Seasonal distribution of the ichthyofauna of Santa Ana National Wildlife Refuge, Alamo, Texas

This study investigated the small aquatic ecosystems of Santa Ana National Wildlife Refuge, located in a predominantly agricultural area of the Lower Rio Grande Valley, Texas. Fishes and water quality data were collected for 13 months to determine the status of fish populations and the factors which influence their distributions on the refuge. Sixteen fish species were collected during the study, however, more than 20 species are known to inhabit the Rio Grande in the vicinity of the refuge. Water source played a major role in influencing fish species richness in these aquatic ecosystems. Diverted river water offered the best source of fish species immigrants. Gambusia affinis, Cyprinodon variegatus, Menidia beryllina and Poecilia latipinna maintained relatively high abundances throughout the study. Gambusia affinis was the most abundant species collected from the refuge while C. variegatus contributed the greatest biomass. Fish abundance patterns were closely related to changes in water temperature

Catastro de poblaciones de insectos en siembras de Capsicum chinense L. en Georgetown, San Vicente, usando trampas CC modificadas.

The insect populations in hot pepper, Capsicum chinense L. (Solanaceae), were surveyed in Georgetown, St. Vincent, during the 2004 wet and 2005 dry seasons. Modified white, blue, and yellow CC traps were used to capture insects in the plantings. Overall, 69 insect families were captured, 41 of which were captured during both the wet and dry seasons. During the wet season, the greatest numbers of individuals captured were from the Cecidomyiidae, Chironomidae, Chloropidae, Chrysomelidae, Cicadellidae, and Drosophilidae families. During the dry season, the greatest numbers of individuals captured were from Chrysomelidae and Cicadellidae families. The addition of dichlorvos as a killing agent and propylene glycol as an insect preservative to the CC traps increased the number and diversity of insects caught. Additionally, propylene glycol helped to preserve the specimens for taxonomic and genetic determinations. CC traps with yellow bases attracted more insect families than traps with white or blue bases. However, CC traps with blue bases caught more Lonchaeidae during both the wet and dry seasons, and more Tachinidae during the dry season. CC traps with white or yellow trap bases were equally attractive to insects in the families Aleyrodidae, Drosophilidae, Lauxaniidae, and Otitidae.Las poblaciones de insectos en el ají picante, Capsicum chinense L., se monitorearon en Georgetown, San Vicente, durante la época de lluvia de 2004 y la de sequía de 2005. Se usaron las trampas CC modificadas, blancas, azules y amarillas, para capturar insectos en las siembras. Se capturaron 69 familias de insectos; 41 de éstas se capturaron durante ambas épocas, la de lluvia y la de sequía. Durante la época de lluvia, el mayor número de individuos capturados pertenecía a las familias Cecidomyiidae, Chironomidae, Chloropidae, Chrysomelidae, Cicadellidae y Drosophilidae. Durante la época de sequía, el mayor número de individuos capturados pertenecía a las familias Cicadellidae y Chrysomelidae. El número y la diversidad de los insectos capturados aumentaron al añadir dichlorvos como un agente exterminador y glicol de propileno como agente preservativo a las trampas CC. Además, el glicol de propileno ayudó a preservar los especímenes para las determinaciones taxonómicas y genéticas. Las trampas CC con bases amarillas atrajeron más familias de insectos que las trampas con bases blancas o azules. Sin embargo, las trampas CC con bases azules capturaron más Lonchaeidae durante ambas épocas, de lluvia y sequía, y más Tachinidae durante la época de sequía. Las trampas CC con bases blancas o amarillas resultaron igualmente atractivas a los insectos en las familias Aleyrodidae, Drosophilidae, Lauxaniidae y Otitidae

Screening commercial entomopathogenic fungi for the management of Diaphorina citri populations in the Lower Rio Grande Valley, Texas, USA

Ten strains of entomopathogenic ascomycete fungi, sourced from commercial formulations of blastopore or conidiospore formulations, were tested in 14 different formulations in a primary acquisition/direct spray bioassay against adult Asian citrus psyllid (Diaphorina citri Kuwayama (Hemiptera: Liviidae)). The Cordyceps (Isaria) javanica Apopka 97-C (conidia) strain was used as the standard. A statistical ranking system was established in which top performing pathogenic strains were selected for further screening and eventual field trials. Modified Potter-type spray towers were utilized to deliver a range of doses of viable spores to adult D. citri in an aqueous spray consistent with the rate of spores per hectare often used in real-world spray applications. Mortality was assessed after a seven-day incubation period under controlled climate conditions reflecting those in the Lower Rio Grande Valley (LRGV) of Texas, USA. Of the 14 preparations, the strains Metarhizium anisopliae E9, C. fumosorosea Ifr9901, Beauveria bassiana ATCC 74040 and ANT-03, M. anisopliae ESALQ1037, and M. robertsii DWR2009, showed greater levels of mortality than the standard, Apopka 97-C, in the laboratory setting. Of those six, two (Ifr9901 and ANT-03) were selected for further evaluation based on efficacy, commercial availability, geographical registration, and market outlook on production

