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Picture-winged flies (Diptera: Ulidiidae) are the most damaging insect pests of sweet corn (Zea mays L.) produced in Florida for the fresh market. Management of these pests, referred to as corn silk flies, relies on frequent pyrethroid applications targeting adults. In response to the need for an insecticide resistance management (IRM) program for corn silk flies in this highly intensive crop system, glass vial bioassays were conducted to determine the susceptibility of 12 corn silk fly populations to the pyrethroid beta-cyfluthrin. Two Euxesta eluta Loew and nine Euxesta stigmatias Loew populations were obtained by collecting infested ears in commercial and experimental fields in 2020 and 2021. One E. eluta laboratory colony was used as a susceptible reference population. The E. eluta reference colony was the most susceptible population, with an LC50 value of 0.01 µg/vial. The E. stigmatias field populations were generally less susceptible to beta-cyfluthrin than the E. eluta field populations, with the highest LC50 values attaining 3.51 µg/vial and 0.19 µg/vial, respectively. In addition, the five E. stigmatias populations from commercial sweet corn fields were as much as 17.6 times less susceptible than the four E. stigmatias populations from nontreated fields. Results suggest that E. stigmatias is less susceptible to pyrethroids than E. eluta. Results also suggest that corn silk flies in commercial sweet corn fields are selected for reduced pyrethroid susceptibility throughout the growing season. This study successfully used the glass vial bioassay method for corn silk flies, providing a new tool to initiate an IRM program.

Chysodeixis includens (Walker) is a polyphagous economic pest in agricultural landscapes. To detect the occurrence of this pest in the field, trapping using sex pheromone lures is often implemented. However, other plusiine species are cross-attracted to these lures and may be misidentified as C. includens due to their morphological similarities. The objectives of this study were to provide region-specific information on the abundance of C. includens throughout the year as well as document the occurrence of related plusiines crossattracted to C. includens sex pheromone traps in the Florida Panhandle. Twelve commercial fields of peanut and twelve commercial fields of cotton located across Escambia, Santa Rosa, and Jackson counties were monitored with Trécé delta traps baited with C. includens sex pheromone lures (Alpha Scents, Inc.; West Linn, OR) from June 2017 to June 2019. There was no difference in C. includens flight across dryland or irrigated fields. Identifications revealed that in addition to C. includens, the following species of the subfamily Plusiinae were crossed-attracted: Argyrogramma verruca (Fabricius) (Lepidoptera: Noctuidae), Trichoplusia ni (Hübner) (Lepidoptera: Noctuidae), Ctenoplusia oxygramma (Geyer) (Lepidoptera: Noctuidae), and Rachiplusia ou (Guenée) (Lepidoptera: Noctuidae). The occurrence of each species in the region and their flight phenology are documented. Chysodeixis includens abundance was greatest in September and decreased through December. Due to the high abundance of C. oxygramma and similar flight phenology to C. includens, this is the likeliest species to skew estimations and influence management decisions of C. includens, especially early in the crop season, when C. includens abundance is low. Made available in DSpace on 2022-05-24T05:01:37Z (GMT). No. of bitstreams: 1 Alexandre-Seasonal-flight-patterns.pdf: 30387592 bytes, checksum: 403e5b227747fa7fc1a3e4cad2be3161 (MD5) Previous issue date: 2021

Solutions for managing the growing populations of the snail Bulimulus bonariensis (Rafinesque, 1833) in row crops, notably peanut (Arachis hypogaea L.), are urgently needed in the United States. This species has become a concern to the economy and food security for infesting commercial crops in U.S. southern states. In the present study, sampling, trapping, and management strategies were investigated to support a management program for B. bonariensis in row crops. In addition, the preference of B. bonariensis for species of row crops and weeds, used as a shelter, and snail dispersal capacity were documented. The results indicated that the ideal tools for monitoring and capturing snails are beat cloth and cardboard trap, respectively. Metaldehyde 4% bait produced effective control. Tillage was tested as an alternative cultural management tactic and produced the most promising outcomes in lowering snail populations. According to snail ecological studies, peanut and soybean are the preferred crops used as shelter over cotton and corn. Among eight common winter-growing weeds, the favored non-crop host plants are cutleaf primrose (Oenothera laciniata) and dandelion (Taraxacum officinale). The snail field population tends to increase as early spring temperatures rise, with more snails becoming trapped in warm, humid conditions but not through heavy precipitation. This study provides ecology information on B. bonariensis and validates tactics to manage this invasive species in row crops, in an IPM approach.

The genus Helicoverpa includes several agricultural pests globally. Helicoverpa armigera was reported in several countries in South America in 2013, and in Puerto Rico, in 2014. This territory is considered an agricultural hub, with a high-input system of seed production in the southern region of the island, and also at the edge of the continental U.S. Possible natural dispersion of populations of H. armigera from the Caribbean or other Central American regions poses a continuing risk to the U.S. This study was performed during the post-detection scenario of H. armigera in Puerto Rico, from 2018 to 2021. A year-round pheromone trapping program of adult males indicated an increase in the population from October to March and differences in the occurrence of Helicoverpa spp. between the municipalities Juan Diaz and Salinas. The proportion of H. armigera/H. zea and detection of congeneric hybrids between these species were assessed based on genital morphology and DNA analysis. Interestingly, neither H. armigera nor expected hybrids were detected in the present study. The susceptibility of H. zea populations to the insecticides Spinetoram, Emamectin benzoate, Chlorantraniliprole, and Esfenvalerate was assessed, and an overall significant effect of insecticide susceptibility was detected. Chlorantraniliprole and Emamectin benzoate had the highest efficacy. These results contribute to the Integrated Pest Management and Insect resistance management programs to Helicoverpa spp. in Puerto Rico. In addition, provide validated information to be considered in mitigation plans, in the scenario of an invasion of H. armigera in the continental U.S.

