Prospection, Enquête et Collectes des Accessions de Poivron (Capsicum annuum L.) Cultivés dans la Région de Diffa, Niger

Au Niger, particulièrement dans la région de Diffa, le poivron est la spéculation la plus cultivée et la plus commercialisée, représentant ainsi le poumon économique de la région. Pour accroitre la production et prévenir toute érosion génétique, des connaissances sur la diversité génétique et les pratiques paysannes de la gestion du poivron sont nécessaires. C’est ainsi qu’une prospection suivie de collecte de graines a été effectuées dans toute la région de Diffa. La méthode d’obtention des données et de collecte des accessions à consister en des entretiens directs avec les paysans et les commerçants du poivron aléatoirement choisis dans les villages ou sites d’exploitations.  Le géo référencement de tous les sites/villages visités a été effectué et une carte est établie. Dix-neuf (19) sites (ou villages) ont été prospectés à travers la région et cinquante un (51) accessions collectées. L’étude révèle que la culture du poivron est plus pratiquée par la classe d’âge moins avancée (18-45 ans) avec une fréquence qui varie de 50% (Diffa) à 77% (Nguigmi). Cette culture est pratiquée majoritairement par les hommes dans toutes les zones prospectées. Les résultats montrent également que les « kanuri » sont majoritairement producteurs de cette spéculation avec une fréquence qui varie de 84% (Nguigmi) à 100% (Bosso et Diffa). La culture est en régression dans certaines localités (Département de Diffa, de Bosso et de Maine Soroa) compte tenu des certaines contraintes biotiques (ravageurs) et abiotiques (inondation, insécurité). A la fin, du matériel pour les programmes d’amélioration du poivron est disponible au Niger.   In Niger, particularly in the Diffa region, bell pepper is the most cultivated and marketed  crop, thus representing the economic lung of the region. To increase production and prevent genetic erosion, knowledge of genetic diversity and farmers’ practices  is needed. Thus, a survey  followed by seed collection was  conducted throughout the Diffa region. The method of obtaining data and collecting accessions consisted of direct interviews with farmers and bell pepper traders randomly selected in the villages or farmers sites. Geo-referencing of all the sites/villages visited has been carried out and a map  was established. Nineteen (19) sites (or villages) were surveyed across the region and fifty-one (51) accessions collected. The study revealed that bell pepper cultivation is more common among  the younger age group (18-45 years) with a frequency that varies from 50% (Diffa) to 77% (Nguigmi). This crop is grown mainly by men in all the zones surveyed . The results also showed that the "kanuri" are the main producers of this crop with a frequency that varies from 84% (Nguigmi) to 100% (Bosso and Diffa). Production is declining in some localities (Departments of Diffa, Bosso and Maine Soroa) due to certain biotic (pests) and abiotic (flooding, insecurity) constraints.  Finally, materials for bell pepper improvement programs are available in Niger

Prospection, Enquête et Collectes des Accessions de Poivron (Capsicum Annuum L.) Cultivés dans la Région de Diffa, Niger

Le poivron est une plante polyvalente utilisé soit comme épice, soit comme légume-fruit dans la plupart des mets. Sa poudre communément appelé paprika est un condiment largement consommé dans le monde. Au Niger, particulièrement dans la région de Diffa, le poivron est la spéculation la plus cultivée et la plus commercialisée, représentant ainsi le poumon économique de la région. Une prospection suivie d’une enquête et d’une collecte des accessions de poivron a été effectuée dans cinq (5) départements de production de la région de Diffa. Dix-neuf (19) sites/villages ont été prospectés à travers la région. Tous les sites/villages visités ont été géo référencées et une carte a été établie. Au total cinquante un (51) accessions ont été collectées. Il ressort de l’entretien que la culture du poivron est plus pratiquée par la classe d’âge moins avancée avec une fréquence qui varie de 77% (Nguigmi) à 50% (Diffa). Cette culture est pratiquée majoritairement par les hommes dans toutes les zones prospectées. Les résultats montrent également que les kanuri sont majoritairement producteurs de cette spéculation avec une fréquence qui varie de 100% (Bosso et Diffa) à 84% (Nguigmi). La culture est en régression dans certaines localité compte tenu des certaines contraintes biotiques (ravageurs) et abiotiques (inondation, insécurité). Apres les récoltes les fruits sont commercialisés dans les marchés locaux ou régionaux, majoritairement dans le département de Diffa (87%) et en moindre importance dans le département de Bosso (32%). Le prix d’un sac de poivron sec de 17 kg varie de 11 000 à 44 000 FCFA selon les périodes et la disponibilité en quantité et en qualité des fruits.   The pepper is a versatile plant used either as a spice or as a fruit vegetable in most dishes. Its powder commonly called paprika is a widely consumed condiment in the world. In Niger, particularly in the Diffa region, the pepper is the most cultivated and most marketed speculation, thus representing the economic lung of the region. A survey followed by a survey and a collection of pepper accessions was carried out in five (5) production departments of the Diffa region. Nineteen (19) sites/villages were surveyed across the region. All the sites/villages visited have been geo-referenced and a map has been drawn up. A total of fifty one (51) accessions were collected. It appears from the interview that pepper cultivation is more practiced by the younger age group with a frequency that varies from 77% (N’guigmi) to 50% (Diffa). This culture is practiced mainly by men in all surveyed areas. The results also show that the kanuri are mainly producers of this speculation with a frequency that varies from 100% (Bosso and Diffa) to 84% (N’guigmi). Cultivation is declining in some localities due to certain biotic (pests) and abiotic (flooding, insecurity) constraints. After the harvest, the fruits are marketed in local or regional markets, mainly in the department of Diffa (87%) and to a lesser extent in the department of Bosso (32%). The price of a 17 kg bag of dry peppers varies from 11,000 to 44,000 FCFA depending on the period and the availability in quantity and quality of the fruits

