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Agronomy, agriculture, phytopathology, Agronomie, agriculture, phytopathologie, Entomology, Entomologie, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, and Fundamental and applied biological sciences. Psychology

The effects of secondary metabolites in different Vigna species on the development of Clavigralla tomentosicollis were investigated in an artificial seed system using different fractions of crude pod extracts, while the orientation response of this pod-bug to volatile extracts was studied using a dual-choice olfactometer. Feeding on the neutral fraction extracts, in contrast to the basic and acidic fractions, resulted in significantly higher mortalities, longer total developmental time, and lower growth index of the insects in comparison with controls. All volatile extracts elicited an avoidance reaction by C. tomentosicollis, except the volatile from the susceptible genotype IT84S-2246 which generally attracted as many insects as controls. Extracts from wild Vigna species showed higher activity than those from their cultivated relatives. The present study which has established that most secondary metabolites in cowpea pods were localized in the neutral fraction of the crude extract, could facilitate experiments on the separation and characterization of the toxic factors involved.

Agronomy, agriculture, phytopathology, Agronomie, agriculture, phytopathologie, Entomology, Entomologie, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Phytopathologie. Zoologie agricole. Protection des cultures et des forets, Phytopathology. Animal pests. Plant and forest protection, Protozoaires. Invertébrés, Protozoa. Invertebrates, Signalements, symptômes, dégâts, importance économique, surveillance des populations, Records, symptoms, damages, economic importance, population surveys, Angiospermae, Arthropoda, Coreidae, Dicotyledones, Déprédateur, Pest, Plaga, Heteroptera, Insecta, Invertebrata, Leguminosae, Légumineuse grain, Grain legume, Leguminosa grano, Relation animal végétal, Animal plant relation, Relación animal vegetal, Spermatophyta, Comportement alimentaire, Feeding behavior, Conducta alimenticia, Comportement déprédateur, Pest behavior, Conducta depredadora, Culture tropicale, Tropical crop, Cultivo tropical, Cycle développement, Life cycle, Ciclo desarrollo, Etude en laboratoire, Laboratory study, Estudio en laboratorio, Glycine max, Hôte substitution, Host substitution, Huesped sustitución, Plante hôte, Host plant, Planta huesped, Survie, Survival, Sobrevivencia, Vigna unguiculata, and Clavigralla tomentosicollis

Suitability of the pods of cowpea (Vigna unguiculata (L.) Walp) and soybean (Glycine max (L.) Merrill) as food for Clavigralla tomentosicollis was determined in the laboratory using development, food substitution and host switch experiments. On soybean pods, nymphs survived for 8 days and adults for 12 days; on cowpea, all nymphal instars developed into adults and lived for 80-100 days. Teneral adults that were switched from cowpea to soybean lost weight, while adults that were moved from soybean to cowpea gained weight with slight differences between the sexes. The shortest critical survival threshold (duration with at least 50% survival) of adults on cowpea was greater than the longest on soybean. The likelihood of C. tomentosicollis exploiting soybean as a trophic niche in areas of tropical Africa where production of this crop is on the increase and usually contiguous with cowpea production, is discussed.

Agronomy, agriculture, phytopathology, Agronomie, agriculture, phytopathologie, Entomology, Entomologie, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Agronomie. Sciences du sol et productions vegetales, Agronomy. Soil science and plant productions, Génétique et amélioration des plantes d'intérêt économique, Genetics and breeding of economic plants, Sélection variétale. Amélioration spéciale, objectifs d'amélioration, Varietal selection. Specialized plant breeding, plant breeding aims, Résistance aux organismes nuisibles, Pest resistance, Déprédateurs, Pest animals, Amélioration génétique, Genetic improvement, Enriquecimiento genético, Angiospermae, Arthropoda, Coreidae, Culture tropicale, Tropical crop, Cultivo tropical, Dicotyledones, Déprédateur, Pest, Plaga, Fruit, Fruto, Heteroptera, Insecta, Invertebrata, Leguminosae, Légumineuse grain, Grain legume, Leguminosa grano, Plante sauvage, Wild plant, Planta salvaje, Spermatophyta, Comparaison interspécifique, Interspecific comparison, Comparación interespecífica, Cultivar, Dégât, Damage, Estrago, Effet dimensionnel, Size effect, Efecto dimensional, Etude en laboratoire, Laboratory study, Estudio en laboratorio, Gousse, Pod, Vaina, Graine, Seeds, Semillas, Infestation, Infestación, Lignée sélection, Breeding line, Línea selección, Mécanisme défense, Defense mechanism, Mecanismo defensa, Ressource génétique, Genetic resource, Recurso genético, Résistance insecte, Insect resistance, Resistencia insecto, Trichome, Tricoma, Vigna unguiculata, Clavigralla tomentosicollis, Péricarpe, Pericarp, and Vigna vexillata

Studies were conducted in the laboratory to investigate the different components of the resistance of Vigna vexillata A. Richards, TVnu 72, and several cultivars of cultivated Vigna spp. to infestation and damage by the brown cowpea coreid, Clavigralla tomentosicollis Stäl. The main objective was to determine the different roles of the pod wall and seeds, and the relationship between seed size, number, and damage by this insect. Results showed that both the pod wall and seed clearly contribute different components to the resistance of TVnu 72 to C. tomentosicollis. Analysis of the results suggests that the seed defences and the pod wall pericarp may be more important than are trichomes in this resistance. Seed number was found to influence the extent of damage in a more predictable manner than seed size. However, because both of these traits are generally inversely related and mutually exclusive, their individual effects cannot be completely separated. The implications of these traits in a breeding programme targeted at a specific consumer group are discussed.

