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Mango production in Senegal takes place over the two seasons of dry and humid conditions between April and November. The increasing demand for fresh mangoes has led to an increase in land areaallocated to that crop. Mango production suffers, however, from fruit rotting due to post-harvest diseases during ripening. These diseases reduce the fruit quality and cause severe losses. A surveywas carried out in 2004 to detect fungi involved in post-harvest rot of mangoes (cv. Kent) produced in the Niayes area of Senegal in relation with the production practices and the climatic conditions. Theresults showed that at first harvest during the dry season, a broader species range of fungi including Alternaria sp., Botryodiplodia theobromae, Dothiorella sp., Aspergillus niger and non-identified fungiwere responsible for mango rotting. The fruits harvested during the humid season, however, were more heavily infested but a smaller number of fungal agents were involved; Colletotrichum gloeosporioidesand secondarily Phoma mangiferae played the main role. The cultural practices played an important role on mango infection whereby orchard sanitation and particularly cleaning and pruning reduced theinfection rates. Orchards with no care, in contrast, yielded the most heavily infested mango samples. In addition, the harvest practice of inversion of fruits in soil for sap elimination increases contaminationwith pathogenic fungi.

L'influence de la température et de quelques fongicides a été utilisée pour la caractérisation in vitro de Colletotrichum gloeosporioides. L'étude de l'influence de la température sur la croissance in vitro et la germination des spores de C. gloeosporioides, champignon phytopathogène, responsable de l'anthracnose du manguier, a montré que les températures 25 et 30 °C sont plus favorables aussi bien pour le développement mycélien que pour la germination des spores. Le test de différents fongicides incluant l'azoxystrobine, le chlorothalonil, l'imazalil, l'oxychlorure de cuivre, le thiophanate méthyl, le myclobutanil, le mancozèbe et le manèbe a montré l'efficacité marquée du myclobutanil et du chlorothalonil pour le contrôle in vitro de la croissance mycélienne. En effet, ces fongicides ont présenté des DL50 inférieures à 1 ppm. L'imazalil, l'azoxystrobine et le mancozèbe ont montré des DL50 respectives de 1,5, 1,7 et 5,3 ppm. Pour la germination des spores l'imazalil et le chlorothalonil inhibent totalement la germination des spores à 50 ppm tandis que pour l'oxychlorure de cuivre le mancozèbe et le manèbe cette inhibition a été notée à 100 ppm.For in vitro characterization of the fungal pathogen Colletotrichum gloeosporioides, responsible for mango anthracnose, the influence temperatures and selected fungicides has been tested on mycelial growth and spore germination. The results showed that 25 °C and 30 °C are more suitable for mycelial growth as well as for spore germination. The fungicide tests involving azoxystrobin, chlorothalonil, imazalil, copper oxychoride, thiophanate-methyl, myclobutanil, mancozeb and maneb showed a marked efficiency of myclobutanil and chlorothalonil for in vitro inhibition of mycelial growth. These two fungicides presented a DL50 below 1 ppm and were therefore classified as very efficient. Imazalil, azoxystrobine and mancozeb with a higher DL50, respectively 1,5, 1,7 and 5,3 ppm were classified as efficient. For spores germination, imazalil and chlorothalonil inhibited totally spores germination at 50 ppm whereas for copper oxychloride, mancozeb and maneb a complete inhibition was obtained at 100 ppm. Keywords: Colletotrichum gloeosporioides, croissance in vitro, température, fongicides, manguier; Colletotrichum gloeosporioides, mycelial growth, temperature, fungicides, mango. Journal des Sciences Pour l\'Ingénieur. Vol. 9 2008: pp. 21-27