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Frankliniella flower thrips are pests of numerous fruit and vegetable crops as they feed and reproduce in the flowers and fruits. The invasive Frankliniella occidentalis (Pergande) from the Southwestern United States, an economic pest in Florida since 2005, and the native Frankliniella bispinosa Morgan are both found in Florida strawberries. The objective of this research was to characterize injury to strawberry fruit from these species. Densities of 0, 2, 4, 8, 16, or 32 adult females of each species were caged on a strawberry plant with one flower. The cages were removed after 2, 5, or 10 d, and the number of surviving adults and the number of larvae determined. Injury was quantified on the mature fruit 21 d after thrips were introduced onto the experimental plant. Initial densities as low as two adult F. occidentalis females per flower decreased fruit set and increased cat-facing on the fruits that developed. There were no significant effects on fruit set and cat-facing by any initial density of F. bispinosa. Feeding by thrips on the small, green fruit affected the size and shape of the mature fruit: the diameters were decreased as a linear function of increased feeding by F. bispinosa, and the weights were decreased as a linear function of increased feeding by F. occidentalis. Overall, results showed that F. occidentalis was more damaging to strawberry than F. bispinosa. The differences in pest status between these common flower thrips species in Florida presents challenges to management programs.

Western flower thrips, Frankliniella occidentalis, first arose as an important invasive pest of many crops during the 1970s–1980s. The tremendous growth in international agricultural trade that developed then fostered the invasiveness of western flower thrips. We examine current knowledge regarding the biology of western flower thrips, with an emphasis on characteristics that contribute to its invasiveness and pest status. Efforts to control this pest and the tospoviruses that it vectors with intensive insecticide applications have been unsuccessful and have created significant problems because of the development of resistance to numerous insecticides and associated outbreaks of secondary pests. We synthesize information on effective integrated management approaches for western flower thrips that have developed through research on its biology, behavior, and ecology. We further highlight emerging topics regarding the species status of western flower thrips, as well as its genetics, biology, and ecology that facilitate its use as a model study organism and will guide development of appropriate management practices.

The economic impact of the greenhouse thrips, Heliothrips haemorrhoidalis (Bouche) (Thysanoptera: Thripidae), has increased on Chilean avocados as a consequence of the high value of the crop and the increased injury to the fruit surface. The population dynamics, phenology, and patterns of aggregation of H. haemorrhoidalis was determined with the objective of rationalizing the use of pesticides using a therapeutic control approach. The study was conducted in 2 avocado fields during 2005 to 2007 in the Valparaiso Region of Chile. New colonies developed on the leaves and small fruits, reaching greatest numbers at the beginning of the winter months. Immature stages were greater in number than the adults during most of the production season. The spatial distribution was calculated using Taylor's power law, showing an aggregated pattern with indices of 1.46 and 1.53 on leaves and fruits, respectively. Pooled data were used to describe the relationship between population density and the proportion of infested leaves and fruit. In the case of a density of about 2 thrips per leaf or fruit, the proportion of infested samples was 0.8. Sample size curves were generated as a function of mean density of thrips with about 20 presence/absence samples needed to estimate densities of 0.5 thrips or more at a precision level of 25%.

Pest management should be based on the proper identification of pests and knowledge of their biology. This publication describes the major pests of tomatoes, peppers, and eggplant in Florida and guidelines for their management. Some insects may be more important in some areas of the state than others. For each pest described, a table of management options will be found after the damage. Previous versions: Webb, S., P. Stansly, D. Schuster, and J. Funderburk. 2005. “Insect Management for Tomatoes, Peppers, and Eggplant”. EDIS 2005 (11). https://journals.flvc.org/edis/article/view/115118.

Frequent US port of entry quarantine interceptions of unidentifiable larval Leucothrips (Thysanoptera: Thripidae) species in association with Codiaeum variegatum (L.) Rumph. ex A. Juss. (Euphorbiaceae) ornamental plants from Costa Rica, initiated research to determine if these thrips were an invasive threat to US agriculture. Larval and adult Leucothrips were collected from the new growth leaves of C. variegatum and other plants in Florida and Costa Rica. There were no morphological differences among adult specimens from different hosts in Florida and Costa Rica; all identified as Leucothrips furcatus Hood by comparison with type specimens. However, morphological differences in larvae associated with these adult specimens were evident. DNA sequences of the mitochondrial cytochrome oxidase c subunit 1 gene (COI), and 2 regions of the nuclear ribosomal cistron (rRNA; the complete internal transcribed spacer 2 [ITS2], and a section of the 28S large subunit rRNA) were used to verify that larvae and a...

The western flower thrips, Frankliniella occidentalis (Pergande), is a polyphagous pest that has been spread worldwide. The extensive use of insecticides in attempts to control its populations eliminates natural enemies and competitor flower thrips species, thereby increasing its populations. An unsustainable situation develops with concomitant resistant pest populations, secondary pest outbreaks, and environmental degradation. Integrated pest management utilizes knowledge of pest and natural enemy relationships to implement tactics that are environmentally friendly and sustainable. Minute pirate bugs are the most important worldwide predators of thrips. They can suppress and ultimately control Frankliniella species flower thrips. Flower samples taken at least weekly are needed to understand predator-prey dynamics. Shown here is the sampling of the flowers of fruiting vegetables and companion plants to estimate the densities of individual thrips and minute pirate bug species. Representative data illustrates how the protocol is used to determine the efficacy of management tactics over time and how to evaluate the benefits of predation by minute pirate bugs. The sampling protocol is similarly adaptable to sampling thrips and minute pirate bugs in other plant species hosts.