Brassica carinata has the potential to become an economical biofuel winter crop in the Southeast U.S. An IPM program is needed to provide management recommendations for B. carinata in the region. This study serves as the first steps in the developing IPM tactics documenting pest occurrence, pest position within the canopy, and the impact of defoliation on B. carinata yield. The study was performed in Jay, FL, during the 2017–2018 and 2018–2019 winter/spring crop seasons. Pest species in B. carinata were documented by plant inspection within 16 genotypes of B. carinata, and the presence of insect pests in three canopy zones (upper, medium, and lower canopy) was documented. The defoliation impact on B. carinata was evaluated by artificial defoliation. Five levels of defoliation (2017–2018 crop season: 0%, 5%, 25%, 50%, and 100%; 2018–2019 crop season: 0%, 50%, 75%, 90%, and 100%) were artificially applied during vegetative, flowering, and pod formation stages of the commercial cultivar “Avanza64.” During the 2018–2019 crop season, two experiments were performed, a one‐time defoliation event and continuous defoliation. The plants were hand harvested and the average number of pods per plants, seeds per pod, thousand seed weight, and yield were estimated and correlated with defoliation levels. Results indicated the following species of pests associated with B. carinata: Microtheca ochroloma Stål (Coleoptera: Chrysomelidae), Plutela xylostella larvae, Pieris rapae L. (Lepidoptera: Pieridae), Diabrotica undecimpunctata Barber (Coleoptera: Chrysomelidae), Lipaphis pseudobrassicae Davis (Hemiptera: Aphididae), Leptoglossus phyllopus L. (Hemiptera: Coreidae), and Chloridea virescens F. (Lepidoptera: Noctuidae). The insect distribution within the plant canopy was not uniform. Different levels of artificial B. carinata defoliation did not affect seed weight, the number of seeds per pod, or the oil content of the seeds. The number of pods per plants and estimated yield were negatively impacted by defoliation during the vegetative and flowering stages.

Made available in DSpace on 2021-06-25T15:03:23Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-06-01 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Embrapa Helicoverpa armigera is a pest of several crops causing significant economic impact. We evaluated the insect development on different vegetative and reproductive structures of cotton, maize, and soybean compared to artificial diet. One hundred individuals were evaluated per structure (cotton leaves and bolls; maize leaves, grains, and silk; soybean leaves and pods) and artificial diet. Centesimal analyses were performed on quantifiable nutrient contents in diets. The viability of immatures (eggs, larvae, and pupae) ranged from 30% on maize leaf to 74% on cotton bolls, while on the artificial diet, it was 70%. Maize, cotton, and soybean leaves provided viability of 30, 37, and 42%, respectively, revealing these leaves tissues are less favorable to the development of H. armigera immatures compared to 'reproductive tissues'. Centesimal composition of diets compared 14 common components in all diets, which correlated significantly with larval and pupal stages and/or pupal weight. Of the 12 dietary components that significantly affected larval development time, half were negatively correlated, indicating a decrease in developmental time from their increments. In general, when insects were confined separately to substrates, the artificial diet was the most suitable for H. armigera development compared to the evaluated natural diets. However, in natural conditions, the variability of available hosts must be considered. In addition, it is acceptable for moths to select more suitable hosts for oviposition, while their larvae move to other more suitable tissues of the same plant or even migrate to other plants. Univ Estadual Paulista, Fac Ciencias Agronom, Dept Protecao Vegetal, BR-18610034 Botucatu, SP, Brazil Embrapa Cerrados, BR 020 Km 18, BR-73310970 Planaltina, Brazil Univ Brasilia, BR-73345010 Planaltina, Brazil Univ Florida, West Florida Res & Educ Ctr, 4253 Expt Rd, Jay, FL 32565 USA Univ Estadual Paulista, Fac Ciencias Agronom, Dept Protecao Vegetal, BR-18610034 Botucatu, SP, Brazil CNPq: 303892/2016-1 CNPq: 308947/2014-2 CNPq: 403376/2013-0 CNPq: 476691/2013-3 CNPq: 47304/2013-8 CNPq: 462.254.711-20 Embrapa: 02.13.14.006.00.00 Embrapa: 03.14.00.107.00.00

An important step to devise appropriate pest management strategies for armyworms (Lepidoptera: Noctuidae) in Bacillus thuringiensis Berliner (Bt) crops is to determine the lethal, sublethal, and parental effects of Bt toxins on target and nontarget pest species. Here we documented the susceptibility of black armyworm, Spodoptera cosmioides (Walker), to three Cry toxins and its life-history traits feeding on dual-toxin Bt cotton and an artificial diet containing sublethal concentrations of Cry1Ac. In concentration–response bioassays, black armyworm larvae showed low susceptibility to Cry toxins, with 853 ng/cm2 as the lowest value estimated for the median lethal concentration (LC50). The decreasing rank of toxicity was Cry1F, Cry2Aa, and Cry1Ac. Foliage of dual-toxin Bt cotton varieties (Cry1Ac + Cry1F and Cry1Ab + Cry2Ae) caused higher larval mortality than Cry1Ac-expressing cotton. Black armyworms showed reduced larval weight when growing on the Cry1Ac-treated diet, yet they reached adulthood and produced offspring. Interestingly, these larvae were grown on the control diet and showed reduced weight gain associated with the toxin exposure of the previous generation, indicating a parental effect of the exposure to Cy1Ac. The reduced larval weight was recovered in later instars, and there was no significant change in the population fitness of the parental armyworms or their offspring. To our knowledge, this is the first study documenting the parental effects of Bt toxins in insects. These results advance our understanding of potential responses of nontarget species when exposed to Bt toxins and contribute to design pest management programs for armyworms and other nontarget lepidopteran species exposed to Bt crops.

Non-random oviposition preference by target pest species on Bt and non-Bt refuge plants may increase the proportion of the population under selection pressure, reducing the value of the refuge strategy for resistance management. Here, we tested the oviposition preference for Bt over non-Bt plants and the damage-avoiding oviposition behavior of moths of the fall armyworm (FAW), Spodoptera frugiperda, a worldwide pest species with three reported cases of field-evolved resistance to Bt maize. In the greenhouse, choice assays indicated no oviposition preference for Cry1F Bt maize over its non-Bt isoline whatever intact or injured by FAW larvae. In a field experiment in a region of intensive agriculture in Brazil, the number of egg masses and FAW larvae was recorded on seven Bt maize varieties and two non-Bt maize varieties during vegetative and reproductive growth stages. There was only a weak oviposition preference by FAW moths for less damaged plants in the V10 stage. When using Cry1A.105 + Cry2Ab Bt maize and 50% refuge in a field experiment in another region in Southeastern Brazil, the number of egg masses on Bt and non-Bt plants also indicated no oviposition preference by the moths. Consistently, these results indicate that FAW moths do not distinguish Bt and non-Bt plants for oviposition and that conspecific larval damage has minor interference in the oviposition choice. Therefore, there seems to be random egg-laying preference of FAW moths in Bt maize fields, an oviposition behavior typical of generalist moth species and unlikely to be associated with the rapid selection of Bt-toxin-resistant FAWs.