Prospection, Enquête et Collectes des Accessions de Poivron (Capsicum Annuum L.) Cultivés dans la Région de Diffa, Niger

Le poivron est une plante polyvalente utilisé soit comme épice, soit comme légume-fruit dans la plupart des mets. Sa poudre communément appelé paprika est un condiment largement consommé dans le monde. Au Niger, particulièrement dans la région de Diffa, le poivron est la spéculation la plus cultivée et la plus commercialisée, représentant ainsi le poumon économique de la région. Une prospection suivie d’une enquête et d’une collecte des accessions de poivron a été effectuée dans cinq (5) départements de production de la région de Diffa. Dix-neuf (19) sites/villages ont été prospectés à travers la région. Tous les sites/villages visités ont été géo référencées et une carte a été établie. Au total cinquante un (51) accessions ont été collectées. Il ressort de l’entretien que la culture du poivron est plus pratiquée par la classe d’âge moins avancée avec une fréquence qui varie de 77% (Nguigmi) à 50% (Diffa). Cette culture est pratiquée majoritairement par les hommes dans toutes les zones prospectées. Les résultats montrent également que les kanuri sont majoritairement producteurs de cette spéculation avec une fréquence qui varie de 100% (Bosso et Diffa) à 84% (Nguigmi). La culture est en régression dans certaines localité compte tenu des certaines contraintes biotiques (ravageurs) et abiotiques (inondation, insécurité). Apres les récoltes les fruits sont commercialisés dans les marchés locaux ou régionaux, majoritairement dans le département de Diffa (87%) et en moindre importance dans le département de Bosso (32%). Le prix d’un sac de poivron sec de 17 kg varie de 11 000 à 44 000 FCFA selon les périodes et la disponibilité en quantité et en qualité des fruits.   The pepper is a versatile plant used either as a spice or as a fruit vegetable in most dishes. Its powder commonly called paprika is a widely consumed condiment in the world. In Niger, particularly in the Diffa region, the pepper is the most cultivated and most marketed speculation, thus representing the economic lung of the region. A survey followed by a survey and a collection of pepper accessions was carried out in five (5) production departments of the Diffa region. Nineteen (19) sites/villages were surveyed across the region. All the sites/villages visited have been geo-referenced and a map has been drawn up. A total of fifty one (51) accessions were collected. It appears from the interview that pepper cultivation is more practiced by the younger age group with a frequency that varies from 77% (N’guigmi) to 50% (Diffa). This culture is practiced mainly by men in all surveyed areas. The results also show that the kanuri are mainly producers of this speculation with a frequency that varies from 100% (Bosso and Diffa) to 84% (N’guigmi). Cultivation is declining in some localities due to certain biotic (pests) and abiotic (flooding, insecurity) constraints. After the harvest, the fruits are marketed in local or regional markets, mainly in the department of Diffa (87%) and to a lesser extent in the department of Bosso (32%). The price of a 17 kg bag of dry peppers varies from 11,000 to 44,000 FCFA depending on the period and the availability in quantity and quality of the fruits

Succession des communautés végétales des jachères protégées en zone sahélienne: cas de Banizoumbou (Niger)