Agronomy, agriculture, phytopathology, Agronomie, agriculture, phytopathologie, Entomology, Entomologie, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Invertebres, Invertebrates, Ecologie animale, vegetale et microbienne, Animal, plant and microbial ecology, Ecologie animale et végétale, Animal and plant ecology, Autoécologie, Autoecology, Animaux, Animals, Protozoa. Invertebrata, Angiospermae, Arthropoda, Dicotyledones, Heteroptera, Insecta, Invertebrata, Leguminosae, Spermatophyta, Déprédateur, Pest, Plaga, Développement, Development, Desarrollo, Etude en laboratoire, Laboratory study, Estudio en laboratorio, Fécondité, Fecundity, Fecundidad, Lens culinaris, Longévité, Longevity, Longevidad, Pentatomidae, Pisum sativum, Plante hôte, Host plant, Planta huesped, Plante légumière, Vegetable crop, Planta leguminosa, Relation animal végétal, Animal plant relation, Relación animal vegetal, Reproduction, Reproducción, and Thyanta pallidovirens

Agronomy, agriculture, phytopathology, Agronomie, agriculture, phytopathologie, Entomology, Entomologie, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Agronomie. Sciences du sol et productions vegetales, Agronomy. Soil science and plant productions, Génétique et amélioration des plantes d'intérêt économique, Genetics and breeding of economic plants, Sélection variétale. Amélioration spéciale, objectifs d'amélioration, Varietal selection. Specialized plant breeding, plant breeding aims, Résistance aux organismes nuisibles, Pest resistance, Déprédateurs, Pest animals, Africa, Angiospermae, Arthropoda, Dicotyledones, Heteroptera, Insecta, Invertebrata, Leguminosae, Spermatophyta, Afrique, Coreidae, Criblage, Screening, Cernido, Déprédateur, Pest, Plaga, Etude en laboratoire, Laboratory study, Estudio en laboratorio, Etude en serre, Greenhouse study, Estudio en invernadero, Etude sur terrain, Field study, Estudio en campo, Lignée sélection, Breeding line, Línea selección, Méthode, Method, Método, Méthodologie, Methodology, Metodología, Nigéria, Nigeria, Origine végétale, Plant origin, Origen vegetal, Plante légumière, Vegetable crop, Planta leguminosa, Relation animal végétal, Animal plant relation, Relación animal vegetal, Résistance insecte, Insect resistance, Resistencia insecto, Sensibilité résistance, Sensitivity resistance, Sensibilidad resistencia, Vigna unguiculata, Pest resistance, Clavigralla tomentosicollis, and Résistance déprédateur

Description des procédures de criblage destinées à tester la résistance de nouvelles accessions de niébé, et qui peuvent être appliquées pour le criblage rapide de germoplasmes et la séparation des lignées de sélection.

Agronomy, agriculture, phytopathology, Agronomie, agriculture, phytopathologie, Ecology, Ecologie, Entomology, Entomologie, Environment, Environnement, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Ecologie animale, vegetale et microbienne, Animal, plant and microbial ecology, Ecologie appliquée, Applied ecology, Ecotoxicologie, effets biologiques de la pollution, Ecotoxicology, biological effects of pollution, Action de la pollution et effets secondaires des pesticides sur les protozoaires et les invertébrés, Effects of pollution and side effects of pesticides on protozoa and invertebrates, Phytopathologie. Zoologie agricole. Protection des cultures et des forets, Phytopathology. Animal pests. Plant and forest protection, Protozoaires. Invertébrés, Protozoa. Invertebrates, Généralités, Generalities, Lutte, Control, Angiospermae, Arachnida, Arthropoda, Gramineae, Insecta, Invertebrata, Monocotyledones, Spermatophyta, Acephate, Araneida, Carbophenothion, Cypermethrine, Cyrthorhinus lividipennis, Delphacidae, Deltamethrine, Dose létale 50, Lethal dose 50, Dosis letal 50, Déprédateur, Pest, Effet secondaire, Secondary effect, Efecto secundario, Endosulfan, Entomophage, Entomophagous, Entomofago, Ethylan, Heteroptera, Homoptera, Insecticide, Lycosa pseudoannulata, Microvelia atrolineata, Nilaparvata lugens, Oryza sativa, Osbac, Plante céréalière, Cereal crop, Prédateur, Predator, Predador, Toxicité, Toxicity, and Toxicidad

Entomology, Entomologie, Tropical medicine, Médecine tropicale, Parasitology, Parasitologie, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Invertebres, Invertebrates, Insecta, Vecteurs d'importance medicale, nuisances, depredateurs des denrees et materiaux: surveillance des populations et lutte, Medically important nuisances and vectors, pests of stored products and materials: population survey and control, Vecteurs. Hôtes intermédaires, Vectors. Intermediate hosts, Sciences medicales, Medical sciences, Pathologie infectieuse, Infectious diseases, Parasitoses, Parasitic diseases, Protozooses, Protozoal diseases, Protozooses humaines, Human protozoal diseases, Trypanosomiase, Trypanosomiasis, Arthropoda, Infection, Infección, Invertebrata, Parasitose, Parasitosis, Protozoose, Protozoal disease, Protozoosis, Trypanosomiase, Trypanosomiasis, Tripanosomiasis, Abondance, Abundance, Abundancia, Allergie, Allergy, Alergia, Dispersion, Dispersión, Insecta, Potentiel vecteur, Vector potential, Potencial vector, Trypanosomiase américaine, Chagas disease, Tripanosomiasis americana, U.S.A, allergy, dispersal, and triatomine