Novel strategies for the management of soybean looper, Chrysodeixis includens (Walker) (Lepidoptera: Noctuidae), are needed due to its increasing importance, costs, and challenges of management in soybeans (Glycine max [L.] Merr.; Fabaceae) in the Americas. Pheromone-mediated mating disruption may be 1 such novel strategy, but an effective tool for estimating mating disruption success must be found. The technique of trapping male moths using pheromone baited traps is a common method for assessing mating disruption technology. This paper reports on the testing of 2 trap types and 3 commercially available lures containing (Z)-7-dodecenyl acetate as the major active component. Trapping was conducted at 5 locations in the southern USA in the summer of 2019. Universal moth traps and delta traps were tested in combination with the Alpha Scents, Bio Pseudoplusia, and Scentry brand lures along with unbaited traps. Overall, both trap types were effective at capturing C. includens male moths, with universal traps having a higher capture rate. The Alpha Scents and Bio Pseudoplusia lures both had a significantly higher capture rate than the Scentry lure regardless of trap design. The active components of the Scentry lure differed from the others with the inclusion of 2 known minor pheromone components (esters) of C. includens, (Z)-7-dodecenyl propionate and (Z)-7-dodecenyl butyrate. The amount of (Z)-7-dodecenyl acetate of the Scentry lure also was lower than the Alpha Scents and Bio Pseudoplusia lures. The additional esters or unidentified components (impurities) of the Scentry lures may have influenced C. includens captures. A large number of Ctenoplusia oxygramma (Geyer) (Lepidoptera: Noctuidae) were captured in traps at 3 of the locations, though not in those traps baited with the ester-containing Scentry lure. Taken together, the data provide insight into effective trapping methods for C. includens and elucidates the need for researchers to understand the effectiveness of trapping components available in a region and the need for researchers to plan for captures of non-target species in pheromone-related research.

The corn earworm, Helicoverpa zea (Boddie) (Lepidoptera: Noctuidae), is a major target pest of pyramided Bt maize and cotton in the U.S. In 2017 and 2018, notable ear damage and larval survival of H. zea were observed on pyramided Cry1A.105/Cry2Ab2 maize in some fields in northeast Louisiana, U.S. The objective of this study was to determine if the field control problem was due to resistance development to the Bt proteins in plants. A total of 15 H. zea populations were collected from Bt and non-Bt maize plants in 2017 and 2018 in multiple locations in Louisiana, Florida, and Georgia. Diet-overlay bioassays showed that LC50s of Cry1A.105 and Cry2Ab2 for populations collected from the areas with control problems in northeast Louisiana were as much as >1623- and 88-fold greater than that of a susceptible strain, respectively. In addition, two field trials in 2018 validated that Cry1A.105/Cry2Ab2 maize failed in managing natural H. zea populations, while Bt maize containing Vip3A was effective in northeast Louisiana. Results of the study documented that the observed field control problems of Cry1A.105/Cry2Ab2 maize against H. zea in northeast Louisiana were due to resistance development of the insect to the Bt proteins in plants. This is the first documentation of field-evolved resistance to pyramided Bt maize in a target insect species in southern U.S. However, susceptibility levels to Cry1A.105 and Cry2Ab2 varied greatly among populations collected from the three states, suggesting uneven distributions of the resistance in the region.

The corn earworm, Helicoverpa zea (Boddie), is a major pest targeted by pyramided Bacillus thuringiensis (Bt) corn and cotton in the U.S. Cry1Ab is one of the first insecticidal toxins used in Bt crops, while Vip3A is a relatively new toxin that has recently been incorporated into Cry corn with event MIR 162 and Cry cotton varieties to generate pyramided Bt traits targeting lepidopteran pests including H. zea. The objectives of this study were to determine the current status and distribution of the Cry1Ab resistance, and evaluate the susceptibility to Vip3Aa20 expressed in MIR 162 corn in H. zea in the southeastern U.S. During 2018 and 2019, 32 H. zea populations were collected from non-Bt corn (19 populations), Cry corn (12), and Cry/Vip3A cotton (1) across major corn areas in seven southeastern states of the U.S. Susceptibility of these populations to Cry1Ab and Vip3Aa20 was determined using diet-overlay bioassays. Compared to a known susceptible insect strain, 80% of the field populations were 13- to &gt, 150-fold resistant to Cry1Ab, while their response to Vip3Aa20 ranged from &gt, 11-fold more susceptible to 9-fold more tolerant. Mean susceptibility to each Bt toxin was not significantly different between the two groups of the populations collected from non-Bt and Bt crops, as well as between the two groups of the populations collected during 2018 and 2019. The results show that resistance to Cry1Ab in H. zea is widely distributed across the region. However, the Cry1Ab-resistant populations are not cross-resistant to Vip3Aa20, and H. zea in the region is still susceptible to the Vip3Aa20 toxin. Vip3Aa20 concentrations between 5 and 10 &micro, g/cm2 may be used as diagnostic concentrations for susceptibility monitoring in future. Additional studies are necessary to elucidate the impact of the selection with Bt corn on resistance evolution in H. zea to Vip3A cotton in the U.S.

Soybean is an established crop with a high production value in the United States. The insects that utilize soybean as a food source have changed drastically over the last 20 yr. Much of the extension literature summarizing pest species distribution and abundance is out of date. This article provides profiles for five common soybean caterpillars, including description, life cycle, and injury to plants.

The distribution of lepidopteran pests in soybean (Glycine max (L.) Merr.) is a current knowledge gap limiting accurate prioritization of Integrated Pest Management (IPM) research. Regional characterizations of lepidopteran distribution in soybean are now more than 25 yr old. The goal of this study was to generate a contemporary assessment of the distribution and population persistence of lepidopteran soybean pests. To understand which species are currently infesting soybean and their persistence, we conducted a survey of soybean entomologists with responsibility for approximately 33.6 million hectares of production in 31 U.S. states. Soybean entomologists were asked questions about presence of lepidopteran pests and their persistence in their state. We focused this survey on five lepidopteran pests: corn earworm (Helicoverpa zea Boddie) (Lepidoptera: Noctuidae), green cloverworm (Hypena scabra Fabricius) (Lepidoptera: Erebidae), painted lady (Vanessa cardui L.) (Lepidoptera: Nymphalidae), soybean looper (Chrysodeixis includens Walker) (Lepidoptera: Noctuidae), and velvetbean caterpillar (Anticarsia gemmatalis Hübner) (Lepidoptera: Erebidae). Soybean entomologists also provided insight into regionally relevant or sporadic lepidopteran soybean pests. Participants were also questioned about common scouting practices in each state. Results of this survey highlight dissimilar geographic distribution and relative persistence of lepidopteran pests in soybean. Clear differences in occurrence and abundance among species provide important contemporary distributions and persistence estimates. Assessments of scouting practices demonstrate a need to improve IPM adoption in some states. Results of this study and its complementary pest profile (concurrently published in JIPM) provide a contemporary foundation for studies of lepidopteran soybean pests.

