Évaluation de la Variabilité Génétique d’Une Collection de Bananiers Plantain (Musa sp.) Cultivés en Côte d’Ivoire à Partir d’Une Caractérisation Agro-morphologique

La banane plantain est un produit de grande consommation en Côte d’Ivoire. Dans le but d’accroître les rendements par la création de variétés performantes, une bonne connaissance de la diversité des accessions existante est indispensable. Dans cette optique, la diversité agro-morphologique de la collection de bananiers du Centre National de Spécialisation plantain (CNS-Plantain) composée de 42 accessions a été analysée sur la base de 38 variables qualitatives et quantitatives selon le descripteur de l’IPGRI-INIBHP/CIRAD 1996. Les résultats ont montré des différences significatives entre les accessions au niveau morphologique, des caractères de production et des rendements. L’analyse en composantes principales (ACP) et la classification ascendante hiérarchique (CAH) ont montré une importante variabilité génétique et ont permis d’identifier 5 groupes de bananiers dans la collection. Le groupe des French (Groupe 1) et le groupe de banane à cuire de type ABB (Groupe 5) sont caractérisés par un nombre de mains élevés (6 à 16), des fruits courts et nombreux (53 à 192) et donc de gros régimes avec un long cycle de production pour les French. Le groupe des Faux-cornes (Groupe 3) possède 4 à 8 mains avec des fruits de taille moyenne et peu nombreux (14 à 57) et un cycle de production plus court. Les individus du groupe 2 (Bâtard) possèdent des fruits de taille et de nombre intermédiaire entre les French et les Faux-cornes. Dans le quatrième groupe (Vrai-cornes), les accessions sont caractérisées par des fruits de grande taille et peu nombreux (7 à 20). Cette diversité génétique offre ainsi une grande possibilité de choix de géniteurs pour la création de variétés améliorées de banane plantain en Côte d’Ivoire.   The plantain banana is a widely consumed product in Côte d'Ivoire. In order to increase yields by creating high-performance varieties, a good knowledge of the diversity of existing accessions is important. Thus, the agro-morphological diversity of the banana collection of the National Center for Plantain Specialization (CNS-Plantain) composed of 42 accessions was analyzed based on 38 qualitative and quantitative variables according to the IPGRI-INIBHP descriptor. /CIRAD 1996. The results showed significant differences between the accessions in terms of morphology, production traits and yields. Principal component analysis (PCA) and hierarchical ascending classification (HAC) showed significant genetic variability and identify 5 groups of bananas in the collection. The French group (Group 1) and the ABB-type cooking banana group (Group 5) are characterized by a high number of hands (6 to 16), short and more fruits (53 to 192), therefore a bigger bunch with a long production cycle for the French. The False horn group (Group 3) has 4 to 8 hands with medium-sized and few fruits (14 to 57) and a shorter production cycle. The accessions of group 2 (Bâtard) have fruits of intermediate size and number between the French and the False horns. In the fourth group (True horns), the accessions are characterized by large and few fruits (7 to 20). Thus, this genetic diversity offers a great possibility of choice of genitors for the creation of improved varieties of plantain in Côte d'Ivoire

INTER-FERTILITY AMONG FEMALE PARENT CLONES OF PINEAPPLE INVOLVED IN A 6X6 COMPLETE DIALLEL CROSSING SYSTEM BASED ON TYPOLOGICAL APPROACH