Assessment of Two Novel Host-Derived Beauveria bassiana (Hypocreales: Cordycipitaceae) Isolates Against the Citrus Pest, Diaphorina citri (Hemiptera: Liviidae)

The Asian citrus psyllid (ACP), Diaphorina citri Kuwayama (Hemiptera: Liviidae), vectors ‘Candidatus Liberibacter spp.’, the causative agent of Citrus Greening Disease (CGD) or Huanglongbing (HLB). Managing populations of psyllids in the Lower Rio Grande Valley (LRGV), TX, United States is imperative given a continuous increase in HLB-positive trees. A component of integrated pest management (IPM) program is the use of strains of entomopathogenic fungi for the biological control of D. citri. In an attempt to find endemic strains of entomopathogenic fungi that grow favorably under LRGV environmental conditions and naturally infect D. citri, psyllids were collected from local residential areas, surface sterilized, and plated on a semi-selective agar medium. Collection of over 9,300 samples from 278 sites throughout the LRGV led to the positive identification of two Beauveria bassiana (Balsamo-Crivellii) Vuillemin (Hypocreales: Cordycipitaceae) isolates, ACP18001 and ACP18002. Chi-square analysis of primary and secondary acquisition bioassays revealed that both field isolated strains outperformed Cordyceps (Isaria) fumosorosea (Wize) (Hypocreales: Cordycipitaceae) Apopka97 under both primary (direct spray) and secondary acquisition (adult exposure to sprayed foliage) bioassays with ACP18002 marginally outperforming ACP18001 under secondary acquisition. Slopes of the dose response regression lines for the three fungi were not significantly different. In addition, the thermal profiles for vegetative growth of each isolate indicated that the field isolates grew at higher rates than the standard at higher temperatures. The new isolates may prove to be good candidates for the management of D. citri populations in the LRGV

Complex of primary and secondary parasitoids (Hymenoptera: Encyrtidae and Signiphoridae) of Hypogeococcus spp. Mealybugs (Hemiptera: Pseudococcidae) in the New World