Feltia subterranea (Fabricius), commonly known as the granulate cutworm, is a common species of owlet moths (Noctuidae) of major agricultural importance, widely distributed in Nearctic and Neotropical regions. This study was conducted to determine the species biological parameters, gather information about its larval host plants, and assess the agricultural significance of this species in the Americas. The viability of the egg, larval, pupal stages, and prepupal period was 98, 98, and 100%, respectively, under laboratory conditions. The average duration of the egg, larval, pupal stages, and prepupal period was 3, 17, 4, and 13 d, respectively. All laboratory-reared larvae developed through five instars. The growth ratio was 1.93 for females and 1.85 for males. The duration of the larval stage was significantly longer in females than in males from the fourth instar. The duration of the pupal stage was significantly shorter in females than in males. When larval and pupal stage durations were combined, there were no significant differences in total development time as a function of sex. In total, 159 botanical taxa belonging to 41 families were recorded as host species for F. subterranea. The families with the greatest number of host species were Fabaceae (22), Poaceae (19), Asteraceae (16), Brassicaceae (13), Solanaceae (12), Amaranthaceae (7), Cucurbitaceae (7), and Malvaceae (5). It is noteworthy that the large number of native weeds used by F. subterranea as host plants could represent a significant source of infestation of crops in the agricultural landscape. Fil: Specht, Alexandre. Embrapa Cerrados; Brasil Fil: Dias, Fernando M. S.. Universidade Estadual de Londrina; Brasil. Universidade Federal do Paraná; Brasil Fil: San Blas, Diego German. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Ciencias de la Tierra y Ambientales de La Pampa. Universidad Nacional de La Pampa. Facultad de Ciencias Exactas y Naturales. Instituto de Ciencias de la Tierra y Ambientales de La Pampa; Argentina Fil: Roque-Specht, Vânia F.. Universidade do Brasília; Brasil Fil: Casagrande, Mirna M.. Universidade Federal do Paraná; Brasil Fil: Mielke, Olaf H. H.. Universidade Federal do Paraná; Brasil Fil: Montezano, Débora G.. Corteva Agrisciense; Estados Unidos Fil: Barbosa Santos, Izailda. University of Florida; Estados Unidos Fil: Paula-Moraes, Silvana V.. University of Florida; Estados Unidos Fil: Hunt, Thomas E.. Universidad de Nebraska - Lincoln; Estados Unidos Fil: Malaquias, Juaci V.. Embrapa Cerrados; Brasil Fil: Bonfin, Felipe A. D.. Embrapa Cerrados; Brasil. Instituto Federal de Brasília; Brasil Fil: Vieira, Paulo V. M.. Embrapa Cerrados; Brasil. Universidade do Brasília; Brasil

The first detection of Helicoverpa armigera (Hubner) (Lepidoptera: Noctuidae) in Brazil pointed to a gloomy future for South American agriculture in the 2012/2013 harvest, and insecticide sales increased exponentially during 2013 and 2014. However, after this outbreak, the population of this insect returned to manageable levels. This study documents data on H. armigera moth collection using light traps during the outbreak in two locations: (a) western region of the state of Bahia, including population levels of H. armigera and main noctuid pests during the big outbreak (February and March 2013); (b) Federal District, including monthly data for five growing seasons (July 2012–June 2017). During the outbreak, an average of 527.3 moths were collected per trap (cotton crop, March) in the western region of Bahia each night, while the maximum average in the Federal District was 75.4 moths (January). The number of moths decreased in the following growing seasons, and in October 2016, the maximum number was 2.8 moths per trap. Aspects related to the variations of H. armigera and Helicoverpa zea (Boddie) populations, including the study of phenology and relationship with climatic factors and Oceanic Nino Index, were analyzed and discussed. All aspects are approached to contribute to the management of lepidopteran pests, especially H. armigera, in the productive systems of the Brazilian Cerrado.

Previous studies have reported that the corn earworm/bollworm, Helicoverpa zea (Boddie), has developed field resistance to pyramided Bacillus thuringiensis (Bt) Cry1A/Cry2A maize and cotton in certain areas of the southeastern United States. The objective of the current study was to determine the current status and distribution of the resistance to Cry1A.105 and Cry2Ab2 in H. zea. In the study, 31 H. zea populations were collected from major maize planting areas across seven southeastern states of the United States during 2018 and 2019 and assayed against the two Bt proteins. Diet over-lay bioassays showed that most of the populations collected during the two years were significantly resistant to the Cry1A.105 protein. Most of the populations collected during 2019 were also resistant to Cry2Ab2, while significant variances were observed in the susceptibility of the populations collected during 2018 to Cry2Ab2. The results showed that Cry1A.105 and Cry2Ab2 resistance in H. zea is widely distributed in the regions sampled. The resistance to Cry1A.105 appeared to have plateaued, while selection for Cry2Ab2 resistance is likely still occurring. Thus, effective measures for mitigating the Cry1A/Cry2A resistance need to be developed and implemented to ensure the sustainable use of Bt crop biotechnology.

Helicoverpa armigera is a pest of several crops causing significant economic impact. We evaluated the insect development on different vegetative and reproductive structures of cotton, maize, and soybean compared to artificial diet. One hundred individuals were evaluated per structure (cotton leaves and bolls; maize leaves, grains, and silk; soybean leaves and pods) and artificial diet. Centesimal analyses were performed on quantifiable nutrient contents in diets. The viability of immatures (eggs, larvae, and pupae) ranged from 30% on maize leaf to 74% on cotton bolls, while on the artificial diet, it was 70%. Maize, cotton, and soybean leaves provided viability of 30, 37, and 42%, respectively, revealing these leaves tissues are less favorable to the development of H. armigera immatures compared to 'reproductive tissues'. Centesimal composition of diets compared 14 common components in all diets, which correlated significantly with larval and pupal stages and/or pupal weight. Of the 12 dietary components that significantly affected larval development time, half were negatively correlated, indicating a decrease in developmental time from their increments. In general, when insects were confined separately to substrates, the artificial diet was the most suitable for H. armigera development compared to the evaluated natural diets. However, in natural conditions, the variability of available hosts must be considered. In addition, it is acceptable for moths to select more suitable hosts for oviposition, while their larvae move to other more suitable tissues of the same plant or even migrate to other plants.