A push-pull strategy for reducing populations of the thrips Frankliniella occidentalis (Pergande), F. bispinosa (Morgan) and F. tritici (Fitch) in tomato was evaluated. Push components consisted of ultraviolet (UV)-reflective mulch and foliar applications of kaolin and the pull component consisted of the companion plant Bidens alba (L.). Replicated field experiments were conducted in 2011 and 2012. Adult and larval thrips were reduced by UV-reflective mulch during early and mid-flowering of tomato. Spray applications of kaolin were effective in reducing adult and larval thrips during early, mid- and late-flowering. The pull effects of the B. alba companion plants were additive and sometimes interactive with the push effects of UV-reflective mulch and kaolin in reducing the adult males of each thrips species and the females of F. bispinosa. The strategy was not effective in reducing the adult females of F. tritici and F. occidentalis. In addition to attracting the Frankliniella species adults, the companion plants were hosts for the thrips predator Orius insidiosus (Say). The companion plants combined with UV-reflective mulch and kaolin proved effective as a push-pull system for suppressing flower thrips, including F. occidentalis which is a serious pest of tomato worldwide.

Few publications exist toward the identification of larval thrips. As a result, researchers and practitioners often are unable to report larval species data or may misinterpret what is a host plant when adults of multiple species are collected. Therefore, we conducted repetitive plant sampling and detailed examination of larvae with adults, which revealed morphological differences of some undescribed Frankliniella (Thysanoptera: Thripidae) larvae. The morphological differences were confirmed by non-destructive DNA extraction, PCR, and sequencing of the COI mitochondrial gene. A larva II morphological key to 7 Frankliniella species found in Florida is presented with new larval descriptions of 4 species.

Environmental factors are hypothesized to account for spatial and temporal differences in Florida in the abundance and distribution of the native thrips species Frankliniella bispinosa (Morgan) and the invasive Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae). Laboratory experiments were conducted at a constant temperature of 23 ± 1 °C to investigate the effects of humidity on the fecundity and egg incubation of F. bispinosa and F. occidentalis. Adult thrips were allowed to oviposit on green bean (Phaseolus vulgaris L.; Fabaceae) pods. Eggs were maintained at relative humidity treatment levels of 40 ± 5, 55 ± 5, 70 ± 5, and 80 ± 5%. Fecundity and time of egg hatch were determined every 12 h. Results showed that F. bispinosa had a higher fecundity and a shorter time to egg hatch compared with F. occidentalis at higher humidity levels. These results partially explained patterns of abundance and distribution of F. bispinosa and F. occidentalis in Florida. When relative humidity was hi...

Genomic and biological characterization of Tomato necrotic streak virus (TomNSV), a recently described ilarvirus infecting tomato in Florida, was completed. The full genome sequence revealed that TomNSV is a novel subgroup 2 ilarvirus that is distinct from other previously reported tomato-infecting ilarviruses: Tobacco streak virus, Parietaria mottle virus, and Tomato necrotic spot virus included in subgroup 1. In a host range experiment, TomNSV infected members of the Solanaceae and Chenopodiaceae plant families but did not infect sunflower (Helianthus annuus L.) or green bean (Phaseolus vulgaris L.). In tomato plants, the virus moved downward to the roots from the initial point of infection and then upward from the roots to tissues of active growth such as fruit, flowers, and young leaves where symptoms were produced. Thus, young leaves, fruit, and flowers are ideal for sampling for TomNSV. The transmission rate by seed collected from infected tomato plants was determined to be 0.33%. Collectively, the results of these experiments indicated that TomNSV is the causal agent of the necrotic streak disease of tomato observed in Florida since 2013.

Summary The African thrips Ceratothripoides brunneus Bagnall (Thysanoptera: Thripidae) is reported for the first time from North America, collected from flowers of Asystasia gangetica (L.) T. Anderson (Acanthaceae) in Miami-Dade County, Florida. The affinity of C. brunneus for solanaceous plants in other regions of the world suggests that future detection in Florida commercial tomato, pepper, and eggplant production areas is possible. A literature summary of geographic distribution and biology and a morphological description of adults are provided.

Typical tosposvirus symptoms, lateral flow immunoassay testing, and sequence data confirm this identification, which is therefore the first report of Tomato chlorotic spot virus infection of sweet basil and purslane in Florida and of the specific plant species from any location.

Frankliniella invasor is an important pest of mango in Central America; however, information is limited concerning the activity of insecticides with different modes of action. Eight insecticides representing 5 different chemical classes were assayed for control of F. invasor in Costa Rica. The spinosyns, spinetoram, and spinosad were highly active, whereas malathion and α-cypermethrin were the least active. The neonicotinoids imidacloprid and thiamethoxam resulted in intermediate toxicity to this thrips pest. Resumen Frankliniella invasor es una plaga importante del cultivo de mango en Costa Rica. Sin embargo, hasta la fecha se han publicado muy pocos ensayos de toxicologia en esta especie de trips. Se eligieron ocho insecticidas con diferentes modos de accion. Se realizaron dos ensayos toxicologicos consecutivos. Entre los insecticidas probados, las espinosinas (spinetoram y spinosad) fueron las mas eficientes. El malation, α-cipermetrina, fue el menos eficiente. Los neonicotinoides mostraron resultados diferentes con imidacloprid que no logro controlar la plaga F. invasor, y el tiametoxam dio un resultado toxicologico aceptable para esta especie. Key Words: mango; spinosyns; neonicotinoids; Central America View this article in BioOne

Groundnut ringspot virus (GRSV) and Tomato chlorotic spot virus (TCSV) are two emerging tospoviruses in Florida. In a survey of the southeastern United States, GRSV and TCSV were frequently detected in solanaceous crops and weeds with tospovirus-like symptoms in south Florida, and occurred sympatrically with Tomato spotted wilt virus (TSWV) in tomato and pepper in south Florida. TSWV was the only tospovirus detected in other survey locations, with the exceptions of GRSV from tomato (Solanum lycopersicum) in South Carolina and New York, both of which are first reports. Impatiens (Impatiens walleriana) and lettuce (Lactuca sativa) were the only non-solanaceous GRSV and/or TCSV hosts identified in experimental host range studies. Little genetic diversity was observed in GRSV and TCSV sequences, likely due to the recent introductions of both viruses. All GRSV isolates characterized were reassortants with the TCSV M RNA. In laboratory transmission studies, Frankliniella schultzei was a more efficient vector of GRSV than F. occidentalis. TCSV was acquired more efficiently than GRSV by F. occidentalis but upon acquisition, transmission frequencies were similar. Further spread of GRSV and TCSV in the United States is possible and detection of mixed infections highlights the opportunity for additional reassortment of tospovirus genomic RNAs.