Se informan los resultados de los relevamientos de los parasitoides primarios y secundarios (hiperparasitoides) de Hypogeococcus spp. (Hemiptera: Pseudococcidae) realizados en el Nuevo Mundo durante el período 2009 para 2017 para obtener enemigos naturales de la cochinilla harinosa de los cactus (Harrisia cactus mealybug) Hypogeococcus sp., que está devastando cactus nativos en Puerto Rico y amenaza a los cactus presentes en Islas del Caribe adyacentes. Se registraron cinco especies de Encyrtidae (Hymenoptera: Chalcidoidea) como parasitoides primarios de Hypogeococcus spp., incluyendo el recientemente descrito Leptomastidea hypogeococci Triapitsyn sp. n., que es la única especie del género Leptomastidea García Mercet en el Nuevo Mundo cuya clava de la antena de la hembra es contrastantemente blanca. El análisis genético de los individuos de L. hypogeococci de Argentina, Brasil y Puerto Rico (EE. UU.) corrobora los datos morfológicos de que la misma especie se encuentra en América del Sur, las islas del Caribe y Florida (EE. UU.). Se proporciona una clave para las especies del Nuevo Mundo de Leptomastidea. Leptomastidea antillicola Dozier, syn. n. de Puerto Rico es sinonimizado bajo L. abnormis (Girault). Basado en los datos moleculares presentados, Anagyrus ciomperliki Triapitsyn syn. n. (Encyrtidae), originalmente descrito de Puerto Rico, es sinonimizado bajo A. quilmes Triapitsyn, Logarzo & Aguirre, cuyo rango de distribución conocido también se amplía para incluir a Brasil. Anagyrus cachamai Triapitsyn, Logarzo y Aguirre, A. lapachosus Triapitsyn, Aguirre y Logarzo y A. quilmes se registraron recientemente en Paraguay. Se describe el macho previamente desconocido de Prochiloneurus argentinensis (De Santis) (Encyrtidae) de la provincia de Misiones de Argentina, y el de P. narendrani Noyes & Triapitsyn de la Isla de Mona, Puerto Rico. Hasta aquí, Anagyrus cachamai y A. lapachosus se consideran como las principales especies para la introducción desde Argentina y Paraguay a Puerto Rico para el control biológico de la cochinilla harinosa de los cactus. El holotipo de Anagyrus tanystis De Santis de Buenos Aires, Argentina, cuyos hospederos asociados son desconocidos, se ilustra para facilitar su reconocimiento de otras especies congenéricas.Parasitoids, both primary and secondary (hyperparasitoids), of Hypogeococcus spp. mealybugs (Hemiptera: Pseudococcidae) are reviewed to report results of the surveys in the New World conducted during 2009 to 2017 for prospective natural enemies of the Harrisia cactus mealybug, Hypogeococcus sp., which is devastating native cacti in Puerto Rico and threatening cacti in the adjacent Caribbean islands. Five species of Encyrtidae (Hymenoptera: Chalcidoidea) are recorded as primary parasitoids of Hypogeococcus spp., including the newly described Leptomastidea hypogeococci Triapitsyn sp. n., which is the only species of the genus Leptomastidea García Mercet in the New World where the clava of the female antenna is contrastingly white. Genetic analysis of the individuals of L. hypogeococci from Argentina, Brazil, and Puerto Rico (USA) corroborates the morphological data that the same species occurs in South America, the Caribbean islands, and Florida (USA). A key to the New World species of Leptomastidea is given and taxonomic notes are provided on its other known species in the Neotropical region. Leptomastidea antillicola Dozier, syn. n. from Puerto Rico is synonymized under L. abnormis (Girault). Based on the presented molecular data, Anagyrus ciomperliki Triapitsyn syn. n. (Encyrtidae), originally described from Puerto Rico, is synonymized under A. quilmes Triapitsyn, Logarzo & Aguirre, where the known distributional range is expanded to also include Brazil. Anagyrus cachamai Triapitsyn, Logarzo & Aguirre, A. lapachosus Triapitsyn, Aguirre & Logarzo, and A. quilmes are newly recorded from Paraguay. The previously unknown male of Prochiloneurus argentinensis (De Santis) (Encyrtidae) is described from Misiones Province of Argentina, and that of P. narendrani Noyes & Triapitsyn is described from Mona Island, Puerto Rico. So far, Anagyrus cachamai and A. lapachosus are considered to be the primary target species for introduction from Argentina and Paraguay into Puerto Rico for the biological control of Harrisia cactus mealybug. The holotype of Anagyrus tanystis De Santis from Buenos Aires, Argentina, host associations are unknown, and is illustrated to facilitate its recognition from other congeneric species.Fil: Triapitsyn, Serguei V.. University of California; Estados UnidosFil: Aguirre, María Belén. Fundación para el Estudio de Especies Invasivas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Logarzo, Guillermo Alejandro. Fundación para el Estudio de Especies Invasivas; ArgentinaFil: Hight, Stephen D.. United States Department of Agriculture. Agriculture Research Service; Estados UnidosFil: Ciomperlik, Matthew A.. United States Department of Agriculture. Agriculture Research Service; Estados UnidosFil: Rugman Jones, Paul F.. University of California; Estados UnidosFil: Rodrigues, Jose C. Verle. Universidad de Puerto Rico; Puerto Ric

Characterization and separation of indigenous and exotic populations of Diaeretiella rapae (M'intosh) (Hymenoptera : Aphidiidae)

Vita.Laboratory experiments were designed to identify distinct biological attributes that might separate and help clarify the taxonomic status of one indigenous and six exotic populations of Diaeretiella rapae (M'Intosh). Experiments were conducted to investigate courtship and mating behaviors, host remains characters, host aphid acceptability and suitability, genetic differences, and reproductive isolation among the D. rapae populations. Parasite cultures in this research were selected from those imported and cultured for control of Russian wheat aphid (RWA), Diuraphis noxia (Mordvilko). Observations of mating behavior among D. rapae populations showed a series of distinct components. Qualitative observations and quantitative analyses of the mating behavior components did not distinguish behaviors that could reliably separate the D. rapae populations. Host remains characters including exit hole shape and location, and mummy coloration, could not be used to separate the D. rapae populations. RWA mummy dissections showed no differences among populations regarding shape or color of meconial pellets. Significant differences were determined in the mean number of meconial pellets produced by different parasite populations. However, the magnitude of difference was insufficient for distinct separation of one population from another. Host aphid acceptability and suitability experiments differentiated between three parasite populations based on their unique ability to parasitize a particular host aphid. The Syrian, Spain, and Jordan populations were distinctive because they could develop on cotton aphid, crape myrtle aphid, and yellow pecan aphid, respectively; while the other populations could not. Twenty three enzymes surveyed with starch gel electrophoresis revealed twenty eight distinct loci, and six of these were polymorphic among D. rapae populations. None of the identified loci showed fixed allelic differences between the populations. Analyses of isozyme polymorphism data, using Nei's and Rodger's genetic distance, indicated that the populations were genetically very similar. Reciprocal cross experiments between D. rapae populations showed varying levels of either complete reproductive compatibility, or one- or two-way partial isolation between some D. rapae populations. No cases of complete reproductive isolation were observed. Collectively, these observations indicate that the Syrian, Spain, and Jordan populations of D. rapae are biotypes, and the other populations are geographical strains