Insecticidal toxins from Bacillus thuringiensis (Bt) are valuable tools for pest management worldwide, contributing to the management of human disease insect vectors and phytophagous insect pests of agriculture and forestry. Here, we report the effects of dual and triple Bt toxins expressed in transgenic cotton cultivars on the fitness and demographic performance of Helicoverpa zea (Boddie), a noctuid pest known as cotton bollworm and corn earworm. Life-history traits were determined for individuals of three field populations from a region where H. zea overwintering is likely. Triple-gene Bt cotton cultivars expressing Cry and Vip3Aa toxins killed 100% of the larvae in all populations tested. In contrast, dual-gene Bt cotton expressing Cry1Ac+Cry1F and Cry1Ac+Cry2Ab2 allowed population growth with the intrinsic rate of population growth (rm) 38% lower than on non-Bt cotton. The insects feeding on Bt cotton plants expressing Cry1Ac+Cry2Ab2, Cry1Ac+Cry1F, or Cry1Ab+Cry2Ae exhibited reduced larval weight, survival rate, and increased development time. Additionally, fitness parameters varied significantly among the insect populations, even on non-Bt cotton plants, likely because of their different genetic background and/or previous Bt toxin exposure. This is the first report of the comparative fitness of H. zea field populations on dual-gene Bt cotton after the recent reports of field resistance to certain Bt toxins. These results document the population growth rates of H. zea from an agricultural landscape with 100% Bt cotton cultivars. Our results will help to refine models designed to predict resistance evolution and improve insect resistance management for Bt crops.

Insecticidal toxins from Bacillus thuringiensis (Bt) are valuable tools for pest management worldwide, contributing to the management of human disease insect vectors and phytophagous insect pests of agriculture and forestry. Here, we report the effects of dual and triple Bt toxins expressed in transgenic cotton cultivars on the fitness and demographic performance of Helicoverpa zea (Boddie)—a noctuid pest, known as cotton bollworm and corn earworm. Life-history traits were determined for individuals of three field populations from a region where H. zea overwintering is likely. Triple-gene Bt cotton cultivars that express Cry and Vip3Aa toxins killed 100% of the larvae in all populations tested. In contrast, dual-gene Bt cotton that express Cry1Ac+Cry1F and Cry1Ac+Cry2Ab allowed population growth with the intrinsic rate of population growth (rm) 38% lower than on non-Bt cotton. The insects feeding on Bt cotton plants that express Cry1Ac+Cry2Ab, Cry1Ac+Cry1F, or Cry1Ab+Cry2Ae exhibited reduced larval weight, survival rate, and increased development time. Additionally, fitness parameters varied significantly among the insect populations, even on non-Bt cotton plants, likely because of their different genetic background and/or previous Bt toxin exposure. This is the first report of the comparative fitness of H. zea field populations on dual-gene Bt cotton after the recent reports of field resistance to certain Bt toxins. These results document the population growth rates of H. zea from an agricultural landscape with 100% Bt cotton cultivars. Our results will contribute to the development and validation of resistance management recommendations.

The fall armyworm, Spodoptera frugiperda (J.E. Smith, 1797) (Lepidoptera: Noctuidae), is the most important noctuid pest in the Americas and has recently become an invasive pest in Africa. A detailed record of S. frugiperda's host plants is essential to better understand the biology and ecology of this pest, conduct future studies, and develop Integrated Pest Management programmes. In this study, we collected and systematically arranged the fragmented bibliographic information on S. frugiperda feeding records. Furthermore, we registered new records of host plants for S. frugiperda based on eight years of surveys in Brazil. The literature review and surveys resulted in a total of 353 S. frugiperda larval host plant records belonging to 76 plant families, principally Poaceae (106), Asteraceae (31) and Fabaceae (31). The literature search revealed 274 (77 % of total) bibliographic records, while 82 (23 %) are new records from surveys in Brazil. The new comprehensive and updated host plant list will improve our understanding of pest biology and management, as well as facilitate future studies on this pest.

Developmental changes in target-pest susceptibility to Bacillus thuringiensis (Bt) toxins matter to resistance management in Bt crops, especially in certain refuge modalities. We determined the cumulative, lethal and sublethal effects of Bt corn hybrids during the larval stages of Bt-resistant populations of fall armyworm, Spodoptera frugiperda (Lepidoptera: Noctuidae). The susceptibility to Bt corn traits depended on the fall armyworm population and the developmental stage of the larvae. On Cry1A.105 + Cry2Ab corn, neonate-to-adult survival rates of Cry1F-resistant larvae was 4% when the exposure started in the neonate and 87% when in late instars. Cry1F-resistant larvae feeding on Cry1A.105 + Cry2Ab corn throughout larval development produced viable adults that successfully reproduced without any noticeable disadvantage. In contrast, Bt susceptible larvae had high mortality on Cry1A.105 + Cry2Ab corn, and no adults emerged from the larvae exposed to the toxins, independently of the larval stage. Cry1Ab + Vip3Aa corn killed all larvae in any instar, regardless of the Bt-toxin resistance of the fall armyworm population. These results consistently indicate that Cry1F resistance reduces the susceptibility to Cry1A.105 + Cry2Ab toxins and that Vip3Aa has a high potential to control field populations of Cry-toxin-resistant fall armyworm, even if there was plant-to-plant larval movement to Vip Bt plants in late instars in a scenario seed-mixture refuge. We discuss the implications of our findings for sustainable resistance management.