Spanish moss, Tillandsia usneoides (L.) (Poales: Bromeliaceae), is widely distributed in the southeastern United States. A diversity of arthropod species from numerous taxa are known to inhabit this common epiphytic plant. Thysanoptera species inhabiting Spanish moss were sampled monthly over the course of a year from trees in 4 different genera and included 10 species of thrips from 8 genera and 3 families represented. Breeding populations of predatory Karnyothrips (Phlaeothripidae) were common in Spanish moss during all months of the year. The adults of 2 phytophagous species of Frankliniella (Thripidae) were common in the spring months, but only a few larvae were collected over the course of the year. The adults of other species collected were: Heterothrips quercicola J. C. Crawford (Heterothripidae); Chilothrips pini Hood, Neohydatothrips variabilis (Beach), and Selenothrips rubrocinctus (Giard) (Thripidae); and Hoplandrothrips pergandei Hinds and Liothrips ocellatus Hood (Phlaeothripidae). Although a diverse group of phytophagous thrips species inhabited Spanish moss, there was little evidence that it was a host. It may simply have been a temporary shelter with no other biological significance. The predatory thrips were abundant probably feeding on the diverse group of small arthropods that inhabit Spanish moss.

Mango cv. ‘Ataulfo’ is perhaps the most popular mango produced in Mexico. The presence of high densities of thrips in mango blossoms, mainly the species Frankliniella invasor Sakimura, has been linked to yield decline. Growers spray synthetic insecticides on a regular basis against thrips to reduce their numbers, but no studies on the effectiveness of these insecticides have been conducted. The present study was undertaken with the objective of assessing the toxicity of 4 insecticides commonly used by growers. Commercial formulations of spinosad, imidacloprid, malathion, and α-cypermethrin were evaluated on adults of F. invasor under laboratory conditions. Six concentrations of each insecticide were assessed: 0.1, 1, 10, 100, 1000, and 10,000 ppm. Snap bean pods were submerged into the different concentrations of insecticides, dried on paper towels, and placed in a plastic container with the thrips adults. A completely randomized design with 10 replicates per treatment was performed. Probit analyses revealed that spinosad and α-cypermethrin were the most toxic insecticides for F. invasor with estimated LC50 values of 0.413 and 0.636 ppm, respectively. No significant differences in toxicity were found between imidacloprid (LC50 = 23.013 ppm) and malathion (LC50 = 34.422 ppm). Mortality in control treatments (distilled water) was never higher than 14%. Our study suggests the use of spinosad and α-cypermethrin as the best control for F. invasor. However, these results should be complemented with field evaluations before being recommended to mango growers. El Mango cv. ‘Ataulfo’ es probablemente el mango mas popular de Mexico. La presencia de altas densidades de trips durante la floracion, principalmente de la especie Frankliniella invasor Sakimura, ha sido vinculada a la baja productividad. Los productores asperjan insecticidas sinteticos de forma regular contra los trips para reducir sus poblaciones, pero no se han llevado a cabo estudios sobre la efectividad de esos productos. El presente estudio se llevo a cabo con el objetivo de evaluar la toxicidad de cuatro insecticidas comunmente usados por los productores. Las formulaciones comerciales del espinosad, imidacloprid, malation, and α-cipermetrina fueron evaluados sobre adultos de F. invasor bajo condiciones de laboratorio. Fueron evaluadas seis concentraciones de cada insecticida: 0.1, 1, 10, 100, 1000, y 10,000 ppm. Para la evaluacion fueron utilizados ejotes, los cuales fueron sumergidos en diferentes concentraciones de insecticidas, secados en papel toalla, y colocados en contenedores de plastico con los trips adultos. Se utilizo un diseno completamente al azar con 10 replicas por tratamiento. El analisis Probit revelo que el espinosad y la α-cipermetrina fueron los insecticidas mas toxicos a F. invasor, con CL50 estimadas de 0.413 y 0.636 ppm, respectivamente. No se detectaron diferencias significativas entre imidacloprid (CL50 = 23.013 ppm) y malathion (CL50 = 34.422 ppm). La mortalidad en el control (agua destilada) no fue mas del 14% de los individuos. Nuestro estudio sugiere el uso del espinosad y la α-cypermethrin para el control de F. invasor. Sin embargo, estos resultados deberan ser complementados con pruebas de campo antes de ser recomendados a los productores. View this article in BioOne

Newer, selective insecticides with few negative impacts on natural enemies and competitor species are needed for effective, sustainable management of the western flower thrips, Frankliniella occidentalis (Pergande). The purpose of this study was to evaluate the impacts on natural enemies and competitor thrips species of insecticides used for control of western flower thrips in fruiting vegetables. Trials with tomato (Solanum lycopersicum L.) and with pepper (Capsicum annuum L.) were conducted to evaluate insecticide treatment effects on western flower thrips and natural enemies at the North Florida in 2008, 2009, 2010 and 2011. A number of insecticides from different classes showed moderate to high efficacy against western flower thrips. The broad-spectrum insecticides acetamiprid, methomyl, and tolfenpyrad demonstrated activity against the pest, while also reducing populations of the key predator of thrips in pepper, Orius insidiosus (Say) (Hemiptera: Anthocoridae). Insecticides that showed litt...

Summary Two Asian species of Thripidae are reported breeding in northern Florida on kudzu (Pueraria lobata), Salpingothrips aimotofus Kudo in the shoots, and Megalurothrips distalis Karny in the flowers, the latter being a new record for North America.