Triatomine insects are a problem for human health in southwestern United States because of the moderate-to-severe allergic reactions their bites can cause and because they are potential vectors of Chagas Disease. Although both infected insects and wild mammalian reservoirs are plentiful in southern U.S., only seven cases of autochthonous transmission (plus 16 new presumed cases) of this disease have been reported to date. Therefore, the purpose of this study was to investigate triatomine distribution and abundance in a metropolitan area in southern Arizona. Species, life-stage, locality, and date of collection were recorded for 1,878 triatomine insects collected during 4 yr inside and around houses. For both sexes of the most abundant species, Triatoma rubida (Uhler) (>95% of triatomines collected), dispersal followed a typical year-to-year pattern: dispersal started at the beginning of May and peaked during the first-second week of June. T. rubida was found widely distributed in suburban areas. Triatomines of the two less abundant species, T recurva (Stal) and T. protracta (Uhler), were collected in all suburban areas throughout the 4-yr survey. All of these population characteristics were observed both at a large (i.e., all collection sites pooled) and a small (i.e., single collection sites) scale. In total, ≈55―60% of the triatomines were collected inside houses, and 30-35% of those were found in or near beds; thus, it is likely that they fed on humans. To our knowledge, this study is the first comprehensive multi-year analysis of triatomine distribution and abundance in the U.S., providing data that allow inferences about risks to human health.

Agronomy, agriculture, phytopathology, Agronomie, agriculture, phytopathologie, Entomology, Entomologie, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Ecologie animale, vegetale et microbienne, Animal, plant and microbial ecology, Ecologie animale et végétale, Animal and plant ecology, Autoécologie, Autoecology, Végétaux et champignons, Plants and fungi, Synécologie, Synecology, Ecosystèmes terrestres, Terrestrial ecosystems, Angiospermae, Arthropoda, Composé allélochimique, Allelochemicals, Aleloquímicos, Entomophage, Entomophagous, Entomófago, Gramineae, Heteroptera, Hymenoptera, Insecta, Invertebrata, Monocotyledones, Pentatomidae, Scelionidae, Spermatophyta, Attraction, Atracción, Chimiotactisme, Chemotaxis, Quimiotactismo, Composé volatil, Volatile compound, Compuesto volátil, Déprédateur, Pest, Plaga, Kairomone, Kairomona, Oryza sativa, Parasitoïde, Parasitoid, Parasitoide, Plante céréalière, Cereal crop, Planta cerealista, Relation animal végétal, Animal plant relation, Relación animal vegetal, Système tritrophique, Tritrophic system, Sistema tritrófico, Sécrétion défensive, Defensive secretion, Secreción defensiva, Trissolcus basalis, Platygastridae, Telenomus podisi, Tibraca limbativentris, kairomone, rice plants, semiochemical, and stink bug

The rice stem bug, Tibraca limbativentris Stal. (Hemiptera: Pentatomidae) is one of the most important pests of rice crops, especially irrigated crops. Plant defence strategies against these bugs may involve the emission of chemical compounds, which are released following herbivore attacks, directly or indirectly harming pest performance. The aim of this study was to evaluate the influence of constitutive and herbivory-induced volatiles from rice plants (Oryza sativa L.) on the behavioural responses of T. limbativentris adults and egg parasitoids Trissolcus basalis (Wollaston) and Telenomus podisi (Ashmead) (Hymenoptera, Platygastridae). Plant volatiles were collected from undamaged plants of the rice cultivar IRGA 424 and from plants that suffered herbivory by five males or five females of T. limbativentris. Air-entrainment extracts were analysed by GC―flame ionization detector and GC-MS, and insect responses evaluated in a 'Y' olfactometer. T. limbativentris feeding damaged on rice plants induced the release of 16 volatiles compounds in a higher amounts compared to undamaged plants The main compounds induced were (E)-2-hexenal, (E)-2-octen-1-ol, methyl salicylate and α-muurolene. Female bugs were significantly attracted to air-entrainment extracts containing volatiles from undamaged plants compared with air-entrainment extracts containing volatiles emitted from plants damaged by T. limbativentris, whereas males showed no preference. Telenomus podisi females were significantly attracted to volatiles from air-entrainment extracts of plants damaged by females, whereas T. basalis showed no preference. These results suggest that rice plants may be emitting defence compounds, which could be avoided by T. limbativentris females and also acted indirectly by attracting natural enemies.