Chrysodeixis includens (Walker, [1858]) is currently the main plusiine pest in the Americas, not only because of the damage caused to soybean, but also with several crop species in a broad geographical range. However, its population dynamics is still poorly understood, despite outbreak records that are common across different locations in the Americas. The current study aimed at identifying phenological patterns of C. includens emphasizing its differences among the three years of sampling effort in an intercropping area of the Brazilian Savanna. Thereafter, we tested whether the El Niño size effect, meteorological factors, or soybean, corn and wheat cycles, are better predictors of its monthly abundance. The insects were collected with a light trap during five consecutive nights (repetitions) during 35 new moons. In total, 2026 specimens were collected in all months of the year although not consecutively. Across each year, monthly abundance of C. includens was non-uniform, characterized by sharp population peaks concentrated in the rainy season. These peaks varied from January until March, depending on the year sampled. We found that the local soybean cycle and El Niño effect to significantly influence the species abundance across the entire period of study. These results aid in understanding the species population dynamics and its status as a pest, providing evidence of factors that determine its phenological patterns. Although it presents a very defined phenology, the population dynamics of C. includens varies significantly between years and locations, which demonstrates the importance and need to monitor local populations of larvae and adults for its management. Keywords: Circular statistics, Phenology, Pest-species, Population outbreaks, Soybean phenology

BACKGROUND Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) is one of the major pests of maize and is in the same feeding guild as the noctuid pests Helicoverpa zea (Boddie) and Helicoverpa armigera (Hubner), recently reported in South and North America. The intraguild interactions of these species were assessed in laboratory and field conditions by determining the survival of larvae in interaction scenarios with non-Bt maize silks and ears. Moreover, a video tracking system was utilized to evaluate behavioral parameters during larval interactions in scenarios with or without food. RESULTS In intraguild interactions, S. frugiperda had greater survival (55–100%) when competing with Helicoverpa spp. in scenarios where larvae were the same instar or when they were larger (fourth versus second) than their competitor. Frequency and time in food of S. frugiperda larvae were negatively influenced by interactions. Larvae of S. frugiperda moved shorter distances (less than 183.03 cm) compared with H. zea. CONCLUSION Overall, S. frugiperda had a competitive advantage over Helicoverpa spp. This study provides significant information regarding noctuid behavior and larval survival during intraguild interactions, which may impact pest prevalence and population dynamics, thereby affecting integrated pest management and insect resistance management of these species in maize. © 2017 Society of Chemical Industry

This study aimed to evaluate the biotic potential and life table of individuals of Helicoverpa armigera (Hubner) from different host plants (citrus, corn, and cotton) and Brazilian states (Sao Paulo, Distrito Federal, and Bahia) in artificial diet, under laboratory conditions (25 ± 1°C, 70 ± 10% RH, 14 h photophase). The longevity, pre-, post- and oviposition periods, fecundity, and fertility of 15 mating pairs per origin were evaluated. We also compared the reproductive parameters of each group of insects (Sao Paulo (SP), Distrito Federal (DF), and Bahia (BA)), including the net reproductive rate (Ro), mean generation time (T), intrinsic rate of increase (r m), and finite rate of increase (λ). Microsatellite analysis from individuals collected in different locations and host plants did not show differences among the parental insects. It was verified that parental progeny collected in cotton fields from Bahia had a higher biotic potential, a higher reproductive rate (Ro), and a better fecundity compared to the insects from remaining regions. The life table charts indicate that the highest values for the reproductive parameters of the Bahia progeny are associated with higher specific fertility, particularly in early adulthood. The greatest biotic potential of the Bahia progeny may be due to increased selection pressure from the insecticide used (organophosphate and pyrethroid) on cotton crops compared to that of other crops, as well due to the massive adoption of Bt cotton-producing areas of that state from 2013 outbreaks.

Hybridization between invasive and native species has raised global concern given the dramatic increase in species range shifts and pest outbreaks due to climate change, development of suitable agroecosystems, and anthropogenic dispersal. Nevertheless, secondary contact between sister lineages of local and invasive species provides a natural laboratory to understand the factors that determine introgression and the maintenance or loss of species barriers. Here, we characterize the early evolutionary outcomes following secondary contact between invasiveHelicoverpa armigeraandH. zeain Brazil. We carried out whole-genome resequencing ofHelicoverpamoths from Brazil in two temporal samples: during the outbreak ofH. armigerain 2013, and more recent populations from 2017. There is evidence for a burst of hybridization and widespread introgression from localH. zeainto invasiveH. armigeracoinciding withH. armigeraexpansion in 2013. However, inH. armigera, admixture proportions were reduced between 2013 and 2017, indicating a decline in hybridization rates. Recent populations also showed shorter introgressed tracks suggesting selection against admixture. In contrast to the genome-wide pattern, there was striking evidence for introgression of a single region including an insecticide-resistance allele from the invasiveH. armigerainto localH. zea,which increased in frequency over time but was localized within the genome. In summary, despite extensive gene-flow after secondary contact, the species boundaries are largely maintained except for the single introgressed region containing the insecticide-resistant locus. We document the worst-case scenario for an invasive species, in which there are now two pest species instead of one, and the native species has acquired resistance to pyrethroid insecticides through introgression and hybridization, with significant implications for pest management in future population expansions and introductions of novel resistance genes from new invasiveH. armigerapopulations.Author summarySecondary contact occurs when related species with non-overlapping ranges are geographically reunited. Scenarios of secondary contact have increased due to anthropogenic movement of species outside of their native range, often resulting in invasive species that successfully spread and stabilised in the new environment. This is the case forHelicoverpa armigera, a major agricultural pest in the Old World that has recently invaded the Americas, where it reunited with its closest relative,H. zea. While some authors reported hybridisation, and hypothesised about the potential emergence of novel ecotypes and the exchange of pesticide-resistant genes, these outcomes have not been tested yet. We examine these outcomes by sequencing individuals from both species in Brazil, collected in 2013 after outbreaks ofH. armigerawere reported, and individuals collected during 2017. We discovered that despite hybridisation, these moths have not collapsed into a single species nor formed new ecotypes, and that the species distinctiveness is maintained through selection against most of the foreign genotypes that cross species boundaries. However, we found that hybridisation mediated the rapid acquisition of aH. armigeragene conferring resistance to pyrethroids byH. zea. The overall decline in populations of both species during the interval covered by this study means that our results are likely to reflect the consequences of hybridization events early after invasion, despite the likely ongoing introduction ofH. armigeragenetic diversity through trade across the South American continent. Our results provide a rare example of adaptive transferral of variation right after invasion and elucidate the dynamics of insecticide resistance evolution inH. zea.

