Noctuidae) Eggs

The rearing of Telenomus remus (Nixon 1937) has been limited due to the difficulty of its development in its natural host, the eggs of Spodoptera frugiperda (J.E. Smith). Environmental conditions can strongly affect egg’s parasitoid rearing on factitious hosts; however, until now only the effects of temperature have been studied. The importance of relative humidity in T. remus parasitism is poorly understood; therefore, this study evaluated its parasitism on Corcyra cephalonica (Stainton, 1866) and S. frugiperda eggs under different humidity regimes. Lifetime parasitism and parasitism viability were higher on S. frugiperda eggs and did not differ among humidity regimes. However, these biological parameters were higher at 80% humidity than at both 40 and 60% humidity when T. remus was reared on C. cephalonica eggs. The sex ratio was always higher than 0.6 for all hosts and humidity regimes. Parental female longevity was only influenced by humidity when presented to C. cephalonica eggs: it was higher at 60 and 80% humidity. T. remus egg-to-adult period was longer in C. cephalonica eggs; however, no difference between humidity regimes was noted. In general, relative humidity affected T. remus development only when it was reared on C. cephalonica eggs. For this factitious host, 80% humidity was shown to be appropriate for egg parasitoid rearing due to its better biological performance.

Telenomus remus (Hymenoptera: Platygastridae) Parasitism on Eggs of Anticarsia gemmatalis (Lepidoptera: Eribidae) Compared With Its Natural Host Spodoptera frugiperda (Lepidoptera: Noctuidae)

Abstract The capacity of Telenomus remus to parasitize eggs of Anticarsia gemmatalis, compared with its natural host, Spodoptera frugiperda, was evaluated under different temperatures. The parasitoid T. remus was reared at 25 ± 1°C for a single generation on both hosts. After reaching the adult stage, they were allowed to parasitize both hosts to study parasitoid biology and parasitism capacity at temperatures between 19°C and 37 ± 1°C. Egg-to-adult developmental time was similar on both hosts. The number of A. gemmatalis eggs parasitized was lower than that of S. frugiperda eggs at all temperatures. Parental female longevity of parasitoids was greater on A. gemmatalis eggs. This indicated a smaller metabolic expense during parasitism, acommonfeature observed on nonpreferable hosts. In general, sex ratio was little affected by temperature or hosts. When parental T. remus were reared on A. gemmatalis before the experiment, base temperature (Tb) and the thermal constant (K) were 9.53°C and 209.57 DD on eggs of A. gemmatalis and 9.68°C and 197.79 DD on eggs of S. frugiperda, respectively. When parental T. remus were reared on S. frugiperda eggs, Tb and K were 10.12°C and 188.46 DD and 9.69°C and 190.24 DD for the evaluated host eggs of A. gemmatalis and S. frugiperda, respectively. Therefore, T. remus develops in eggs of A. gemmatalis. This can be beneficial for its use in field crops where outbreaks of both Spodoptera spp. and A. gemmatalis occur. However, A. gemmatalis is a less favorable host for the parasitoid development.

<b>Population fluctuation of <i>Spodoptera frugiperda</i> eggs and natural parasitism by <i>Trichogramma</i> in maize</b> - doi: 10.4025/actasciagron.v35i3.16769

This study aimed to evaluate the fluctuation of S. frugiperda eggs and natural parasitism by Trichogramma and identify and quantify parasitoid species in maize fields in the state of Rio Grande do Sul, Brazil. Surveys were carried out in two growing seasons: in 2006/2007 we assessed one growing season (late sowing) in Santa Maria, and in 2007/2008 we assessed two growing seasons (early and late sowing) in Santa Barbara do Sul. Daily air temperature and rainfall were recorded at both locations. In each evaluation, entire plants were examined for the presence or absence of S. frugiperda egg masses, which were analyzed for larvae hatching or parasitoid emergence. The number of S. frugiperda eggs is higher between 8 and 30 days after plant emergence, decreasing in the later stages of maize growth; the occurrence of parasitoids begins about two days after pest egg occurrence; S. frugiperda egg parasitism is low; and eggs are parasitized by Trichogramma pretiosum and Trichogramma atopovirilia, with marked predominance of the first and possible occurrence of both parasitoid species in the same egg mass.