Agronomy, agriculture, phytopathology, Agronomie, agriculture, phytopathologie, Entomology, Entomologie, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Phytopathologie. Zoologie agricole. Protection des cultures et des forets, Phytopathology. Animal pests. Plant and forest protection, Protozoaires. Invertébrés, Protozoa. Invertebrates, Lutte, Control, Lutte chimique, Chemical control, Angiospermae, Arthropoda, Gramineae, Invertebrata, Monocotyledones, Pesticide, Pesticides, Plaguicida, Plante céréalière, Cereal crop, Planta cerealista, Spermatophyta, Zone tropicale, Tropical zone, Zona tropical, Date de plantation, Planting date, Fecha de plantación, Déprédateur, Pest, Plaga, Fertilisation azotée, Nitrogen fertilization, Fertilización nitrogenada, Infestation, Infestación, Insecta, Insecticide, Insecticida, Irrigation, Irrigación, Lutte antidéprédateur, Pest management, Manejo de plagas, Lutte chimique, Chemical control, Lucha química, Oryza sativa, Prise décision, Decision making, Toma decision, Rendement, Yield, Rendimiento, Résistance insecte, Insect resistance, Resistencia insecto, Seuil intervention, Action threshold, Umbral tratamiento, Pest control, colonisation pattern, decision making, insecticides, irrigated rice, nitrogen fertilisation, plant tolerance, planting date, and yield loss

Action thresholds as decision tools for insecticide application were developed and tested against the major insect pests of rice at four sites in the Philippines over a 13-year period. Action threshold treatments were compared to the farmers' practice, prophylactic insecticide usage, and an untreated check. Yield loss data using the insecticide check method partitioned yield losses over three crop growth stages in the same test fields. Chronic pests that exceeded action thresholds in 79% of fields were whorl maggot Hydrellia philippina Ferino (Diptera: Ephydridae), defoliators Naranga senescens Moore and Rivula atimeta (Swinhoe) (Lepidoptera: Noctuidae), leaffolders Cnaphalocrocis medinalis (Guenée) and Marasmia patnalis Bradley (Lepidoptera: Pyralidae), and stemborers Scirpophaga incertulas (Walker) and S. innotata (Walker) (Lepidoptera: Pyralidae). Minor chronic pests reached threshold levels in only one site each: rice bug Leptocorisa oratorius (F.) (Koronadal), whitebacked planthopper Sogatella furcifera (Horvath) (Zaragoza) and green leafhopper Nephotettix virescens (Distant) (Guimba); brown planthopper Nilaparvata lugens (Stål) did not exceed a threshold in any field. Stemborers were the most important pest group in terms of yield loss. Despite the insecticide check method underestimating losses, a mean crop loss of 0.62 t/ha was measured which showed ample scope for corrective action. But loss was evenly distributed across crop growth stages (0.15 0.24 t/ha) reducing the impact of insecticides. Action threshold treatments overall outyielded the untreated check, more so in the two sites with highest pest density. The benefit of thresholds was to reduce insecticide usage, as a cost saving. However all the practices showed poor economic returns including the farmers' practice. Farmers' practice employed low insecticide dosages and timing was not consistent with pest damage, but yields were often similar to threshold treatments. Farmers appear to use insecticide more for risk aversion than for profit. The best threshold characters when evaluated against resulting pest density and yield loss criteria showed accuracies > 90% correct decisions. Future work is needed to improve the insecticide response rather than monitoring tools. Thresholds need to be incorporated into improved crop management, which was often found suboptimal by farmers, to take advantage of the high levels of tolerance in modern high tillering cultivars. Crop husbandry practices which improve yield potential such as selection of longer maturing varieties and nitrogen fertilizer may be a more effective pest management strategy than insecticides.

Agronomy, agriculture, phytopathology, Agronomie, agriculture, phytopathologie, Entomology, Entomologie, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Vecteurs d'importance medicale, nuisances, depredateurs des denrees et materiaux: surveillance des populations et lutte, Medically important nuisances and vectors, pests of stored products and materials: population survey and control, Vecteurs. Hôtes intermédaires, Vectors. Intermediate hosts, Arthropoda, Heteroptera, Infection, Infección, Insecta, Invertebrata, Parasitose, Parasitosis, Protozoose, Protozoal disease, Protozoosis, Reduviidae, Trypanosomiase, Trypanosomiasis, Tripanosomiasis, Fitness, Adecuación, Rhodnius prolixus, Surveillance population, Population survey, Vigilancia población, Trypanosomiase américaine, Chagas disease, Tripanosomiasis americana, Vecteur, Vector, Triatominae, biodemography, cost of reproduction, and tradeoff

Rhodnius prolixus Stal (Reduviidae: Rhodninii) is one of the most important vectors of Chagas disease. As a result of its medical importance, several life history studies have been carried out, but in general with a restricted demographical scope, without assessing the potential tradeoffs in the life history of this insect. In this study, individuals of R. prolixus were kept in two spatially different habitats and several fitness components were measured. The results show that life expectancy in adults is negatively correlated with gross fecundity, indicating a cost of reproduction. Life expectancy is shorter for males arid longer for individuals of the same sex in the more complex habitat, where the fitness is lower compared with that of the simpler habitat.

Agronomy, agriculture, phytopathology, Agronomie, agriculture, phytopathologie, Entomology, Entomologie, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Ecologie animale, vegetale et microbienne, Animal, plant and microbial ecology, Ecologie animale et végétale, Animal and plant ecology, Autoécologie, Autoecology, Végétaux et champignons, Plants and fungi, Phytopathologie. Zoologie agricole. Protection des cultures et des forets, Phytopathology. Animal pests. Plant and forest protection, Protozoaires. Invertébrés, Protozoa. Invertebrates, Signalements, symptômes, dégâts, importance économique, surveillance des populations, Records, symptoms, damages, economic importance, population surveys, Angiospermae, Arthropoda, Dicotyledones, Heteroptera, Insecta, Invertebrata, Leguminosae, Légumineuse grain, Grain legume, Leguminosa grano, Relation animal végétal, Animal plant relation, Relación animal vegetal, Spermatophyta, Coreidae, Dégât, Damage, Estrago, Déprédateur, Pest, Plaga, Gousse, Pod, Vaina, Histopathologie, Histopathology, Histopatología, Plante hôte, Host plant, Planta huesped, Tissu végétal, Plant tissue, Tejido vegetal, and Vigna unguiculata