Pineapple ( Ananas comosus L. Merr) breeding programme in C\uf4te d\u2019Ivoire considers fruit diversification as key component in the international pineapple industry. The objective of this study was to determine the sexual compatibility of female pineapple clones recently developed in C\uf4te d\u2019Ivoire. Three female hybrid clones, 410-106-33, 410-200-15, 103-104-6; one variety, known as Queen Victoria RE43; as well as two Smooth Cayenne varieties HA10 and HA25 used as controls, were tested in this study. They were inter-crossed according to a 6x6 complete diallel mating system with selfings. Results showed that female hybrid clone 410-200-15, was the least inter-compatible; implying that it can be indifferently cultivated in single or mixed-crop fields. This was followed by the genitors RE43 and 410-106-33. The response pattern could be due to the relatedness existing among these three clones. Conversely, hybrid clone 103-104-6 was the most inter-compatible. In this case, it needs to undergo successive back-crosses, using the parent HA10 as donor, before on-farm evaluations. The female clones 410-106-33 and RE43 produced the heaviest and the lightest fruits, respectively.Le programme d\u2019am\ue9lioration g\ue9n\ue9tique de l\u2019ananas ( Ananas comosus L.) en C\uf4te d\u2019Ivoire consid\ue8re la diversification fruiti\ue8re comme une composante cl\ue9 pour l\u2019industrie internationale de l\u2019ananas. L\u2019objectif de la pr\ue9sente \ue9tude \ue9tait de d\ue9terminer la compatibilit\ue9 sexu\ue9e de clones femelles d\u2019ananas r\ue9cemment cr\ue9es en C\uf4te d\u2019Ivoire. Trois clones hybrides femelles d\ue9sign\ue9s 410-106-33, 410-200-15, 103-104-6, une vari\ue9t\ue9, connue sous le vocable de Queen Victoria RE43, ainsi que deux vari\ue9t\ue9s Cayenne lisse HA10 et HA25 utilis\ue9s comme t\ue9moins, ont \ue9t\ue9 test\ue9s dans cette \ue9tude. Ils ont \ue9t\ue9 inter-crois\ue9s selon un plan de croisements diall\ue8le complet 6 x 6 avec autof\ue9condations. Les r\ue9sultats ont montr\ue9 que le clone hybride femelle 410-200-15 a \ue9t\ue9 le moins inter-compatible, sugg\ue9rant qu\u2019il peut \ueatre cultiv\ue9 indiff\ue9remment en parcelles mono ou multiclonales. Il a \ue9t\ue9 suivi par les g\ue9niteurs RE43 et 410-106-33. Un tel comportement pourrait \ueatre d\ufb \ue0 la parent\ue9 existant entre ces trois clones. A l\u2019oppos\ue9, le clone hybride 103-104-6 a exprim\ue9 la plus haute inter-compatibilit\ue9. Il devrait \ueatre soumis \ue0 des back crosses successifs, utilisant le parent HA10 comme donneur, avant les \ue9valuations en milieu r\ue9el. Les clones femelles 410-106-33 et RE43 ont produit respectivement les fruits les plus lourds et les plus l\ue9gers

MGIS: managing banana (Musa spp.) genetic resources information and high-throughput genotyping data

Unraveling the genetic diversity held in genebanks on a large scale is underway, due to advances in Next-generation sequence (NGS) based technologies that produce high-density genetic markers for a large number of samples at low cost. Genebank users should be in a position to identify and select germplasm from the global genepool based on a combination of passport, genotypic and phenotypic data. To facilitate this, a new generation of information systems is being designed to efficiently handle data and link it with other external resources such as genome or breeding databases. The Musa Germplasm Information System (MGIS), the database for global ex situ-held banana genetic resources, has been developed to address those needs in a user-friendly way. In developing MGIS, we selected a generic database schema (Chado), the robust content management system Drupal for the user interface, and Tripal, a set of Drupal modules which links the Chado schema to Drupal. MGIS allows germplasm collection examination, accession browsing, advanced search functions, and germplasm orders. Additionally, we developed unique graphical interfaces to compare accessions and to explore them based on their taxonomic information. Accession-based data has been enriched with publications, genotyping studies and associated genotyping datasets reporting on germplasm use. Finally, an interoperability layer has been implemented to facilitate the link with complementary databases like the Banana Genome Hub and the MusaBase breeding database. Database URL:https://www.crop-diversity.org/mgis

Promising High-Yielding Tetraploid Plantain-Bred Hybrids in West Africa

The devastating threat of black leaf streak disease caused by Pseudocercospora fijiensis on plantain production in West Africa spurred the development of resistant hybrids. The goal of this research and development (R&D) undertaken was assessing the development and dissemination of two plantain hybrids PITA 3 and FHIA 21 bred in the 1980s by the International Institute of Tropical Agriculture (IITA, Nigeria) and the Fundaci ́on Hondureña de Investigacion Agŕıcola (FHIA, Honduras), respectively. In Cote d’Ivoire, plantain growers selected PITA 3 and FHIA 21 based on their improved agronomic characteristics and, between 2012 and 2016, they were massively propagated and distributed to farmers in Benin, Burkina Faso, Cote d’Ivoire, and Togo under the West Africa Agricultural Productivity Program (WAAAP) coordinated by the West and Central Africa Council for Agricultural Research and Development (CORAF). In 2016, the Centre National de Recherche Agronomique in Cote d’Ivoire included the hybrids in the improved cultivar directory. This R&D activity illustrates how three decades of crossbreeding, selection, and distribution led to local acceptance. It also highlights how a CORAF-led partnership harnessed CGIAR research for development. The dissemination and acceptance of these plantain hybrids will enhance the sustainable intensification in plantain-based farming systems across the humid lowlands of West and Central Africa