Objectif: L’importance de la perturbation (en durée ou en intensité) semble décisive pour déterminer l'état de la végétation et la dynamique successionnelle. L’objectif de la présente étude est d'examiner les variations des paramètres écologiques des champs et des jachères protégées de Banizoumbou.Méthodologie et résultats: Les relevés phyto-sociologiques ont été réalisés selon la méthode sigmatiste de Braun-Blanquet (1932). L’échantillonnage a été effectué sur la base de types des systèmes, ainsi les jachères et les champs ont fait l’objet d’inventaire suivant 6 transect, des placettes de 1000 m2 équidistantes de 500 m ont été placé. Ainsi au total 33 relevés ont été effectués dont 18 dans la jachère et 15 relevés dans le champ. Il ressort de l’étude que la diversité dépend de stade successionnel même à l’intérieur d’un même type d’occupation. L’analyse des indices montre qu’en plus des jachères, les champs sont aussi d’importantes sources de biodiversité. Ainsi l’indice de diversité de Shannon évolue en fonction de l’âge de jachère et de champ, mais toute fois il évolue beaucoup plus rapidement au niveau de jachère que le champ. La densité moyenne de la zone d’étude est de 260 individus par hectare dont Guiera senegalensis représente plus de 70%. La hauteur moyenne, le diamètre moyen, la densité moyenne et le recouvrement moyen les plus élevés sont observés au niveau des jachères.Conclusion et application of résultats: la présente étude a montré que la variation de la diversité végétale est une fonction de l’âge aussi bien au niveau des champs que les jachères. Ainsi la diversité évolue plus rapidement au niveau des jachères.Mots clés: Succession des communautés végétales, jachères protégées de BanizoumbouEnglish AbstractObjective: The importance of disturbance (duration or intensity) seems decisive in determining the state of vegetation and successional dynamics. The purpose of this study is to study and examine variations in the floristic richness, diversity and production of protected fallow land in Banizoumbou.Methodology and Results: The phyto-sociological surveys were carried out according to the sigmatist method of Braun-Blanquet (1932). Sampling was carried out on the basis of land use types, so fallows and fields were  inventoried following 6 transect, 1000 square meter equidistant plots of 500 m were set. A total of 33 surveys were carried out, including 18 in the fallows and 15 in the fields. Our findings show that diversity depends on the successional stage even within the same type of land use. Analysis of the indices shows that in addition to fallow land, fields are also important sources of biodiversity. Thus, Shannon's diversity index increases according to the fallow and field age, but this increase is much higher in the fallows in than the fields. The results reveal also that average density of the study area is 260 individuals per hectare, of which Guiera senegalensis represents more than 70%. The mean height, mean diameter, average density and highest average cover were observed at fallow land.Conclusion and Application of results: The present study showed that variation in plant diversity is a function of age at both field and fallow land. Thus diversity evolves more rapidly at fallow land.Keywords: Succession of plant communities, protected fallow land of Banizoumbo

Étude floristique des formations naturelles à Vachellia tortilis subsp. raddiana en zone sahélienne du Niger