Histological studies were conducted on cowpea pods fed upon by the coreoid pod-sucking bugs, Anoplocnemis curvipes (Fabricius), Clavigralla tomentosicollis Stal, C. shadabi Dolling, Riptortus dentipes (Fabricius) and Mirperus jaculus (Thunberg). Various degrees of tissue and cellular disruption were apparent, especially in the brachysclereids. They were manifested in terms of plasmolysis, cell enlargement and cell wall disintegration depending on the coreoid species involved. The feeding site and its periphery had all the cells of the brachysclereids plasmolysed, with the parenchyma having broken cell walls in the case of A. curvipes. Riptortus dentipes and M. jaculus showed similar patterns of feeding activity but less extensive levels of damage. The Clavigralla spp., however, caused cell enlargement in the brachysclereids, and broken cell walls in both the brachysclereids and the parenchyma. Damage symptoms were observed in cells far away from the feeding sites of the bugs, suggesting the possibility of sucrase activity which has been reported to cause osmotic pump feeding in the Coreidae.

Agronomy, agriculture, phytopathology, Agronomie, agriculture, phytopathologie, Entomology, Entomologie, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Phytopathologie. Zoologie agricole. Protection des cultures et des forets, Phytopathology. Animal pests. Plant and forest protection, Protozoaires. Invertébrés, Protozoa. Invertebrates, Signalements, symptômes, dégâts, importance économique, surveillance des populations, Records, symptoms, damages, economic importance, population surveys, Angiospermae, Arthropoda, Dicotyledones, Heteroptera, Insecta, Invertebrata, Leguminosae, Relation animal végétal, Animal plant relation, Relación animal vegetal, Spermatophyta, Age, Edad, Comparaison interspécifique, Interspecific comparison, Comparación interespecífica, Coreidae, Dégât, Damage, Estrago, Déprédateur, Pest, Plaga, Gousse, Pod, Vaina, Légumineuse grain, Grain legume, Leguminosa grano, Pentatomidae, Position, Posición, and Vigna unguiculata

Laboratory and screenhouse studies were carried out to assess the relationship between pod age and pod position of cowpea and damage by different pod bug species. The coreids Clavigralla tomentosicollis Stäl and Riptortus dentipes Fabricius caused significant damage to young pods of cultivated genotypes, in contrast to the coreid Anoplocnemis curvipes Fabricius and the pentatomid Aspavia armigera Fabricius which exhibited minor feeding activity. Percent seed damage declined with pod age, the critical stage for pod bug infestation being when pods were about eight days old. Clavigralla tomentosicollis and R. dentipes caused significantly higher damage to pods located within the leaf canopy, thus behaving differently from Anoplocnemis curvipes which showed a distinct preference for pods growing above the leaf canopy. The feeding activity of Aspavia armigera was not affected by the position of pods on the plant. Overall, the study suggests that cowpea genotypes with a short flowering period and pods held above the leaf canopy offer the most promise in the management of pod-sucking pests.

Agronomy, agriculture, phytopathology, Agronomie, agriculture, phytopathologie, Ecology, Ecologie, Entomology, Entomologie, Environment, Environnement, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Phytopathologie. Zoologie agricole. Protection des cultures et des forets, Phytopathology. Animal pests. Plant and forest protection, Protozoaires. Invertébrés, Protozoa. Invertebrates, Lutte, Control, Lutte biologique, Biological control, Angiospermae, Arthropoda, Dicotyledones, Entomophage, Entomophagous, Entomófago, Heteroptera, Hymenoptera, Insecta, Invertebrata, Leguminosae, Relation hôte parasite, Host parasite relation, Relación huesped parásito, Spermatophyta, Animal auxiliaire, Beneficial animal, Animal benéfico, Coreidae, Densité population, Population density, Densidad población, Déprédateur, Pest, Plaga, Efficacité parasitaire, Parasitic efficiency, Eficacia parasitaria, Hôte, Host, Huesped, Lutte biologique, Biological control, Lucha biológica, Légumineuse grain, Grain legume, Leguminosa grano, Oophage, Oophagous, Oófago, Parasitoïde, Parasitoid, Parasitoide, Scelionidae, Taux parasitisme, Parasitism rate, Tasa parasitismo, Variation saisonnière, Seasonal variation, Variación estacional, Vigna unguiculata, Clavigralla tomentosicollis, Gryon fulviventris, and Nigeria du Nord

Field surveys were conducted on cowpea and pigeon pea in 1995 and 1996 to assess the effect of indigenous egg parasitoids on populations of Clavigralla tomentosicollis Stål in northern Nigeria. From the egg masses of C. tomentosicollis, three species of Hymenoptera belonging to three families, namel Anastatus sp. (Eupelmidae), Ooencyrtus utetheisae (Risbec) (Encyrtidae), and Gryon fulviventris (Crawford) (Scelionidae), were recorded. Among them, G. fulviventris was found to be the most abundant parasitoid. Of a total of 3,502 egg masses collected on cowpea from four geographical locations, 2,587 (73.9%) were found to contain at least one egg parasitized by G fulviventris. From 56,072 eggs discovered, it parasitized 38,935 (69.4%). Overall, 74,724 eggs were collected from the four different locations and of these 52% were parasitized by G. fulviventris. However, parasitism rates varied with time and location. At one of the study sites (Minjibir, Kano) where weekly samples were collected throughout the growing season, the discovery efficiency, exploitation efficiency, and overall percentage parasitism increased significantly from July to November. Also, the proportion of eggs parasitized was found to be inversely related to the size of the egg mass. These findings are discussed in relation to the potential contribution of biological control in the integrated pest management of this economically important pest.