Promising high-yielding tetraploid plantain-bred hybrids in west Africa

Open Access Journal; Published online: 21 April 2019The devastating threat of black leaf streak disease caused by Pseudocercospora fijiensis on plantain production in West Africa spurred the development of resistant hybrids. The goal of this research and development (R&D) undertaken was assessing the development and dissemination of two plantain hybrids PITA 3 and FHIA 21 bred in the 1980s by the International Institute of Tropical Agriculture (IITA, Nigeria) and the Fundación Hondureña de Investigación Agrícola (FHIA, Honduras), respectively. In Côte d’Ivoire, plantain growers selected PITA 3 and FHIA 21 based on their improved agronomic characteristics and, between 2012 and 2016, they were massively propagated and distributed to farmers in Benin, Burkina Faso, Côte d’Ivoire, and Togo under the West Africa Agricultural Productivity Program (WAAAP) coordinated by the West and Central Africa Council for Agricultural Research and Development (CORAF). In 2016, the Centre National de Recherche Agronomique in Côte d’Ivoire included the hybrids in the improved cultivar directory. This R&D activity illustrates how three decades of crossbreeding, selection, and distribution led to local acceptance. It also highlights how a CORAF-led partnership harnessed CGIAR research for development. The dissemination and acceptance of these plantain hybrids will enhance the sustainable intensification in plantain-based farming systems across the humid lowlands of West and Central Africa

Effects of Peat and Chiken Litter on Three Cultivars of Plantain in Plants Vivo: FHIA 21, PITA 3 and Horn 1

Aims: This study was carried out to test various substrates made of a mixture of earth with different proportions of organic fertilizing substances to improve the technique of mass production of plantain plantain material, and the multiplication of shelled strains (MSD). Place and Duration of Study: The study of the growth and development of plantain cultivars FHIA 21, PITA 3 and Horn 1 was carried out in the region of Azaguié, at the production station of plantain banana (Musa pardisiaca) plants of the National Center for Agricultural Research (CNRA) under tunnel and shade for a period of 8 months. Methodology: The substrates tested were chicken litter and peat mixed with soil in 25%, 50% and 75% proportions. Our study took place from March to November 2014. Results: For tunnel results, S7 (soil 25% - mature chicken litter 75%) and S6 (soil 50% - mature chicken litter 50%) had positive impacts on the height of the three cultivars, particularly Horn 1 while the dry matter was improved by the substrate S1 earth (100%). The S7 substrate allowed good root production regardless of the cultivar and also increased root branching levels. Under the shade, substrates S7 and S6 negatively influenced the height. The number of roots and the degree of branching of the roots were improved by the substrates S2 (50% earth - 50% peat) and S3 (25% earth - 75% peat). The amounts of dry matter fluctuated without any significant difference. The influence of the two environments on the development and growth parameters of the in vivo plants revealed that the highest values were obtained under tunnel with the exception of the dry matter. Conclusion: This study confirmed that, there was influence of substrates on the growth and development of plantain banana plants. Substrate S7 gave the best result under tunnel and under shaded substrates S2 and S3. In both environments, S7 substrates had a positive effect on the number of roots emitted

Etude de l’effet de l’électropolissage sur la résistance à la rupture en fatigue cyclique et sur l’état de surface d’instruments endodontiques