Cassava and cacao are 2 of the most important crops grown in Costa Rica, and also are major sources of income for rural farmers. These crops are frequently attacked by Corynothrips stenopterus Williams and redbanded thrips, Selenothrips rubrocinctus Giard (Thysanoptera: Thripidae). Most farmers who grow these crops apply synthetic insecticides on a calendar basis, but there are no well-established studies on the effectiveness or toxicity of different chemical insecticides on these species of thrips. The objective of this study was to determine the toxicity of 8 insecticides with different modes of action that are used in the control of other thrips species. Commercial formulations of chlorfenapyr, imidacloprid, chlorpyrifos, spinosad, malathion, thiamethoxam, spinetoram, and α-cypermethrin were evaluated on adults of both thrips species under laboratory conditions. Probit analyses showed that spinetoram, spinosad, and chlorfenapyr were the most effective against both thrips species, with median lethal dosages of 50% below 1 μg per mL for both species: 0.12, 0.08, and 0.21 μg per mL for C. stenopterus, and 6 × 10-3, 0.06, and 0.53 μg per mL for S. rubrocinctus . For the other 5 insecticides tested, C. stenopterus had a higher susceptibility than S. rubrocinctus . Among all the insecticides tested, malathion was the least efficacious against both thrips species. The mortality rate in the control treatments never exceeded 10%. The results of this study suggest that spinetoram, spinosad, and chlorfenapyr are the most efficacious insecticides for the control of both thrips species. These results should be complemented with field trials for confirmation. Resumen La yuca y el cacao son dos de los cultivos mas importantes que se siembran en Costa Rica y tambien son una importante fuente de ingresos para la mayoria de los agricultores rurales. Estos cultivos son atacados frecuentemente atacados por Corynothrips stenopterus Williams (yuca) y trips de banda roja Selenothrips rubrocinctus Giard (ambos Thysanoptera: Thripidae) (cacao). La mayoria de los agricultores que se dedican a la produccion de estos cultivos aplican insecticidas sinteticos con regularidad contra estos trips, pero no existen estudios bien establecidos sobre la efectividad o toxicidad de los diferentes insecticidas quimicos en estas especies de trips. Por lo tanto, se realizo el presente estudio con el objetivo de determiner la toxicidad de 8 insecticidas con diferentes modos de accion que se utilizan en el control de otras especies de trips. Las formulaciones comerciales de chlorfenapyr, imidacloprid, chlorpyrifos, spinosad, malathion, thiamethoxam, spinetoram y α-cipermetrina se evaluaron en adultos de ambas especies de trips en condiciones de laboratorio. Se usaron las siguientes 6 concentraciones de cada uno de los 8 insecticidas; 0, 1, 1.0, 10, 100, 1,000 y 10,000 ppm. Se utilizo un diseno completamente aleatorizado y cada tratamiento tuvo 5 repeticiones. Los analisis Probit mostraron que spinetoram, spinosad, y chlorfenapyr fueron los mas efectivos contra ambas especies de trips con LD50 por debajo de 1 μg por ml para ambas especies (0.12, 0.08 y 0.21 μg por mL) respectivamente para Corynothrips stenopterus y (6.10-3, 0.06 y 0.53 μg por mL) respectivamente para Selenothrips rubrocinctus . Los otros 5 insecticidas evaluados indicaron que C. stenopterus tenia una susceptibilidad mas alta que S. rubrocinctus . Entre todos los insecticidas probados, malathion fue el menos eficaz contra ambas especies de trips. La tasa de mortalidad en los tratamientos de control (con agua destilada) nunca excedio el 10%. Este estudio sugiere que spinetoram, spinosad, y chlorfenapyr son los mas eficientes para el control de ambas especies de trips. Sin embargo, estos resultados deberian completarse conensayos de campo para su confirmacion. View this article in BioOne

BACKGROUND:Thespreadofthewesternflowerthrips,Frankliniellaoccidentalis(Pergande)(Thysanoptera:Thripidae),resulted in the worldwide destabilization of established integrated pest management programs for many crops. Efforts to control the pest and the thrips-vectored tospoviruses with calendar applications of broad-spectrum insecticides have been unsuccessful. The result has been a classic ‘3-R’ situation: resistance to numerous insecticides; resurgence of the western flower thrips populationsasaresultofnaturalpredatorsandnativecompetitorthripsbeingeliminated;replacementbyvariousotherpests. Thispaperreportsonintegratedpestmanagementprogramsforfruitingvegetablesthatareeffective,economical,ecologically sound and sustainable. RESULTS: The components include the following: define pest status (economic thresholds); increase biotic resistance (natural enemiesandcompetition);integratepreventiveandtherapeutictactics(scouting,ultraviolet-reflectivetechnologies,biological control,compatibleinsecticides,companionplantsandfertility);verticallyintegratetheprogramswithotherpests;continually communicate latest science-based management tactics with end-users. CONCLUSION: These programs have been widely implemented in Florida and have significantly improved the management of western flower thrips and thrips-transmitted viruses. c � 2012 Society of Chemical Industry

‘Ataulfo’ mango (Mangifera indica L.) is the most popular cultivar of mango to have originated in Mexico. Because of its relatively recent discovery, few studies have been carried out on the best agricultural practices for production of this cultivar, and there is wide variation in methods among growers. Among other aspects, the insect fauna associated with this cultivar has not been formally studied. However, numerous growers spray synthetic insecticides on a regular basis against thrips to reduce populations. The present study was conducted with the main objective of determining the diversity of thrips in Ataulfo mango flowers in Chiapas, Mexico. Two representative orchards were selected: the orchard “Tres-A” characterized by an intensive use of agrochemicals, especially broad-spectrum synthetic insecticides directed against thrips, and the orchard “Rancho La Escondida” that does not spray insecticides. Inflorescences were sampled every five days, from Nov 2008 to Feb 2009. The results confirm ...