BACKGROUND Pesticide resistance is a growing issue worldwide, and susceptibility of pest populations should be monitored in migratory intersection regions for successful resistance management. We determined the susceptibility of eight noctuid species from the Florida Panhandle to bifenthrin (pyrethroid) and chlorantraniliprole (diamide). Larvae from field and laboratory populations were exposed to commercial insecticide formulations using the leaf-dip method in concentration-mortality bioassays. RESULTS The field populations of Helicoverpa zea (Boddie), Spodoptera frugiperda (Smith), S. eridania (Stoll), S. exigua (Hubner) and Chloridea virescens (Fabricius) had reduced susceptibility to bifenthrin compared with the laboratory populations. Resistance ratios to bifenthrin were as high as 10 071-fold in S. exigua and 436-fold in S. frugiperda, while there was no reduced susceptibility in Agrotis ipsilon (Hufnagel). The susceptibility to chlorantraniliprole was similar between the field and laboratory populations studied, except for S. exigua that exhibited 630-fold resistance to the diamide. The probit regression equations indicated that the larval mortality of S. exigua and S. frugiperda populations was

Knowledge of dispersal and spatial dynamics of pest populations is fundamental for implementation of integrated pest management and integrated resistance management. This study evaluated 1) the effectiveness of egg white albumin protein to mark larvae and adults of two polyphagous and highly mobile pests, Spodoptera frugiperda (J.E. Smith) (fall armyworm) and Helicoverpa zea (Boddie) (corn earworm) (Lepidoptera: Noctuidae), and 2) the sensitivity of polyvinylidene difluoride membrane (dot blot) in detecting albumin on marked insects. Laboratory and field experiments tested egg albumin as a protein marker, which was detected using two enzyme-linked immunosorbent assay (ELISA), microplate, and dot blot. In the laboratory, 100% of the moths sprayed with 20% egg white solution acquired the albumin marker, which was detected through the last time point tested (5 d) after application. Egg albumin was not effective at long-term marking of larvae, detected only prior the molting to the next instar. Albumin application in field cages resulted in a high percentage of moths detected as marked at 24 h and 5 d for both species. Egg albumin applied in the open field resulted in 15% of the recaptured corn earworm moths marked with most of them collected 150 m from the application area, although some were captured as far as 1,600 m within approximately 6 d after adult emergence. The results indicated egg albumin is a suitable marker to study the dispersion of fall armyworm and corn earworm in the agroecosystem and dot blot was as effective to detect egg albumin as was indirect ELISA.

The use of GMO expressing Bt toxin in soybean production has increased significantly in the last years in Brazil in order to manage the damage caused by lepidopteran pests. In this study, we compared the richness and abundance of owlet moths (Noctuoidea) associated with Bt and non-Bt soybean. We determined the temporal variations as a function of phenology, and correlated the population variations of the most common species with meteorological variables. The research was conducted at the experimental area of Embrapa Cerrados. The collection method used was differentiated being suppressive and absolute. A total of 13 species were collected, of which eight occurred on Bt soybeans. The most representative taxa were Chrysodeixis includens (72.87%), Anticarsia gemmatalis (18.17%) and Spodoptera spp (5.22%). The number of larvae belonging to species targeted by the Bt technology was 10 times lower on Bt than on non-Bt soybeans. Utetheisa ornatrix and Elaphria deltoides were recorded on soybean for the first time, observing larvae of both species in non-Bt soybean and those of U. ornatrix also in Bt soybean. Only A. gemmatalis larvae correlated (p

Made available in DSpace on 2018-11-26T15:43:40Z (GMT). No. of bitstreams: 0 Previous issue date: 2017-03-01 Coordination for the Improvement of Higher Education Personnel The fall armyworm, Spodoptera frugiperda (J. E. Smith) and the corn earworm, Helicoverpa zea (Boddie) are among the main pests of maize. Both species exhibit cannibalistic behavior and quite often share the same feeding guild in maize (maize ears), which can result in several interspecific and intraspecific interactions. Paired interaction scenarios of intraspecific and interspecific larvae were assessed in arenas in the presence and absence of food to characterize movements resulting from interactions of these insects. There was a difference in the frequency of behavioral movements in all the interactions, except for S. frugiperda in the presence of food. Head touching and recoiling were the predominant movements in most of the interaction scenarios. Spodoptera frugiperda exhibited a predominance of defensive movements when competing against H. zea in the same instars. Cannibalism and predation occurred frequently in interactions involving 6th instar of H. zea against opponents in 4th instar. Larvae of H. zea show a higher aggressive movement than S. frugiperda. The larvae of S. frugiperda take advantage during the interactions, although they present more defensive movements compared to H. zea. This study provides relevant information regarding the interaction of these species and intraguild interaction, which might influence the population dynamics and the competitive displacement of pest species that share the same ecological niche. Sao Paulo State Univ, Dept Crop Protect, Coll Agron Sci, BR-18610307 Botucatu, SP, Brazil Univ Nebraska Lincoln, Dept Entomol, ENREC Haskell Agr Lab, Concord, NE 68728 USA Univ Nebraska Lincoln, Dept Entomol, Lincoln, NE 68583 USA Embrapa Cerrados, BR 020 Km 18, BR-73310970 Planaltina, DF, Brazil Sao Paulo State Univ, Dept Crop Protect, Coll Agron Sci, BR-18610307 Botucatu, SP, Brazil Coordination for the Improvement of Higher Education Personnel: 99999.002564/2014-09

Made available in DSpace on 2018-11-26T15:29:59Z (GMT). No. of bitstreams: 0 Previous issue date: 2016-06-01 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Integrated pest management (IPM) and insect resistance management (IRM) in various cropping systems demand a comprehensive understanding of insect behavior. Among the needed information is basic charaterizations of larval movement and dispersion of some insect-pests, such as the noctuids Striacosta albicosta (Smith) and Spodoptera frugiperda (J.E. Smith). We investigated the plant-to-plant movement of western bean cutworm and fall armyworm larvae in field of maize. Experiments on S. albicosta were conducted between 2008 and 2010. A main study with this pest was performed in 2012 in a randomized complete block design (RCBD) with nine replications. An S. frugiperda study was performed in 2013 in an RCBD with eight replications. The plant-to-plant movement and larval survival were measured in plots with maize nontoxic to the insects. The larval survival of S. albicosta presented high variety throughout the years. Although S. frugiperda survival was relatively low during 2013, it did not compromise the larval assessment. Larvae of both species dispersed governed by nondirectional sensory information, and presented aggregated and symmetrical distribution; however, fall armyworm remained nearer the release point. These results may help the IPM components, such as scouting and economic threshold, as well as the implementation of refuge and seed mixture strategies for IRM. Sao Paulo State Univ, Dept Crop Protect, Coll Agron Sci, BR-18610307 Botucatu, SP, Brazil EMBRAPA Cerrados, BR-73310970 Planaltina, DF, Brazil Univ Nebraska, NEREC Haskell Agr Lab, Dept Entomol, 57905 866 Rd, Concord, NE 68728 USA Sao Paulo State Univ, Dept Crop Protect, Coll Agron Sci, BR-18610307 Botucatu, SP, Brazil

