Le Banana Bunchy Top Disease (BBTD) est la maladie virale la plus dévastatrice du bananier impactant considérablement sa production. Le BBTD a été signalé au Gabon pour la première fois par la FAO avec une prévalence de plus de 90%. La présente étude vise à déterminer la prévalence du BBTD, la sévérité et l’importance du vecteur dans la zone de Ntoum. Après une enquête, 1800 pieds de bananiers dans 6 foyers d’infestation, ont été examinés de façon aléatoire avec un système de notation randomisé en transect croisé X. La méthode d’enquête par observation visuelle des symptômes du BBTD avec une échelle de notation de 1 à 5 a été utilisée. Les foyers d’infestation retenus présentent une sévérité de la maladie avancée avec le symptôme visuel de niveau 5 prépondérant et une prévalence moyenne de 21%. Le vecteur, Pentalonia nigronervosa est un insecte présent dans la zone mais à des niveaux d’importance variable. Il serait souhaitable d’évaluer la résistance variétale des Musa spp. et de montrer l’influence des facteurs biotiques et abiotiques sur la propagation de la maladie.Mots clés : Bananier, Pentalonia nigronervosa, foyers d’infestation, sévérité, importance du vecteur.   English Title: Prevalence of Banana Bunchy Top Disease (BBTD) in the Ntoum area in Gabon Banana Bunchy Top Disease (BBTD) is the banana's most devastating viral disease, with a significant impact on its production. BBTD was first reported in Gabon by FAO with a prevalence of more than 90%. This study aims to determine the prevalence of BBTD, the severity and importance of the vector in the Ntoum area. After a survey, 1800 feet of banana trees in 6 outbreaks, were examined randomly with a randomized scoring system in transect crossed X. The method of visual observation of BBTD symptoms with a rating scale of 1 to 5 was used. The selected outbreaks have an advanced disease severity with the predominant level 5 visual symptom and an average prevalence of 21%. The vector, Pentalonia nigronervosa is an insect present in the area but at varying levels. It would be desirable to assess the varietal resistance of Musa spp. and to show the influence of biotic and abiotic factors on the spread of the disease.Keywords: Banana, Pentalonia nigronervosa, source of infestation, severity, importance of vector.

Banana Bunchy Top disease is the most devastating viral disease that can attack bananas. Its presence prevents the development of bananas and leads to a decrease in production. It is caused by Banana Bunchy Top Virus (BBTV), the vector agent of which is the aphid aphid Pentalonia nigronervosa. The disease is present in the agroecological zone of the coastal sedimentary basin of Gabon, where the prevalence of the disease is reaching worrying proportions. This study focused on the assessment of varietal resistance of Musa spp. the most common in greater Libreville. The diversity of local banana cultivars can be an asset in the search for varieties resistant to BBTV. The results of this study show that not all cultivars have the same sensitivity. Indeed, dessert cultivars are more susceptible than plantain cultivars. Fougamou and Gros-Michel are the most widely cultivated dessert cultivars in greater Libreville, and are very sensitive to BBTV. Alone, these two cultivars failed to germinate after inoculation of pure ground material from a plant infested with BBTV at the highest stage of the disease. While the plantain cultivars, Obel, ZokEkone and Elate, are much more resistant.