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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, 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, 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.

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, Spermatophyta, Coreidae, Déprédateur, Pest, Plaga, Plante légumière, Vegetable crop, Planta leguminosa, Relation animal végétal, Animal plant relation, Relación animal vegetal, Rendement, Yield, Rendimiento, Seuil dégât économique, Economic injury level, Umbral daño económico, Seuil intervention, Treatment threshold, Umbral tratamiento, Surveillance population, Population survey, Vigilancia población, Vigna unguiculata, and Clavigralla tomenta sicollis

PLANT chemical defenses, VIGNA, and COREIDAE

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. [ABSTRACT FROM AUTHOR]

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.

HEMIPTERA, COREIDAE, INSECT development, OPUNTIA, and FEROCACTUS

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 phaeacantlut 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. [ABSTRACT FROM AUTHOR]

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.