Characterization and separation of indigenous and exotic populations of Diaeretiella rapae (M'intosh) (Hymenoptera : Aphidiidae)

Vita.Laboratory experiments were designed to identify distinct biological attributes that might separate and help clarify the taxonomic status of one indigenous and six exotic populations of Diaeretiella rapae (M'Intosh). Experiments were conducted to investigate courtship and mating behaviors, host remains characters, host aphid acceptability and suitability, genetic differences, and reproductive isolation among the D. rapae populations. Parasite cultures in this research were selected from those imported and cultured for control of Russian wheat aphid (RWA), Diuraphis noxia (Mordvilko). Observations of mating behavior among D. rapae populations showed a series of distinct components. Qualitative observations and quantitative analyses of the mating behavior components did not distinguish behaviors that could reliably separate the D. rapae populations. Host remains characters including exit hole shape and location, and mummy coloration, could not be used to separate the D. rapae populations. RWA mummy dissections showed no differences among populations regarding shape or color of meconial pellets. Significant differences were determined in the mean number of meconial pellets produced by different parasite populations. However, the magnitude of difference was insufficient for distinct separation of one population from another. Host aphid acceptability and suitability experiments differentiated between three parasite populations based on their unique ability to parasitize a particular host aphid. The Syrian, Spain, and Jordan populations were distinctive because they could develop on cotton aphid, crape myrtle aphid, and yellow pecan aphid, respectively; while the other populations could not. Twenty three enzymes surveyed with starch gel electrophoresis revealed twenty eight distinct loci, and six of these were polymorphic among D. rapae populations. None of the identified loci showed fixed allelic differences between the populations. Analyses of isozyme polymorphism data, using Nei's and Rodger's genetic distance, indicated that the populations were genetically very similar. Reciprocal cross experiments between D. rapae populations showed varying levels of either complete reproductive compatibility, or one- or two-way partial isolation between some D. rapae populations. No cases of complete reproductive isolation were observed. Collectively, these observations indicate that the Syrian, Spain, and Jordan populations of D. rapae are biotypes, and the other populations are geographical strains

Biological control agents of cotton pests in Barbados

Cotton, Gossypium barbadense L (Malvaceae) is attacked by different insects, reducing  productivity and fibre quality. This study aimed to determine the natural enemies attacking the key cotton pests in Barbados. Seventeen farms were monitored weekly during  cotton seasons to determine presence of predators and parasitoids. The monitoring method used was zig-zag evaluating 25 plants in each location. The different stages of the predators presented at the field level were observed and evaluated. Attacked eggs of Lepidoptera and larvae having external parasitoids were collected and isolated to study the endo- and ectoparasitoid species. In addition to the natural enemie’s evaluation, a study was carried out at the field level selecting 10 farmers in order to evaluate the main pest found that leaded to the application of chemical control. Seven predator species and two parasitoid species were found. The most frequent predator species were Chrysoperla sp. (40 %), followed by Cycloneda sanguinea (L). and Allograpta exotica Wiedemann (15 % and 14.5 %, respectively). Parasitoid species found were: Trichogramma chilonis (Ishii) parasitizing Helicoverpa and Heliothis eggs, and Euplectrus sp. as an ectoparasitoid on Alabama argillacea larvae

Biological control agents of cotton pests in Barbados

Cotton, Gossypium barbadense L (Malvaceae) is attacked by different insects, reducing  productivity and fibre quality. This study aimed to determine the natural enemies attacking the key cotton pests in Barbados. Seventeen farms were monitored weekly during  cotton seasons to determine presence of predators and parasitoids. The monitoring method used was zig-zag evaluating 25 plants in each location. The different stages of the predators presented at the field level were observed and evaluated. Attacked eggs of Lepidoptera and larvae having external parasitoids were collected and isolated to study the endo- and ectoparasitoid species. In addition to the natural enemie’s evaluation, a study was carried out at the field level selecting 10 farmers in order to evaluate the main pest found that leaded to the application of chemical control. Seven predator species and two parasitoid species were found. The most frequent predator species were Chrysoperla sp. (40 %), followed by Cycloneda sanguinea (L). and Allograpta exotica Wiedemann (15 % and 14.5 %, respectively). Parasitoid species found were: Trichogramma chilonis (Ishii) parasitizing Helicoverpa and Heliothis eggs, and Euplectrus sp. as an ectoparasitoid on Alabama argillacea larvae