Agronomy, agriculture, phytopathology, Agronomie, agriculture, phytopathologie, Entomology, Entomologie, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Phytopathologie. Zoologie agricole. Protection des cultures et des forets, Phytopathology. Animal pests. Plant and forest protection, Protozoaires. Invertébrés, Protozoa. Invertebrates, Signalements, symptômes, dégâts, importance économique, surveillance des populations, Records, symptoms, damages, economic importance, population surveys, Angiospermae, Arthropoda, Dicotyledones, Heteroptera, Insecta, Invertebrata, Solanaceae, Spermatophyta, Densité population, Population density, Densidad población, Durée, Duration, Duración, Dégât, Damage, Estrago, Déprédateur, Pest, Plaga, Fruit, Fruto, Infestation, Infestación, Lycopersicon esculentum, Maturité, Maturity, Madurez, Pentatomidae, Plante légumière, Vegetable crop, Planta leguminosa, Chlorochroa uhleri, and Euschistus conspersus

Adult stink bugs were introduced onto caged, bush-type tomatoes to establish the amount of fruit damage resulting from different durations of infestation (up to 20 d), densities (1, 3, 5, and 10 bugs per 2 m of row), species (Euschistus conspersus Uhler and Chlorochroa uhleri (stal)) and reduced fruit abundance (75, 50, and 0% reduction). Factors that significantly influenced the percentage of tomato fruit damaged were stink bug density and reduced fruit density at constant stink bug densities. Stink bug density affected the number of damaged areas per fruit in 1 of the 2 years of the study. Stink bug species and the number of days of stink bug infestation did not affect the percentage of damaged fruit or the number of damaged areas per fruit. Implications for stink bug management in tomatoes grown in California are discussed.

Agronomy, agriculture, phytopathology, Agronomie, agriculture, phytopathologie, Entomology, Entomologie, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Phytopathologie. Zoologie agricole. Protection des cultures et des forets, Phytopathology. Animal pests. Plant and forest protection, Protozoaires. Invertébrés, Protozoa. Invertebrates, Lutte, Control, Généralités, Generalities, Arthropoda, Composé sémiochimique, Semiochemicals, Heteroptera, Insecta, Invertebrata, Pentatomidae, Phéromone agrégation, Aggregation pheromone, Feromona agregación, aggregation pheromone, methyl (2E,6E)-farnesoate, methyl (E)-5-2,6,10-trimethyl-5,9-undecadienoate, methyl (E)-6-2,3-dihydrofarnesoate, and methyl geranate

In field trials, adult Chlorochroa uhleri (Stål) (Heteroptera: Pentatomidae) of both sexes were caught in significant numbers in cylindrical screen traps baited with gray rubber septum lures loaded with the main component of the male-produced pheromone, methyl (E)-6-2,3-dihydrofarnesoate. Addition of the two possible minor components of the pheromone, methyl (E)-5-2,6,10-trimethyl-5,9-undecadienoate and methyl (2E,6E) -farnesoate, did not affect attraction. Combining the pheromone with different concentrations of volatiles mimicking the odors of a known host plant, alfalfa (Medicago sativa L.), had no significant effect on attraction of adult bugs, whereas combining the pheromone with the pheromones of two sympatric stink bug species, Chlorochroa sayi (Stål) and Euschistus conspersus Uhler, decreased trap captures, suggesting interference between the pheromones. Small numbers of Chlorochroa ligata (Say) adults also were attracted, but numbers caught were too low to allow statistical comparisons between lure blends. In field trials with C. sayi, all three of the male-specific pheromone compounds [methyl geranate, methyl citronellate, and methyl (E) -6-2,3-dihydrofarnesoate] were required for optimal attraction. As with C. uhleri, adults of both sexes were attracted to pheromone lures in approximately equal numbers. Because of the decreased volatility (=release rate) of methyl (E)-6-2,3-dihydrofarnesoate in comparison with the other two, lower molecular weight pheromone components, lures needed to be loaded with a disproportionately high amount of methyl (E)-6-2,3-dihydrofarnesoate to obtain the best trap catch. There was no indication that the pheromone components of C. uhleri or E. conspersus interfered with the attractiveness of the C. sayi pheromone in lures containing a blend of all three pheromones.