Tomato chlorotic spot virus (TCSV) has recently been detected in tomato, bell pepper, jimsonweed, and lettuce in Puerto Rico. Observations of weeds and additional crops in 2015 and 2016 revealed TCSV-like symptoms. Testing of these symptomatic plants identified three new hosts of TCSV in Puerto Rico: erect spiderling (Boerhavia erecta); Asian spiderflower (Cleome viscosa); and sweet chili pepper (Capsicum chinense).

The western flower thrips, Frankliniella occidentalis (Pergande); flower thrips, Frankliniella tritici (Fitch); and tobacco thrips, Frankliniella fusca (Hinds), are abundant, polyphagous species in the southern United States. Paspalum notatum Flugge and Paspalum distichum L. (Poales: Poaceae) are low-maintenance, warm-climate, tolerant grasses that are used for pasture and residential lawns and along roadsides. The potential of P. notatum and P. distichum to serve as sources of the common polyphagous Frankliniella thrips in the southeastern United States was evaluated. The abilities of F. fusca, F. occidentalis, and F. tritici to survive and reproduce on vegetative-stage P. distichum, P. notatum ‘Argentine’, P. notatum ‘Pensacola’, and P. notatum ‘Tifton 9’ were compared in laboratory no-choice tests. Survival of the adults of each thrips species was ≈20% after 12 d on each of the Paspalum treatments. No progeny were produced by F. occidentalis on the U.S. native P. distichum, and the other thrips species produced very few progeny on this host. The number of progeny of each thrips was very low on all P. notatum cultivars. A field survey of the Thysanoptera associated with P. notatum Argentine also was conducted to determine whether the Frankliniella thrips were feeding or reproducing under field conditions. A few male and female adults of F. tritici and F. fusca were noted in the racemes, but larval populations were not observed. Reproducing populations of Caprithrips insularis Beshear and Haplothrips graminis Hood were present in the stems and leaves, and the racemes, respectively. Collectively, the laboratory and field studies revealed that the tested P. notatum cultivars and P. distichum accession are poor hosts for reproduction of the Frankliniella thrips in the southern United States and that the large plantings of these grasses are not serving as sources of pest Frankliniella thrips.

Anthophilous flower thrips in the genus Frankliniella (Thysanoptera: Thripidae) exploit ephemeral plant resources and therefore must be capable of successfully locating appropriate hosts on a repeated basis, yet little is known of interspecific and intraspecific variation in responses to host plant type and nutritional quality. Field trials were conducted over two seasons to determine if the abundance of males and females of three common Frankliniella species, F. occidentalis (Pergande), F. tritici (Fitch) and F. bispinosa (Morgan), their larvae, and a key predator, Orius insidiosus (Say) (Hemiptera: Anthocoridae) were affected by host plant type and plant nutritional quality. Two host plants, pepper, Capsicum annuum L. (Solanales: Solanaceae) and tomato, Solanum lycopersicum L. that vary in suitability for these species were examined, and their nutritional quality was manipulated by applying three levels of nitrogen fertilization (101 kg/ha, 202 kg/ha, 404 kg/ha). F. occidentalis females were more abundant in pepper than in tomato, but males did not show a differential response. Both sexes of F. tritici and F. bispinosa were more abundant in tomato than in pepper. Larval thrips were more abundant in pepper than in tomato. Likewise, O. insidiosus females and nymphs were more abundant in pepper than in tomato. Only F. occidentalis females showed a distinct response to nitrogen fertilization, with abundance increasing with fertilization. These results show that host plant utilization patterns vary among Frankliniella spp. and should not be generalized from results of the intensively studied F. occidentalis. Given the different pest status of these species and their differential abundance in pepper and tomato, it is critical that scouting programs include species identifications for proper management.

Populations of the invasive Frankliniella occidentalis (Pergande) are serious pests of agricultural crops in the Aconcagua Valley of central Chile. An extensive survey was conducted of 55 plant species in 24 families to identify plant hosts of F. occidentalis and to determine its relative abundance on each host during each season. A more intensive study was conducted on selected plant species serving as reproductive hosts to determine the population dynamics of F. occidentalis and to evaluate the potential importance of Orius species and other natural enemies for controlling F. occidentalis. Adults of F. occidentalis were active during each season of the year inhabiting the flowers of 91% of the sampled plant species in 22 families, and 86% of these plant species in 19 families served as reproductive hosts. The number of host plant species used was greatest in the spring and least in the winter. All of the hosts except Medicago sativa L. were used only when flowering. Populations of F. occidentalis were significantly aggregated in M. sativa in the terminal buds over the leaves when the host was not flowering, and in the flowers, followed by the terminal buds, followed by the leaves when the host was flowering. Larvae were 1.3-2.3 times more abundant on dates when M. sativa was flowering. There were no identifiable patterns in plant hosts based on endemicity or plant family. Most of the plant species used by F. occidentalis were inferior quality hosts where populations either declined or were stable. Populations of F. occidentalis on low-quality hosts generally escaped predation by Orius species and competition by other species of thrips. Only 25% of the food hosts and 28% of the reproductive hosts for F. occidentalis in the extensive survey, respectively, were host plants for Orius. Parasitoids and other predators were not found to be important in suppressing thrips on any of the plant hosts. Populations of F. occidentalis increased on only a few hosts, including M. sativa and Sisymbrium officinale L. Scop. These apparently are major sources of F. occidentalis adults invading crops. We conclude that F. occidentalis is established in central Chile and that it has replaced and possibly displaced the native Frankliniella australis (Morgan) as the most common thrips species.