This study was conducted in the departments of Maine-Sorao and Goudoumaria located in the region of Diffa, in the extreme south-east of Niger. The objective of the study is to analyse the ecological and floristic indicators of natural formations of Acacia tortilis subsp. raddiana (Savi) Brenan. Phytosociological data were collected using the sigmatist method of Braun-Blanquet and the quadrat point method of Daget and Poissonet. A total of 80 plots were delimited. The data collected are related to the coverage of plant species and environmental variables. The spectra of biological and phytogeographic types were calculated. Hierarchical Ascending Classification (AHC), Canonical Defined Analysis (CDA) and Canonical Correspondence Analysis (CCA) were used to determine plant groupings and their ecological and floristic characteristics. The results revealed a total species richness of 61 plant species divided into 25 families and 51 genera. The most represented families are Poaceae (19.7%) and Leguminosae-Mimosoideae (11.5%). The Therophytes are the most represented biological type (59.0%). Paleotropical species is the dominant phytogeographic type (37.7%). The hierarchical ascending classification (CHA) and the Canonical Correspondence Analysis (CCA) made it possible to discriminate three (3) plant groups with A. tortilis. These are the group with A. tortilis and Echinochloa colona (G1) observed in the lowlands; the group with A. tortilis and Alysicarpus ovalifolius (G2) on the dune slopes and the group with A. tortilis and Chloris barbata (G3) on the dune flats. Analysis of diameter class structures shows a dominance of small-diameter individuals in all groups with shape c parameters of the theoretical Weibull distribution greater than 1, suggesting that A. tortilis stands are characterized by a lack of regeneration, the causes of which include fruit picking by shepherds and overgrazing. These results reveal the state of degradation and disturbance of steppe vegetation in the study areas. This study constitutes a reference state that can serve as a basis for sustainable management of the ecosystems of these areas, whose main uses are essentially pastoral.  Keywords: Acacia tortilis, Biological types, Phytogeographic types, Floristic diversity, NigerLa présente étude a été conduite dans les départements de Maine-Sorao et Goudoumaria situés dans la région de Diffa, à l’extrême sud-est du Niger. L’objectif de l’étude est d’analyser les indicateurs écologique et floristique des formations naturelles à Acacia tortilis subsp. raddiana (Savi) Brenan. Les données phytosociologiques ont été collectées à l’aide de la méthode sigmatiste de Braun-Blanquet et celle de point quadrat de Daget et Poissonet. Au total, 80 placettes ont été délimitées. Les données collectées sont relatives au recouvrement des espèces végétales et les variables environnementales. Les spectres des types biologiques et phytogéographiques ont été calculés. La classification hiérarchique ascendante (CHA), l’Analyse Canonique Detendancée (DCA) et l’Analyse Canonique des Correspondances (CCA) ont été utilisées pour déterminer les groupements végétaux et leurs caractéristiques écologique et floristique. Les résultats ont révélé une richesse spécifique totale de 61 espèces végétales reparties en 25 familles et 51 genres. Les familles les plus représentées sont les Poaceae (19,7%) et les Leguminosae-Mimosoideae (11,5 %). Les Thérophytes constituent le type biologique le plus représenté (59,0%). Les espèces Paléotropicales est le type phytogéographique dominant (37,7%). La classification hiérarchique ascendante (CHA) et l’Analyse Canonique des Correspondances (CCA) ont permis de discriminer trois (3) groupements végétaux à A. tortilis. Il s’agit du groupement à Acacia tortilis et Echinochloa colona (G1) observé dans les bas-fonds ; du groupement à Acacia tortilis et Alysicarpus ovalifolius (G2) sur les versants dunaires et du groupement à Acacia tortilis et Chloris barbata (G3) sur les replats dunaires. L’analyse des structures en classe de diamètres montre une dominance des individus de faible diamètre au niveau de tous les groupements avec des paramètres de forme c de la distribution théorique de Weibull supérieur à 1. Cela suggère que les peuplements de A. tortilis sont caractérisés par un manque de régénération dont les causes sont entre autres le ramassage des fruits par les bergers et le surpâturage. Ces résultats révèlent l’état de dégradation et de perturbation de végétation steppique des zones d’étude. Cette étude constitue un état de référence pouvant servir de base pour une gestion durable des écosystèmes de ces zones dont les principales utilisations sont essentiellement pastorales.  Mots clés: Acacia tortilis, Types biologiques, Types phytogéographiques, Diversité floristique, Nige

Influence De La Géomorphologie Sur La Distribution Spatiale Des Peuplements De Boscia Senegalensis (Pers.) Lam. Ex Poir. Dans La Commune Rurale De Simiri (Ouest Niger)

B. senegalensis is a species with broad geographic distribution in the Sahel, especially in Niger, thanks to its special anatomical structures to withstand drought, high temperatures and poor soils. It presents and a heterogeneous distribution in the following areas topographic levels characteristic of the western Niger. This paper aimed to assess the distribution of B. senegalensis and its relationship with woody species through the description of the spatial structure of the point process following toposequences by Ripley's method stands. The study highlighted the gregarious distribution of B. senegalensis and the close relationship between B. senegalensis and other species. Indeed, the species is in competition with other species on the plateau where water resources are scarce. But B. senegalensis tolerate these species on the slopes and in the shallows where water resources are relatively large

Tuberculosis in Vaccinated versus Unvaccinated Children with BCG Vaccine in Niamey: Epidemiological, Diagnostic and Outcome Aspects

Introduction: Tuberculosis remains a public health problem worldwide. The BCG vaccination is one of response means. The objective of this work was to study impact of BCG vaccination on morbidity and mortality related to childhood tuberculosis in Niamey. Patients and methods: It was a multicenter prospective and comparative study from January to September 2017 in two-referral hospital centers of Niamey and the National Anti-Tuberculosis Center. The study population consisted exhaustively of children aged 0 to 15 years old suffering from tuberculosis. Epidemiological, diagnostic and evolving aspects in vaccinated and unvaccinated children were studied. Statistical tests used were Pearson's Chi² and Fisher's exact test (p <0.05). Results: Ninety-one children were studied. The BCG vaccination rate was 60.4%. The mean age of children was 6 years 11 months [3 months-15 years]. Children under 2 years of age were less affected (11%) in vaccinated children than in unvaccinated children (3.2%). No association was found between duration of tuberculosis signs (p = 0.37), expression of tuberculin skin test (p = 0.43), and the children's BCG vaccination status. On the other hand, there was a significant link between vaccination status and the results of microscopic examination of sputum or gastric fluid (p = 0.02), occurrence of complications (p = 0.014) and death risk (p = 0.003). Conclusion: This study shows that children’s BCG vaccination status interferes with some aspects of tuberculosis. Therefore, fighting against tuberculosis must be intensified, through combination of many strategies including vaccination

