Efficacité des extraits de plantes dans la lutte contre les champignons responsables des pourritures de tubercules d’igname en stockage dans les magasins du marché de gros de bouaké (Côte D’ivoire)

Yam (Dioscorea spp.) is a staplefoodthatoccupies a prominent place in the diet of the Ivorian population. However, its conservation isprey to numerousattacks due in major part to fungi. The objective of the studywas to evaluate the efficacy of aqueous plant extracts on the growth of fungal pathogensresponsible for storage rots of yam tubers. The approachconsisted of sampling yam stocks at the Bouaké wholesale market followed by identification of the microfloraassociated with rots and theirpathogenicity. Antifungal tests were performed with different concentrations of aqueous plant extracts to evaluate the irantimicrobial potential against fungal strains isolated and identified from symptomatic yam tubers. The identification results revealed that the identified fungal species consisted of Aspergillus niger, Aspergillus flavus, Colletotrichum gloeosporioides, Colletotrichum sp., Fusarium oxysporum, Penicillium oxalicum, Rhizopus stolonifer and Rhizopus microsporus. Pathogenicity tests were performed with the major fungal strains (Isolation Frequency ≥ 12%). The tests highlighted the susceptibility of the variety "Kponan", with a rot volume of 78.70 cm3. Penicillium oxalicum species showed high pathogenic activity resulting in an average decay volume of 74.64 cm3. Aqueous extract tests of Zingiber officinale and Hyptis souaveolens showed more than 50% inhibitory effect on mycelial growth of most fungi (Penicillium oxalicum, Fusarium oxysporum, Colletotrichum gloesporioides and MBF). Extracts of Z. officinale and H. suaveolens could thus constitute a possible solution against agents involved in yam rots in stock.