Yam (Dioscorea spp) occupies an important place in the diet of the populations of Côte d’Ivoire. It is a real source of starch and therefore generates enormous commercial potential. However, the decrease in production due to pest attacks represents a real threat to this crop. This study was conducted with the aim of improving yam production in Côte d’Ivoire. To do so, isolations carried out on yam leaves showing symptoms of foliar diseases have allowed us to identify 9 fungal genera. These were Colletotrichum sp., Fusarium sp., Pestalotiopsis sp., Pestalotia sp., Botryodiplodia sp., Aspergillus sp., Mucor sp., Curvularia sp. and Phytophtora sp. Among these fungi, the genus Colletotrichum sp. was the most isolated with a rate of 56% followed by the Fusarium and Pestalotia genera (8%). Pathogenicity tests performed on healthy leaves of two yam varieties revealed that the Dioscorea alata is more susceptible to fungi compared to Dioscorea rotundata. The largest average diameter of necrosis was caused by Pestalotiopsis sp. (5.97 cm) on the Dioscorea alata variety while the smallest was caused by Colletotrichum sp.9 on Dioscorea rotundata (0.5 cm). Combatting these fungi need to be developed for effective management of leaf diseases of yam in Côte d’Ivoire.

Mushrooms contain a variety of secondary metabolites, including various phenolic compounds, which have been shown to act as excellent antioxidants. In this study, the contents of total phenolic, flavonoids and tannins of mushrooms methanolic extracts were evaluated by colorimetric assays to ranges of 277.36±0.66 to 420.86±0.90 mg (GAE)/100g DW; 31.99±0.90 to 90.90±0.07mg (QE)/100g DW and 150.61±0.16 to 220.47±1.01mg (TAE)/100g DW respectively. HPLC-profiles of methanolic extracts indicated that the individual phenolic compounds found to the samples of the species of mushrooms that are Lentinus squarrosulus and Auricularia politrich revealed us that gallic acid, catechin, acid ρ-hydroxybenzoїc, acid ellagique and naringerin were presented to the level of the two species. With respect to organic acids, the results showed that citric acid and fumaric acid was the major organic acid in all the samples of both mushrooms species. The methanolic extracts of the two mushrooms exhibited the high DPPH radical scavenging activities ranging from 34.10±1.12 to 58.95±0.52%. These data indicated that these mushrooms could constitute a potential good source of natural antioxidant for the local population.