Post Harvest Rot of Cocoyams Obtained From Rivers and Bayelsa States of Nigeria.

Abstract

The incidence of Fungi on Post Harvest Cocoyam cultivars in three zones within Rivers and Bayelsa states namely, Coastal Plain Sands (Igbo and Baen), Warri Sombreic Deltaic Plain (Obrikom and Ahoada) and Meander Belt (Agudama and Kaiama) was studied. Four cocoyam cultivars were used for the study namely, Xanthosoma mafaffa (Ede uhie and Ede ocha) cultivars and a(Cocoindia and Ede nwachukwu) cultivars. The following micro-organisms of rot of the roots and corms (Cocoyam Decline Disease) were isolated. From X.mafaffaEde uhie, Mucor sp, Rhizopus stolonifer, Fusarium spand Aspergillus niger.Aspergillus flavus, Rhizopus stolonifer, Fusarium spand Aspergillus flavus were isolated from X.mafaffac.v Ede ocha. From C.esculentac.v (Coco India),Aspergillus flavus, Aspergillus niger, Rhizopus stolonifer and Mucor sp, while Mucor sp, Rhizopus stoloniferand Aspergillus niger were isolated from Colocasia esculentac.v. Ede nwachukwu.Most of the fungi isolated from the corms were present in the soil. Susceptibility of the cocoyam cultivars, X.mafaffa (Ede uhie and Ede ocha) and C.esculenta (Cocoindia and Ede nwachukwu) to the isolates of the corm rot pathogens was tested. The severity of the rot was highest in C.esculenta (coco india),X.mafaffa(Ede ocha),X.mafaffa (Ede uhie) and C.esculenta (Ede nwachukwu),X.mafaffa(Ede uhie and Ede ocha) and C.esculenta (coco india) were most susceptible to Aspergillus niger while C.esculenta (Ede nwachukwu) was most susceptible to Mucor sp.