Bacterial soft rot of banana

Abstract

Bacterial soft rots of banana and plantains involve two different diseases caused by related but distinct pathogens: rhizome soft rot or head rot by Pectobacterium carotovorum. subsp. carotovorum and pseudostem wet rot and rhizome rot - in some parts of the world called rhizome necrosis and corm rot-, caused by Dickeya paradisiaca. Although considered minor diseases, they cause losses of individual plants, yield reduction and raise the cost of production. Bacterial soft rots are found in wet humid soils with poor drainage, and high pH, during prolonged wet periods. Affected plants show poor shoot emergence, dwarfing, scorching of the lower leaves, and wilting and rot of the youngest emerging leaves. Rhizome infection causes a pseudostem wet rot progressing upward from infected rhizome and from petioles downward and a spongy necrotic collar at the union of rhizome with the pseudostem. Bacterial soft rot pathogens can be diagnosed by microbiological and molecular techniques. Disease management relies on use of healthy planting material, plant to plant tools disinfection and improving soil drainage and cropping practices.