Tuberculosis in Vaccinated versus Unvaccinated Children with BCG Vaccine in Niamey: Epidemiological, Diagnostic and Outcome Aspects

Introduction: Tuberculosis remains a public health problem worldwide. The BCG vaccination is one of response means. The objective of this work was to study impact of BCG vaccination on morbidity and mortality related to childhood tuberculosis in Niamey. Patients and methods: It was a multicenter prospective and comparative study from January to September 2017 in two-referral hospital centers of Niamey and the National Anti-Tuberculosis Center. The study population consisted exhaustively of children aged 0 to 15 years old suffering from tuberculosis. Epidemiological, diagnostic and evolving aspects in vaccinated and unvaccinated children were studied. Statistical tests used were Pearson's Chi² and Fisher's exact test (p <0.05). Results: Ninety-one children were studied. The BCG vaccination rate was 60.4%. The mean age of children was 6 years 11 months [3 months-15 years]. Children under 2 years of age were less affected (11%) in vaccinated children than in unvaccinated children (3.2%). No association was found between duration of tuberculosis signs (p = 0.37), expression of tuberculin skin test (p = 0.43), and the children's BCG vaccination status. On the other hand, there was a significant link between vaccination status and the results of microscopic examination of sputum or gastric fluid (p = 0.02), occurrence of complications (p = 0.014) and death risk (p = 0.003). Conclusion: This study shows that children’s BCG vaccination status interferes with some aspects of tuberculosis. Therefore, fighting against tuberculosis must be intensified, through combination of many strategies including vaccination

Tuberculosis in Vaccinated versus Unvaccinated Children with BCG Vaccine in Niamey: Epidemiological, Diagnostic and Outcome Aspects

Introduction: Tuberculosis remains a public health problem worldwide. The BCG vaccination is one of the response means. The objective of this work was to study the impact of BCG vaccination on morbidity and mortality related to childhood tuberculosis in Niamey. Patients and methods: It was a multicenter prospective and comparative study from January to September 2017 in two-referral hospital centers of Niamey and the National Anti-Tuberculosis Center. The study population consisted exclusively of children aged 0 to 15 years old suffering from tuberculosis. Epidemiological, diagnostic, and evolving aspects in vaccinated and unvaccinated children were studied. Statistical tests used were Pearson's Chi² and Fisher's exact test (p <0.05). Results: Ninety-one children were studied. The BCG vaccination rate was 60.4%. The mean age of children was 6 years 11 months [3 months-15 years]. Children under 2 years of age were less affected (11%) in vaccinated children than in unvaccinated children (3.2%). No association was found between the duration of tuberculosis signs (p = 0.37), expression of tuberculin skin test (p = 0.43), and the children's BCG vaccination status. On the other hand, there was a significant link between vaccination status and the occurrence of complications (p = 0.014), and death risk (p = 0.003). Conclusion: This study shows that children’s BCG vaccination status correlates with some aspects of tuberculosis. Unvaccinated children have a significantly higher risk of complications and death from TB

Impacts of Restoration Projects on a Sahelian Woody Vegetation after 21 Years: The Simiri Plateaus (Niger) Case Study

To face the soil and vegetation degradation in Niger, anti-erosion structures, such as scarification of the surface of the ground, half-moons, benches, trenches, stony cordons, were built in 1989 on three Simiri plateaus. Native and introduced woody species were planted and grasses were sown within the structures. This study aims at evaluating what has become the restoration of the woody vegetation cover compared to an un-restored woody cover located on a nearby similar site. Dendrometric parameters and alpha and beta diversities of the four woody stands in 36 sampled plots were analyzed and compared. The following dendrometric values were found significantly lower in the control than in the restored stands: 3.9% against 12.4-16.8% for the recovery rate, 4.3 against 6.3-10.2 cm for the largest stem diameter, 0.2 against 0.8-1.2 m²/ha for the basal area, and 1.6 against 2.0-2.5 m for the tree height. However, the number of stems per trees was found significantly greater in the un-restored stand (6.6) than in the restored ones (1.8-2.7). The values of dendrometric parameters remained low, as well as the alpha and beta diversities whatever the stand. Nevertheless, population perceptions on the restoration impacts that were collected through focus groups indicated positive impacts on downstream crop yields