Experts from the University of California and the Netherlands discovered three fungal diseases have now evolved into one deadly new threat to the world crop. The Cavendish banana plants all originated from one plant and so as clones, they all have the same genotype which is why they are so vulnerable to disease. “We have demonstrated that two of the three most serious banana fungal diseases have become more virulent by increasing their ability to manipulate the banana’s metabolic pathways and make use of its nutrients,” said UC Davis plant pathologist Ioannis Stergiopoulos. These fungal diseases are now called “Sigatoka complex” comprising of Mycosphaerella fijiensis (causal agent of black leaf streak disease), M. musicola (causal agent of yellow Sigatoka disease), and M. eumusae (causal agent of eumusae leaf spot disease). Disease diagnosis in the Mycosphaerella complex of banana is based on the presence of host symptoms and fungal fruiting structures, which hamper preventive management strategies. The exact distribution of these three species and their disease epidemiology remain unclear because their symptoms and life cycles are rather similar.
Phytopathology 2007 97:9, 1112-111811.21.16