Bacillus thuringiensis (Bt) varieties of soybean and cotton have been widely adopted in South America, but defoliation by the southern armyworm Spodoptera eridania (Lepidoptera: Noctuidae) has increased in these crops. This issue may be linked to the low inherent susceptibility of the larvae to some Bt toxins. However, this hypothesis was not yet tested, nor was the potential sublethal effects of the toxins on larval development of southern armyworm. Here we determined the response of southern armyworm larvae exposed to Bt toxins representative of those used in soybean and cotton cultivars. In concentration-response bioassays, whereas a low median lethal concentration (LC50) value was found for Cry2Aa (11 ng/cm2), higher LC50 values were found for Cry1F (>3000 ng/cm2) and Cry1Ac (>10000 ng/cm2). Larval growth of the southern armyworm showed a hormesis-like response when the larvae were reared on artificial diet containing increasing Cry1Ac concentrations. Such enhanced larval growth was also observed when fresh foliage of Cry1Ac soybean or its lyophilized tissue in an artificial diet were fed to the larvae. Although the foliage of the dual-toxin Bt cotton producing Cry1Ac + Cry2Ab killed all larvae, its lyophilized leaf tissue caused no significant larval mortality when diluted 25 times. These results indicate that southern armyworm larvae have low inherent susceptibility to Cry1Ac and Cry1F toxins, while the Cry1Ac Bt toxin can enhance its larval growth. In addition, Cry1Ac + Cry2Ab Bt cotton may not meet the high-dose condition for the southern armyworm. These findings have important implications for pest management of the southern armyworm, which is discussed.

Brassica carinata is an annual oilseed crop used for the commercial production of jet fuel. One of the challenges to commercialization of this crop in the southeastern United States has been frost damage. This 4-page fact sheet discusses symptomology and ways to minimize risk of frost damage to carinata. Written by Michael J. Mulvaney, Ramdeo Seepaul, Ian Small, David Wright, Silvana Paula-Moraes, Carl Crozier, Paul Cockson, Brian Whipker, and Ramon Leon, and published by the UF/IFAS Agronomy Department, May 2018. https://edis.ifas.ufl.edu/ag420

EnglishGiven the increasing importance of Elaphria agrotina (Guenee) (Lepidoptera: Noctuidae) in corn crops, especially in the Brazilian Savannah biome, the present research aimed to study its development and survival on Greene’s and Poitout & Bues’s artificial diets (25±1°C, 70±10% relative humidity [RH] and 12h photophase). Poitout & Bues’s diet was more suitable than Greene’s diet, providing higher survival percent (77.51% vs. 5.57%), lower development time (49.81 days vs. 55.24 days) and higher fecundity (167.65 vs. 84.9 eggs), respectively. All the caterpillars reared on Poitout & Bues’s diet passed through six instars, while almost half of the larvae reared on Greene’s diet went through one less instar stage. Regarding the main reproductive parameters, higher average time of generation (T) and lower values of net rates of reproduction (Ro), and increased (rm) intrinsic and finite reason of increase (λ), were observed for larvae reared on Greene’s diet. Results presented in this study indicated that Poitout & Bues’s diet is more suitable for maintenance of colonies of E. agrotina as compared to Greene’s diet. Key words: row crops; adequacy; biology; lepidopteran-pests; maintenance of colonies portuguesCom a crescente importância de Elaphria agrotina (Guenee) (Lepidoptera: Noctuidae) em cultivos de milho, especialmente no Bioma Cerrado, o presente trabalho objetivou comparar o seu desenvolvimento e sobrevivencia em dieta artificial de Greene e Poitout & Bues (25±1oC, 70±10% umidade relativa [UR] e fotofase de 12h). A dieta de Poitout & Bues foi mais adequada que a dieta de Grenne, proporcionando maior sobrevivencia (77.51% e 5.57%), menor tempo de desenvolvimento (49.81 dias e 55.24 dias) e maior fecundidade (167.65 ovos e 84.9 ovos), respectivamente. Todas as lagartas alimentadas com dieta de Poitout & Bues passaram por seis instares, enquanto que praticamente metade das provenientes da dieta de Greene passou por um instar a menos. Lagartas alimentadas com dieta de Greene, apresentaram maior valor do tempo medio de cada geracao (T) e menores valores das taxas liquida de reproducao (Ro), intrinseca de aumento (rm) e razao finita diaria de aumento (λ). Os resultados deste estudo indicam a recomendacao da dieta de Poitout & Bues para manutencao de colonias e criacao massal de E. agrotina quando comparada com a dieta de Greene. Palavras-chave: culturas anuais; adequacao; biologia; lepidopteros-praga; manutencao de colonias de insetos.

The present research updates the systematic position and nomenclature of Lepidoptera associated with soybean crops in Argentina, Brazil, Chile and Uruguay. Scientific literature lists 69 species of Lepidoptera feeding on soybean plants. These species are representatives of the Superfamilies Noctuoidea (31), Pyraloidea (13), Hesperioidea (12), Tortricoidea (5), Geometroidea (5), and Bombycoidea (3). Diversity of Lepidoptera associated to crop, injury in different parts of the plant, and changes in species composition are discussed considering the changes in plant disease management, introduction of plants expressing Bt proteins, and the recent introduction of Helicoverpa armigera (Hübner) as a new crop pest. RESUMO: O presente estudo atualiza a posição sistemática e a nomenclatura dos lepidópteros associados com a cultura da soja na Argentina, Brasil, Chile e Uruguai. A literatura científica relaciona 69 espécies de Lepidoptera cujas larvas se alimentam de soja. As espécies incluem representantes das Superfamílias Noctuoidea (31), Pyraloidea (13), Hesperioidea (12), Tortricoidea (5), Geometroidea (5), and Bombycoidea (3). A diversidade dos lepidópteros associados com a cultura, as injúrias em diferentes partes da planta e alterações na composição das espécies são discutidas considerando mudanças no manejo de doenças da cultura, a introdução de plantas expressando proteínas Bt e a recente introdução de Helicoverpa armigera (Hübner) como uma nova praga da soja.