Entomology, Entomologie, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Invertebres, Invertebrates, Insecta, Systématique. Répartition géographique, Systematics. Geographical distribution, Arthropoda, Etude expérimentale, Experimental study, Estudio experimental, Insecta, Invertebrata, Coreidae, Cycle évolutif, Life history, Ciclo evolutivo, Description, Descripción, Elevage, Rearing, Cría, Etude en laboratoire, Laboratory study, Estudio en laboratorio, Heteroptera, Laboratoire, Laboratory, Laboratorio, Narnia femorata, description, and life history

Narnia femorata Stål (Hemiptera: Heteroptera: Coreidae) is a leaffooted bug commonly found on Opuntia and Ferocactus cacti (Cactaceae) in southern New Mexico. Although general information has been published on the biology of this species, detailed studies are limited, particularly in America north of Mexico. Therefore, we conducted a study of this bug's life history in southern New Mexico from August 2010 to May 2012, reared the bug in the laboratory, and described the immature stages. Six prickly pear cactus plants, Opuntia phaeacantha Engelmann, and four barrel cactus plants, Ferocactus wislizeni (Engelmann) Britton & Rose, were examined weekly to record numbers of the various life stages, adult sex ratios, and behavioral activities. Adults of this apparently bivoltine species overwintered in plant debris at the bases of their host plants. They emerged in late February to deposit eggs in rows along the underside of cactus spines. Nymphs were found from late February through late December. Nymphs of the first generation were most abundant April through June on and around developing flowers of O. phaeacantha. Those of the second generation were most abundant during August and September on maturing fruit of O. phaeacantha and developing flowers and maturing fruit of F. wislizeni. The bug also was reared from egg to adult under controlled laboratory conditions on fruit and pads of O. phaeacantha at 25 ± 0.01°C under a photoperiod of 14:10 (L:D) h. The incubation period averaged 12.70 d. The five stadia averaged 3.84, 11.00, 12.12, 17.06, and 22.94 d, respectively. Instars can be distinguished readily by differences in several morphological features in addition to body size and coloration.

Agronomy, agriculture, phytopathology, Agronomie, agriculture, phytopathologie, Entomology, Entomologie, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Phytopathologie. Zoologie agricole. Protection des cultures et des forets, Phytopathology. Animal pests. Plant and forest protection, Protozoaires. Invertébrés, Protozoa. Invertebrates, Lutte, Control, Généralités, Generalities, Vecteurs d'importance medicale, nuisances, depredateurs des denrees et materiaux: surveillance des populations et lutte, Medically important nuisances and vectors, pests of stored products and materials: population survey and control, Vecteurs. Hôtes intermédaires, Vectors. Intermediate hosts, Arthropoda, Bactérie, Bacteria, Cicadomorpha, Homoptera, Insecta, Invertebrata, Mollicutes, Mycoplasmatales, Spiroplasmataceae, Cicadellidae, Dalbulus maidis, Etude expérimentale, Experimental study, Estudio experimental, Maïs, Corn, Maiz, Spiroplasma kunkelii, Vecteur, Vector, corn leafhopper, corn stunt, and spiroplasmas

Corn stunt caused by the mollicute Spiroplasma kunkelii (Whitcomb) is potentially one of the most severe diseases affecting the corn (Zea mays L.) crop in the Americas, and the leafhopper Dalbulus maidis (DeLong & Wolcott) is considered its most important vector. However, other insects seen quite frequently in corn crops might well be its vectors in Argentina. To identify any leafhoppers species other than D. maidis that can transmit S. kunkelii, transmission assays were conducted, using individuals of Exitianus obscurinervis (Stål) collected in field and reared under controlled conditions. S. kunkelii was transmitted to corn plants by E. obscurinervis. The pathogen was transmitted to seven of the 11 plants, which showed characteristic corn stunt symptoms, and the presence of the pathogen was confirmed by DAS-ELISA. The presence of S. kunkelii in the E. obscurinervis individuals used in transmission experiments was confirmed by polymerase chain reaction and electron microscopy. The current study shows the existence of a new experimental vector of S. kunkelii, the leafhopper E. obscurineruis, which acquired spiroplasmas from infected plants and inoculated it to healthy plants.

Agronomy, agriculture, phytopathology, Agronomie, agriculture, phytopathologie, Entomology, Entomologie, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Phytopathologie. Zoologie agricole. Protection des cultures et des forets, Phytopathology. Animal pests. Plant and forest protection, Protozoaires. Invertébrés, Protozoa. Invertebrates, Lutte, Control, Lutte intégrée, Integrated pest control, Angiospermae, Arthropoda, Bruchidae, Coleoptera, Dicotyledones, Heteroptera, Insecta, Invertebrata, Leguminosae, Reduviidae, Spermatophyta, Callosobruchus maculatus, Canavalia ensiformis, Croissance, Growth, Crecimiento, Déprédateur, Pest, Plaga, Emergence, Emergencia, Insecticide, Insecticida, Larve, Larva, Légumineuse grain, Grain legume, Leguminosa grano, Mortalité, Mortality, Mortalidad, Mue, Molt, Muda, Origine végétale, Plant origin, Origen vegetal, Rhodnius prolixus, Toxicité, Toxicity, Toxicidad, Toxine, Toxin, and Toxina

Canatoxin is a toxic protein isolated from the jackbean, Cananvalia ensiformis. The toxin injected intraperitoneally is lethal for mice and rats; however, it is inactive if given orally. In this study, Manduca sexta (L.) (Lepidoptera), Schistocerca americana (Drury) (Orthoptera), Drosophila melanogaster (L.) (Diptera), Aedes aegypti (L.) (Diptera), Rhodnius prolixus (Stal) (Hemiptera), and Callosobruchus maculatus (F.) (Coleoptera) were fed on can-atoxin-containing diets. No effects were seen in M. sexta, S. americana, D. melanogaster, or A. aegypti. No traces of canatoxin were found in their feces, suggesting that the protein was digested completely by these insects, which characteristically have a trypsin-based digestion. In contrast, canatoxin was lethal for insects displaying cathepsin-based digestion. Thus, for C. maculatus, a diet containing 0.25% wt:wt canatoxin caused complete inhibition of larval growth. When R. prolixus were fed on canatoxin, 2 effects were seen: impairment of water excretion and increased lethality 48-96 h after feeding. The lethal effect of canatoxin in R. prolixus was blocked partially or completely when the digestion of the toxin by R. prolixus midgut enzymes was impaired. The data showed that canatoxin is highly toxic when ingested by some species of insects but not affecting others, probably in correlation with the characteristics of the digestive process of the insect.