Microscopic Analysis of <I>Spodoptera frugiperda</I> (Lepidoptera: Noctuidae) Embryonic Development Before and After Treatment With Azadirachtin, Lufenuron, and Deltamethrin

The botanical insecticides, growth regulators, and pyrethroids have an effect on the biology of Spodoptera frugiperda (Smith). However, no emphasis has been given to the effect of these insecticides on embryonic development of insects, in histological level. Thus, this research aimed to examine by light and scanning electron microscopy S. frugiperda eggs and to describe the embryonic development, before and after immersion treatment, using commercial concentrations and lower concentrations than commercial ones, of the compounds lufenuron (Match), azadirachtin (AzaMax), and deltamethrin (Decis-positive control). For light microscopy semithin sections of eggs were used, and for scanning electron microscopy, images of the surface of eggs, treated and untreated with insecticides. The morphological characteristics of S. frugiperda eggs, in general, were similar to those described in the literature for most of the insects in the order Lepidoptera. Spherical eggs slightly flattened at the poles, with chorion, yolk, vitelline membrane, and embryo formation. In both microscopic analysis, we observed that insecticides acted immediately and independent of concentration, resulting absence, or incomplete embryo, presented yolk granules widely dispersed, without vitellophage formation, chorion disintegration, disorganized blastoderm, presenting vacuoles, yolk region with amorphous cells, and formation of completely uncharacterized appendages. Thus, we conclude that the compounds lufenuron and azadirachtin interfere on S. frugiperda embryonic development.

Releasing number of Telenomus remus (Nixon) (Hymenoptera: Platygastridae) against Spodoptera frugiperda Smith (Lepidoptera: Noctuidae) in corn, cotton and soybean

Telenomus remus releasing numbers may vary depending on the crop, plant architecture and/or the plant phenological stage. Thus, we examined the number of parasitoids needed for effective pest control of Spodoptera frugiperda on corn, cotton and soybean. In all crops, the parasitism response in relation to increasing numbers of the parasitoids had a quadratic effect. In corn, the maximum parasitism observed was 99.8% and 96.8% at a parasitoid releasing number of 0.231 and 0.264 T. remus females per S. frugiperda egg at phenological stages V4 and V10, respectively. Differently, in cotton and soybean, the highest parasitim were recorded using the highest tested T. remus releasing numbers (0.297 parasitoid per S. frugiperda egg). In cotton, it was 77.8% and 73.1% at the vegetative and reproductive stages, respectively and in soybean, it was 77.3% and 54.4% also at the vegetative and reproductive stages. Thus, the appropriated T. remus releasing number might vary accordingly to the crop and plant phenological stage, being higher for soybean and cotton and lower for corn.

Ar-turmerone from Curcuma longa (Zingiberaceae) rhizomes and effects on Sitophilus zeamais (Coleoptera: Curculionidae) and Spodoptera frugiperda (Lepidoptera: Noctuidae)

Turmeric, Curcuma longa L. (Zingiberaceae) has well-known insecticidal and repellent effects on insect pests, but its impact on the Maize weevil Sitophilus zeamais Motschulsky, 1855 (Coleoptera: Curculionidae) and the fall armyworm Spodoptera frugiperda J.E. Smith, 1797 (Lepidoptera: Noctuidae) is unknown. In this study, we evaluated the insecticidal and repellent effects of ar-turmerone, extracted from rhizomes of C. longa, on the S. zeamais and S. frugiperda. Individuals of S. zeamais died after six days of contact with ar-turmerone at 1% (mm−1), while individuals of S. frugiperda showed a 58% mortality rate after ingestion of this compound at 1% (mv−1). The width of head capsule, and length and weight of body of surviving S. frugiperda caterpillars exposed to ar-turmerone were 60.0, 59.6 and 93.8% lower than those of control caterpillars, respectively. Dry weight of ingested food, feces produced, weight gain and dry weight of food assimilated and metabolized by surviving S. frugiperda caterpillars were lower with artificial diet with ar-turmerone. Hatching of caterpillars from newly laid, 1- or 2-day-old S. frugiperda eggs was 48.6, 14.2 and 48.5%, respectively. Ar-turmerone is highly toxic to S. zeamais and S. frugiperda at low doses.

Interspecific interaction between Telenomus remus (Hymenoptera: Platygastridae) and Trichogramma pretiosum (Hymenoptera: Trichogrammatidae) on Spodoptera frugiperda (Lepidoptera: Noctuidae) eggs

This work aims to evaluate the interspecific interaction between Trichogramma pretiosum and Telenomus remus, two biological control agents of fall armyworm (Spodoptera frugiperda) eggs. Eggs of Spodoptera frugiperda previously parasitized by Telenomus remus were offered to Trichogramma pretiosum, and those parasitized by Trichogramma pretiosum were offered to Telenomus remus. The previously parasitized eggs were tested at different embryonic development stages for each parasitoid. In addition, to evaluate the competition between species, Spodoptera frugiperda eggs were offered to the parasitoids simultaneously. The behavior of the insects was recorded under a stereomicroscope. When Spodoptera frugiperda eggs were previously exposed to either parasitoid, there was no emergence of the other parasitoid. When the Telenomus remus and Trichogramma pretiosum females were placed together with Spodoptera frugiperda eggs, Telenomus remus had a greater parasitism rate. Except searching time, all Trichogramma pretiosum behaviors took a longer time than Telenomus remus behaviors. Thus, despite belonging to different families, each of these parasitoids is able to recognize host eggs previously parasitized by the other. So, this suggests that the recognition mechanism involved is not exclusively specific.