Feeding by the western flower thrips, Frankliniella occidentalis (Pergande), causes damage to the fruits of vegetables, and the species is the key vector of Tomato spotted wilt virus. Frankliniella tritici (Fitch) and Frankliniella bispinosa (Morgan) are not pests of fruiting vegetables. Both species compete with F. occidentalis. Effective management of F. occidentalis in pepper integrates conservation of natural populations of the predator, Orius insidiosus (Say), with the use of reduced-risk insecticides such as spinetoram for the control of western flower thrips and other pests. Naturally occurring O. insidiosus are very effective predators and their effectiveness is predictable based on the number of the predator relative to the number of thrips prey. Populations of F. occidentalis resurge when natural enemies and competing thrips are killed. Some insecticides especially pyrethroids have beneficial effects on the development and reproduction of F. occidentalis. The predator O. insidiosus does...

All parties involved in growing the world's food, including growers, crop consultants, university researchers, extension personnel, national and regional regulatory agencies, and the agrochemical and seed industry, spend significant time, money, and effort to solve the problems associated with growing food. The needs of these parties are varied and sometimes in conflict, which is not always conducive to developing and implementing integrated pest management (IPM) systems that are both sustainable and economical. IPM encompasses simultaneous management of multiple pests, regular monitoring of pests and their natural enemies and antagonists, use of economic or treatment thresholds when applying pesticides, and integrated use of multiple, suppressive tactics. IPM components with the greatest impact on resistance management are rotating classes of chemistry, use of recommended rates, not exceeding label restrictions, and avoiding sequential treatments of products with the same mode of action. The best way to insure that these components are followed is to have pesticide record keeping and reporting. However, pesticide use record keeping and reporting are not currently required in all areas. Other activities that can be integrated include educational workshops on IPM, resistance monitoring of pests to pesticides, proper identification of pests and natural enemies, real time scouting reports on the pests that are being found, maintenance of a data base on the effects of various products on natural enemies, and field validation of IPM use.

Invasive arthropods pose unique management challenges in various environments, the first of which is correct identification. This apparently mundane task is particularly difficult if multiple species are morphologically indistinguishable but accurate identification can be determined with DNA barcoding provided an adequate reference set is available. Scirtothrips dorsalis is a highly polyphagous plant pest with a rapidly expanding global distribution and this species, as currently recognized, may be comprised of cryptic species. Here we report the development of a comprehensive DNA barcode library for S. dorsalis and seven nuclear markers via next-generation sequencing for identification use within the complex. We also report the delimitation of nine cryptic species and two morphologically distinguishable species comprising the S. dorsalis species complex using histogram analysis of DNA barcodes, Bayesian phylogenetics, and the multi-species coalescent. One member of the complex, here designated the South Asia 1 cryptic species, is highly invasive, polyphagous, and likely the species implicated in tospovirus transmission. Two other species, South Asia 2, and East Asia 1 are also highly polyphagous and appear to be at an earlier stage of global invasion. The remaining members of the complex are regionally endemic, varying in their pest status and degree of polyphagy. In addition to patterns of invasion and endemism, our results provide a framework both for identifying members of the complex based on their DNA barcode, and for future species delimiting efforts.

Frankliniella occidentalis is the key vector responsible for the emergence of Tomato spotted wilt virus as a global threat to agriculture. Frankliniella bispinosa is a common thrips in Florida, the Bahamas, and Bermuda, but the role of F. bispinosa in the epidemiology of the virus is not known. The purpose of this study was to determine the ability of F. bispinosa to acquire and transmit Tomato spotted wilt virus in pepper. In laboratory experiments, the number of larvae produced per F. bispinosa female was less than the number of larvae produced per F. occidentalis female. The larvae of F. bispinosa successfully acquired Tomato spotted wilt virus, although at a lower percentage than F. occidentalis. Viruliferous adults of both species transmitted the virus to pepper. Our results confirm the competence of F. bispinosa as a vector of Tomato spotted wilt virus.

A biologically based integrated pest managefor pepper by Funderburk et al. (2000) and Reitz et ment program is fundamental in preventing al. (2003). Experimental design was a randomized the development of insecticide resistance, recomplete block, with 4 replications. Plot size was 1 surgence of populations of western flower thrips, raised, plastic mulched bed 9 m long on which there Frankliniella occidentalis (Pergande) (Thysanopwere 2 linear rows of pepper with a 13.8-cm plant tera: Thripidae), and replacement with nontarget spacing between and within rows for a total of 48 pest damage (Demirozer et al. 2012). The conservaplants per plot. Beds were irrigated with a single tion biological control component of the integrated trickle tube with emitters spaced every 30 cm at a pest management program is the most effective rate of 20,000 Ivha/day. Dates and rates of insecti way to manage thrips in pepper (Capsicum spp.; cide applications and of insect sampling are includ Solanales: Solanaceae) (Reitz et al. 2003). Species ed in Table 1. Foliar insecticides were applied with a of Anthocoridae are the most important worldwide C02-powered backpack sprayer equipped with 4 D7 predators of thrips. Within this family are minute nozzles with the amount of spray 430 L/ha. Drench pirate bugs with 2 species in Florida, Orius insidiotreatments were applied in a water solution of 200 sus (Say) and O. pumilio (Champion) (Hemiptera: mL/plant. Trickle tube treatments were applied in Anthocoridae). The minute pirate bugs are a valua water solution of 5.7 L/plot with a C02-powered able tool for controlling thrips as they prey preferinjector pressurized to 103 kPa, followed by 8 L of entially on the adults of the western flower thrips clean water rinse. Inline connectors with shut-off over the adults of the non-damaging native thrips valves were used to isolate the plots. Ten flowers species, F. tritici (Fitch) and F. bispinosa (Morgan) per plot (whenever possible) were collected on each (Baez et al. 2004). The damaging thrips larvae also of 6 sample dates and preserved in 70% alcohol with are preferred prey (Baez et al. 2004). About 1 minthe number of thrips and O. insidiosus determined ute pirate bug for every 180 thrips is sufficient for using 7 to 100 X magnification. The data for each suppression of the populations of thrips, and at a sample was converted to number per flower, pooled ratio of about 1 predator to 40 thrips, thrips populaover date, and transformed to log (x + 0.5) for anal tions are controlled (Funderburk et al. 2000). Natuysis of variance. When the overall treatment effect ral populations of minute pirate bug adults rapidly was significant at the P = 0.05 level, orthogonal invade pepper fields in sufficient numbers to control comparisons were used to separate treatment dif western flower thrips adults and larvae, but they ferences. Untransformed means per 10 flowers are must be conserved with judicious insecticide use reported in Table 1. (Funderburk et al. 2000, Demirozer et al. 2012). The adults of F. occidentalis and F. tritici ac An integrated pest management program for counted for 6 and 19% of the total thrips in the rm peppers that encompasses the simultaneous mantreated controls and there were no significant treat agement of multiple pests is being developed and ment differences (data not shown). The numbers of implemented (Demirozer et al. 2012). Ta further thrips were well below the economic thresholds es enhance the effectiveness of the conservation biotablished by Demirozer et al. (2012), with the ratio logical control component of this program, updated of predators in relation to prey sufficient in the cm information on insecticides labeled for fruiting vegtreated plots to result in thrips suppression. There etables against thrips or other pests that have little were treatment differences in the number of F. impact on populations of minute pirate bugs was bispinosa females, thrips larvae, and O. insidiosus reported (Funderburk et al. 2011). In the present nymphs (Table 1). When compared to the untreat report, imidacloprid 4.6SC (Bayer Crop Protection, ed control, 2 applications of cyantraniliprole 20SC Research Triangle Park, North Carolina) and cyanin the trickle tube did not reduce the numbers of traniliprole 10SE and 20SC (DuPont Crop Protecthrips or O. insidiosus in the flowers. However, the tion, Newark, Delaware) were evaluated against 2 applications of cyantraniliprole 20SC combined populations of thrips and minute pirate bugs, with a transplant treatment of imidacloprid 4.6SC Spinetoram SC (Dow AgroSciences, Indianapolis, resulted in 94, 82, and 88% reductions in numbers Indiana) was included as a standard foliar treatof F. bispinosa adults, thrips larvae, and O. insid ment. iosus nymphs, respectively. Unless there are unex Experimental procedures to evaluate the treatpected synergistic effects, this result showed that ment effects on adult and immature O. insidiosus the residual effect of a transplant application of and flower thrips were similar to those established imidacloprid lasted through pepper flowering and