National audienceThe Nickel-titanium (Ni-Ti) instruments superelasticity does not does not allow to anticipate rupture.Aim: This study evaluates the effect of electropolishing time on the rupture resistance in flexion fatigue of the endodontics Ni-Ti instruments.Methods: 48 HeroShapers® 6% 25/100 are divided into 4 groups of surface treatment (without electropolishing, with electropolishing of 70, 80 or 90 seconds). The surface of the instruments is observed under a scanning electron microscope. Each instrument is driving by an inGet control motor at 275 rpm and put on a fatigue bench (stainless steel pipe angled at 60° with r = 10 mm). The number of turn before rupture is recorded by a specific meter. Data were analysed by analysis of variance and a Fischer probable least-square difference test (PLSD) at a significance level of 0.05.Results: The mean number of rotation to failure in each group of instrument decreases (407 to 355 tours) with the increase of the electropolishing time. There were no statistically significant difference (p = 0, 3508) between the different groups.Conclusion: Electropolishing from 70 till 90 seconds improves the surface state without modifying the rupture resistance in flexion fatigue of triple helix endodontic instruments with 6% taper.La super élasticité des instruments en Ni-Ti ne permet pas d’anticiper leur rupture.Objectif : Cette étude évalue l’effet du temps d’électropolissage sur la résistance à la rupture en fatigue de flexion des instruments endodontiques en Ni-Ti.Matériel et méthode : 48 HeroShaper® (Micro-Méga, Besançon, France) 6% (conicité) 25/100 (diamètre apical) sont répartis en quatre groupes d’état de surface (sans électropolissage, avec électropolissage de 70, 80 ou 90 secondes). L’état de surface des instruments est observé au microscope électronique à balayage. Chaque instrument est entraîné par un moteur InGet Control à 275 tr/mn et monté sur un banc de fatigue (tube acier creux, coudé à 60° avec r = 10 mm). Le nombre de tour avant la rupture est enregistré par un compteur spécifique. L’analyse de la variance et les tests a posteriori de Fischer sont ensuite réalisés avec un risque a de 5%.Résultats : Le nombre de tour moyen réalisé par chaque groupe d’instrument décroît (407 à 355 tours) avec l’augmentation du temps d’électropolissage. L’ANOVA montre qu’il n’y a pas de différence statistiquement significative (p = 0,3508) entre les différents groupes.Conclusion : L’électropolissage, de 70 à 90 secondes, d’instruments endodontiques à profil de triple hélice, de conicité 6%, améliore leur état de surface sans modifier leur résistance à la rupture en fatigue de flexio

INTER-FERTILITY AMONG FEMALE PARENT CLONES OF PINEAPPLE INVOLVED IN A 6X6 COMPLETE DIALLEL CROSSING SYSTEM BASED ON TYPOLOGICAL APPROACH

Pineapple ( Ananas comosus L. Merr) breeding programme in Côte d’Ivoire considers fruit diversification as key component in the international pineapple industry. The objective of this study was to determine the sexual compatibility of female pineapple clones recently developed in Côte d’Ivoire. Three female hybrid clones, 410-106-33, 410-200-15, 103-104-6; one variety, known as Queen Victoria RE43; as well as two Smooth Cayenne varieties HA10 and HA25 used as controls, were tested in this study. They were inter-crossed according to a 6x6 complete diallel mating system with selfings. Results showed that female hybrid clone 410-200-15, was the least inter-compatible; implying that it can be indifferently cultivated in single or mixed-crop fields. This was followed by the genitors RE43 and 410-106-33. The response pattern could be due to the relatedness existing among these three clones. Conversely, hybrid clone 103-104-6 was the most inter-compatible. In this case, it needs to undergo successive back-crosses, using the parent HA10 as donor, before on-farm evaluations. The female clones 410-106-33 and RE43 produced the heaviest and the lightest fruits, respectively.Le programme d’amélioration génétique de l’ananas ( Ananas comosus L.) en Côte d’Ivoire considère la diversification fruitière comme une composante clé pour l’industrie internationale de l’ananas. L’objectif de la présente étude était de déterminer la compatibilité sexuée de clones femelles d’ananas récemment crées en Côte d’Ivoire. Trois clones hybrides femelles désignés 410-106-33, 410-200-15, 103-104-6, une variété, connue sous le vocable de Queen Victoria RE43, ainsi que deux variétés Cayenne lisse HA10 et HA25 utilisés comme témoins, ont été testés dans cette étude. Ils ont été inter-croisés selon un plan de croisements diallèle complet 6 x 6 avec autofécondations. Les résultats ont montré que le clone hybride femelle 410-200-15 a été le moins inter-compatible, suggérant qu’il peut être cultivé indifféremment en parcelles mono ou multiclonales. Il a été suivi par les géniteurs RE43 et 410-106-33. Un tel comportement pourrait être dû à la parenté existant entre ces trois clones. A l’opposé, le clone hybride 103-104-6 a exprimé la plus haute inter-compatibilité. Il devrait être soumis à des back crosses successifs, utilisant le parent HA10 comme donneur, avant les évaluations en milieu réel. Les clones femelles 410-106-33 et RE43 ont produit respectivement les fruits les plus lourds et les plus légers