Prévalence du dessèchement du manguier et evaluation de la fréquence des champignons associés à la maladie au Burkina Faso. Objectif : l'objectif de l'étude est de contribuer au diagnostic du dessèchement du manguier au Burkina Faso. Il s'agit d'une part d'évaluer l'incidence et la sévérité de la maladie sur cinq variétés commerciales provenant du Dianda et al, J. Appl. Biosci. 2018 Prévalence du dessèchement du manguier et evaluation de fréquence des champignons associés à la maladie au Burkina Faso.

Xanthomonas citri pv. mangiferaeindicae is the causal agent of bacterial canker of mango (Mangifera indica, Anacardiaceae), a disease of international importance. Since the original description of the bacterium in the 1940s, the status of cashew (Anacardium occidentale, Anacardiaceae) as a host species has been unclear. Here, we report the first outbreak of a cashew bacterial disease in Burkina Faso (Western Africa) where X. citri pv. mangiferaeindicae recently emerged on mango. A comprehensive molecular characterization, based on multilocus sequence analysis, supplemented with pathogenicity assays of isolates obtained during the outbreak, indicated that the causal agent on cashew in Burkina Faso is X. citri pv. mangiferaeindicae and not X. citri pv. anacardii, which was previously reported as the causal agent of a cashew bacterial leaf spot in Brazil. Pathogenicity data supported by population biology in Burkina Faso suggest a lack of host specialization. Therefore, the inoculum from each crop is potentially harmful to both host species. Symptoms induced on cashew leaves and fruit by X. citri pv. mangiferaeindicae and nonpigmented strains of X. citri pv. anacardii are similar, although the causative bacteria are genetically different. Thus, xanthomonads pathogenic on cashew may represent a new example of pathological convergence in this bacterial genus.

Mango decline is a serious disease in production areas in Burkina Faso. The aim of this study was to contribute to the management of the disease through the use of plant aqueous extracts. Antifungal activities of Azadirachta indica, Calotropis procera, Gmelina arborea, Jatropha curcas, Eucalyptus camaldulensis and the synthetic fungicide (Mancozeb) were tested against Lasiodiplodia theobromae and Lasiodiplodia pseudotheobromae associated to mango decline in Burkina Faso. Three different concentrations of leaf extracts which 25%, 50%, 75% and 500 ppm of Mancozeb were tested for their antifungal activity in vitro. The results showed that leaf extracts have an inhibitor effect on the growth of the two Lasiodiplodia species. The aqueous extract of G. arborea was the most effective with average inhibition rates of L. theobromae of 42.62%, 73.84% and 74.23% respectively with the concentrations of 25 g/l, 50 g/l and 75 g/l. The aqueous extract of A. indica against L. pseudotheobromae showed maximum percentage inhibition with 50 g/l of 63.10% and with 75 g/l of 72.02%. Mancozeb completely inhibits the mycelial growth of both species of fungi. Ours findings showed that aqueous extracts from plants could be tried for the eco-friendly management of mango decline pathogens.Keywords: Antifungal, plants extract, Lasiodiplodia spp., mango decline, Burkina Faso.

Bacterial wilt caused by the Ralstonia solanacearum species complex (RSSC) is a disease that negatively affects the cultivation of Solanaceae crops in Burkina Faso. Knowledge of the pathogen diversity is essential to deploy locally adapted control methods. In this study, diseased plants showing typical bacterial wilt symptoms were collected in the three main agroclimatic zones of Burkina Faso for the detection of RSSC isolates. Strain characterization was achieved through a phylogenetic and pathogenicity diversity assessment. A total of 102 isolates were sampled, and Phylotype I (Ralstonia pseudosolanacearum) was predominant (n = 101; sequevars 14, 31, 34, and 46). The remaining isolate was characterized as Phylotype IIA‐35 (Ralstonia solanacearum). Phylotypes I‐31 and I‐46 were predominant and both characterized as the most the aggressive group of strains amongst a subset of 33 representative isolates. Our findings provide valuable information as regard RSSC diversity that breeders and resistance programme should target in order to fight this pathogen in Burkina Faso and around the world.