Momol, M. T., Olson, S. M., Funderburk, J. E., Stavisky, J., and Marois, J. J. 2004. Integrated management of tomato spotted wilt on field-grown tomatoes. Plant Dis. 88:882-890. Epidemics of spotted wilt caused by Tomato spotted wilt virus (TSWV) vectored by Frankliniella occidentalis and possibly other thrips species occur regularly in tomato in the southeastern United States. Field experiments were conducted to determine the effects of UV-reflective mulch, acibenzolar-S-methyl (plant activator), and insecticides on progress of tomato spotted wilt incidence and population dynamics of flower thrips (including F. occidentalis, F. tritici, and F. bispinosa). Whole plots of tomatoes grown on UV-reflective and black polyethylene mulch were divided into subplots of acibenzolar-S-methyl and no acibenzolar-S-methyl, and subsubplots of insecticide and no insecticide for thrips control. The UV-reflective mulch was more effective than black polyethylene mulch each year in reducing colonization of thrips in May and the consequent primary infections of tomato spotted wilt. Application of acibenzolar-S-methyl further reduced tomato spotted wilt incidence in 2000 and 2002, when disease pressure was great. Reproduction of thrips on tomato was poor in these experiments, but their control in the insecticide-treated sub-subplots prevented secondary spread in both years. The combination of UV-reflective mulch, acibenzolar-S-methyl, and insecticides was very effective in reducing tomato spotted wilt incidence in tomato.

We compared predation of Orius insidiosus (Say) on adult and second instars of Frankliniella occidentalis (Pergande) and on adults of F. occidentalis and F. tritici (Fitch) in arenas with pepper flowers. Also, we compared the dispersal of these thrips in the presence and absence of the predator. For each experiment, two densities of thrips (10 and 20 total thrips) and two time exposures (10 and 34 h) were tested. Second instars were more likely to move from the flower where they were released than were F. occidentalis adults. F. tritici dispersed more than F. occidentalis. The presence of the predator enhanced movement by thrips from flowers in which they were released. Despite differences in prey movement, O. insidiosus successfully preyed on all types of prey that were offered. However, O. insidiosus appeared to deal differently with each type of prey. Predation of both larvae and adults was most likely to occur inside flowers. In trials with adults and second instars of F. occidentalis, larvae...

Summary Bittersweet nightshade, Solanum dulcamara L. (Solanales: Solanaceae), was sampled at numerous locations in Washington and Idaho. Adults of 8 species of thrips (Thysanoptera) from 3 families were collected, including the worldwide plant pests Frankliniella occidentalis (Pergande) and Thrips tabaci Lindeman (Thripidae), which are vectors of the serious plant viruses in the genus Tospovirus. Aeolothrips fasciatus Hinds (Aeolothripidae), a predator of small insects, also was collected.

We evaluated the within-plant distribution of Frankliniella spp. and the predator Orius insidiosus (Say) in pepper (Capsicum anuum L.), over a range of field conditions, and we conducted behavioral experiments to examine the time budgets of F. occidentalis (Pergande) and F. tritici (Fitch) females on pepper plant parts. In the field experiments Frankliniella species composition varied by season and location. Still, all populations of thrips and O. insidiosus in untreated and insecticide-treated pepper were highly concentrated in the flowers, with 82–99% of individuals of each taxa found in flowers. This preference for flowers was corroborated by laboratory-choice experiments. Adult females of F. occidentalis and F. tritici showed a strong preference for pepper flowers over leaves and buds. In laboratory observations, females of F. occidentalis spent 3.6× as much time on flowers as on all other plant parts, and females of F. tritici spent over 6.3× as much time on flowers as on all other plant par...

