Isolation and identification of fungi responsible for leaf spots disease of mango (Mangifera indica linneaus) in Sokoto state, Nigeria

Abstract

A survey was carried out to investigate the incidence of fungal leaf spots disease of mango (Mangifera indica) in Sokoto metropolis using random sampling methods.  Field survey was carried out in six mango growing areas; Arkilla, Dambuwa, Gagi, Illela, More and permanent site of the Usmanu Danfodiyo University, Sokoto. Diseased plant leaves were identified using disease symptoms. A total of 125 healthy and diseased leaves were collected using detached leaf technique. The diseased plant leaves were taken to the laboratory for culture, isolation, and identification of pathogens. Plant disease incidence was determined using disease index and severity scale of 0-4 rating. Eleven fungal pathogens were isolated and identified. These included; Alternaria longipes,  Aspergillus fumigatus, Aspergillus niger, Colletotrichum gloesporioides, Fusarium oxysporum, Fusarium mangifera, Pestalotiopsis  mangiferae, Phoma mangiferae, Phomopsis mangiferae,  Pseudofusicoccum spp. and Rhizopus oryzae. The incidence of leaf blight was high in Usmanu Danfodiyo University, Sokoto with percentage frequency of (56.75%), followed by Dambuwa (45.50%), More  (44.48%), lllela (37.00%), Gagi (34.15%) and Arkilla (31.65%). Leaf spots intensity was more influenced by environmental  conditions and cultural practices rather than climatic factors in the areas. Also, programs aimed at enlightening the farmers on proper cultural practices and  boosting mango yield and reducing pathogen invasion are recommended.

Keywords: Incidence, Fungi, Leaf spot, disease, Mango, Sokoto.