Agronomy, agriculture, phytopathology, Agronomie, agriculture, phytopathologie, Ecology, Ecologie, Entomology, Entomologie, Environment, Environnement, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Phytopathologie. Zoologie agricole. Protection des cultures et des forets, Phytopathology. Animal pests. Plant and forest protection, Protozoaires. Invertébrés, Protozoa. Invertebrates, Signalements, symptômes, dégâts, importance économique, surveillance des populations, Records, symptoms, damages, economic importance, population surveys, Angiospermae, Arthropoda, Dicotyledones, Facteur milieu, Environmental factor, Factor medio, Heteroptera, Insecta, Invertebrata, Leguminosae, Spermatophyta, Coreidae, Défoliation, Defoliation, Defoliación, Dégât, Damage, Estrago, Déprédateur, Pest, Plaga, Feuille végétal, Plant leaf, Hoja vegetal, Gousse, Pod, Vaina, Infestation, Infestación, Structure, Estructura, Température, Temperature, Temperatura, Vigna unguiculata, Anoplocnemis curvipes, Clavigralla tomentosicollis, canopy temperature, defoliation, and pod position

Potted cowpea, Vigna unguiculata (L.) Walp., plants were used to determine the effects of defoliation and pod position relative to the leaf canopy on infestation and damage by the coreid pod-bugs Clavigralla tomentosicollis Stål and Anoplocnemis curvipes (F.). Temperature measurements were taken within and outside the canopy to determine whether there was a correlation to seed damage. Seed damage decreased significantly with increasing defoliation in plants infested with C. tomentosicollis; an inverse trend was observed with A. curvipes. Temperatures within the canopy increased as the number of leaves decreased. As observed in the defoliation experiment, C. tomentosicollis and A. curvipes reacted differently in a free-choice situation between pods located outside or within the canopy. Significantly higher numbers of C. tomentosicollis concealed themselves within the canopy, where they caused more severe damage to seeds, in comparison with numbers and damage outside the canopy. These trends were reversed for A. curvipes. There was a significant negative correlation between percentage of seed damage and temperature with C. tomentosicollis, and a significant positive correlation with A. curvipes, both in defoliated plants and those with pods distributed outside and within the canopy. Overall, plants with less dense canopy, and long peduncles holding pods outside the canopy showed some resistance to C. tomentosicollis, which is the most damaging pod bug on cowpea. Because such cowpea plants harbor fewer C. tomentosicollis, they are likely to suffer less overall damage from infestation by the complex of pod bugs that occur concurrently in cowpea fields.

Agronomy, agriculture, phytopathology, Agronomie, agriculture, phytopathologie, Entomology, Entomologie, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Phytopathologie. Zoologie agricole. Protection des cultures et des forets, Phytopathology. Animal pests. Plant and forest protection, Protozoaires. Invertébrés, Protozoa. Invertebrates, Angiospermae, Arthropoda, Dicotyledones, Heteroptera, Insecta, Invertebrata, Plante légumière, Vegetable crop, Hortalizas (plantas), Solanaceae, Spermatophyta, Animal auxiliaire, Beneficial animal, Animal benéfico, Déprédateur, Pest, Plaga, Habitat, Lutte biologique, Biological control, Lucha biológica, Lycopersicon esculentum, Pentatomidae, Plante sauvage, Wild plant, Planta salvaje, Tomate, Tomato, Hemiptera, Thyanta, Euschistus conspersus, Lobularia maritima, Thyanta pallidovirens, conservation biological control, consperse stink bug, pest habitat, and red shouldered stink bug

We investigated the effects of weed hosts on stink bug density and damage (Euschistus conspersus Uhler and Thyanta pallidovirens Stal), and a nectar bearing plant on natural enemies of stink bugs in the Sacramento Valley of California. Stink bug density and fruit damage were evaluated in processing tomatoes adjacent to weedy and cultivated borders. The density of E. conspersus was significantly greater in tomatoes adjacent to weedy borders in July but not during August/September. Thyanta pallid-ovirens was less abundant overall (19%), but was found in significantly greater densities adjacent to cultivated borders in July but not in August/September. Mean percent fruit damage by stink bugs was greater adjacent to the weedy border than the cultivated border, but this difference was not significant. Stink bug egg parasitism and generalist predator density were evaluated in fresh market tomatoes adjacent to a sweet alyssum (Lobularia maritima L.) border and an unplanted control border at three sites. Egg parasitism was significantly greater in the alyssum treatment for the 9―12 September sampling period. Jalysus wickhami VanDuzee (Hemiptera: Berytidae) density was significantly greater in the alyssum treatment in mid-June. No other significant differences in predator populations were detected. Results of these two studies show that habitat manipulations have the potential to reduce densities of E. conspersus in tomato, the first step in developing a farmscape management plan for stink bug control.