Thripinema khrustalevi (Chizov et al.) isolate Chile, a parasite of Frankliniella australis (Morgan), was collected from Cestrum parqui (L’Herit.) in the Aconcogua Valley of central Chile. Percent infection of males and females of F. australis by T. khrustalevi in the flowers of C. parqui was estimated biweekly for two years at three locations, including the La Campana National Park. Males were less infected than females. Numbers of F. australis adults and larvae in the flowers of C. parqui were greatest in the winter and early spring when parasitism of the adult females was low. Populations declined in late spring when parasitism was high. Parasitism remained high through the summer and fall, and populations of thrips remained very low. Highest parasitism of the females and males of F. australis was 84 and 60%, respectively.

Frankliniella fusca (Hinds) is a species of thrips that is a pest of peanuts and an important vector of tomato spotted wilt virus. In previous research, populations of thrips declined in peanut during midseason for unexplained reasons. Nematodes in the genus Thripinema are parasites of thrips that render infected females sterile. A new species, T. fuscum Tipping & Nguyen, was recently described as a parasite of F. fusca in peanut. In 1997 and 1998, the temporal changes in percent parasitism of F. fusca in plots of peanuts were determined. Parasitism of adult female thrips increased from an estimated 1% on seedling peanut each year to a maximum of 68% later in the 1997 growing season and 38% in the 1998 growing season. Treatments of several insecticides for control of thrips reduced percent parasitism of the females on most sample dates in 1997, but parasitism was not significantly affected in 1998. Estimates of the numbers of F. fusca in the flowers and terminal buds of peanuts declined each year as parasitism increased. The very high levels of parasitism in 1997 were associated with near extinction of larval populations of thrips during midseason. As a result, the spread of tomato spotted wilt virus by this vector species was reduced. Thus, T. fuscum may be an important natural enemy of F. fusca responsible for suppression of populations of thrips in peanut.

Watermelon and other cucurbits are important crops grown in Guatemala for local consumption and export. This is the first report of SqVYV infecting watermelon in Central America. Accepted for publication 14 July 2015. Published 15 July 2015.

Flower thrips, Frankliniella spp., are important pests of tomatoes, Lycopersicon esculentum Mill., throughout the mid-Atlantic region. Several species cause direct damage to the leaves and fruits, and species such as the western flower thrips (WFT), F occidentalis (Pergande), and the tobacco thrips, E fusca Hinds, also vector tomato spotted wilt virus (Zitter et al. 1989). Damage caused by F occidentalis to tomato can appear in several forms. In greenhouses, E occidentalis will feed on the leaves of young transplants, causing a spotting and desiccation of the leaves. Sclar (2000) states that E occidentalis are attracted to pollen sources, and will feed extensively on flower tissues and degrade flower quality. This results in reduced length of bloom and flower tissue damage. Salguero Navas et al. (1991) report that small indentations appear in tomato fruit from female oviposition, and these indentations are sometimes surrounded by a light-colored halo. This damage can result in rejection of fruit and lowering of grade. Although originally reported in the southwestern portion of the United States, WFT was first reported along the east coast in Georgia in 1981 (Beshear 1983). It is now present throughout the east coast, including New Jersey. Cosmetic damage to tomatoes, appearing as 'goldflecking' and or goldfleck rings on red tomatoes, began to occur simul

Today, the western flower thrips, Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae) is one of the most significant agricultural pests globally because of the damage it is able to inflict on a wide range of crops. Adults and larvae feed by piercing plant tissues with their needle-shaped mandible and draining the contents of punctured cells (reviewed in Kirk, 1997b). Feeding by adults and larvae produces scarring on foliage, flowers and fruits, which results in aesthetic crop damage and disrupts plant growth and physiology. Also, oviposition can produce a wound response in fruiting structures, which reduces the marketability of certain horticultural produce (Childers, 1997). Most importantly, western flower thrips is able to transmit several species of destructive plant viruses in the genus Tospovirus (Bunyaviridae). It is the most important vector of Tomato spotted wilt virus and Impatiens necrotic spot virus worldwide, and it is also known to vector Chrysanthemum stem necrosis virus, Groundnut ringspot virus and Tomato chlorotic spot virus (Pappu et al., 2009; Webster et al., 2011). The actual amounts of economic losses attributable to any pest are difficult to determine, but Goldbach and Peters (1994) estimated that Tomato spotted wilt virus alone caused over US$1 billion in losses annually on a global basis. This estimate did not include the direct damage caused by western flower thrips, and it still would further underestimate present day losses, as the western flower thrips has continued to spread throughout the world (Kirk & Terry, 2003; Reitz et al., 2011). The state of Georgia, USA compiles estimates of the economic costs of pests to its crops. These estimates include both crop losses and the costs of control measures. From 2001 – 2006, costs from thrips and TSWV for tomatoes (Solanum lycopersicum) and peppers (Capsicum annuum) have averaged over 12% of the harvested value of those crops per year (Sparks, 2003, 2004, 2005, 2006; Sparks & Riley, 2001, 2002). Over 60% of the total for economic losses from pests and control costs in tomato and pepper are from thrips and tomato spotted wilt virus (Sparks, 2003). In addition, losses in Georgia

Several invasive species of thrips have established in Florida and are causing serious economic losses to vegetable, ornamental, and agronomic crops. Damage to crops results from thrips feeding and egg-laying injury, by the thrips vectoring of plant diseases, the cost of using control tactics, and the loss of pesticides due to resistance. This 12-page fact sheet describes the biology and ecology of thrips and tomato spotted wilt virus, and recommends a management program. Written by Joe Funderburk, Stuart Reitz, Steve Olson, Phil Stansly, Hugh Smith, Gene McAvoy, Ozan Demirozer, Crystal Snodgrass, Mathews Paret, and Norm Leppla, and published by the UF Department of Entomology and Nematology, August 2011. ENY859/IN895: Managing Thrips and Tospoviruses in Tomato (ufl.edu)