According to recent research, climate change has increased the risk of a fungal disease that ravages banana crops.
Black Sigatoka disease emerged from Asia in the late twentieth century and recently completed its invasion of banana growing areas in Latin America and the Caribbean.
The new study, conducted by the University of Exeter, says that changes in humidity and temperature conditions have increased the risk of black Sigatoka by more than 44% in these areas since the 1960s.
International trade and increased banana production have also helped the spread of black Sigatoka, which can reduce the fruit produced by infected plants by up to 80%.
“Black Sigatoka is caused by a fungus (Pseudocercospora fijiensis) whose life cycle is strongly determined by climate and microclimate,” said Dr. Daniel Bebber of the University of Exeter.
“This research shows that climate change has improved temperatures for germination and growth of spores and has made crop cups more humid, which increases the risk of Black Sigatoka infection in many crop growing areas. banana in Latin America.
“Despite the overall increase in the risk of Black Sigatoka in the areas we examined, the drier conditions in parts of Mexico and Central America have reduced the risk of infection.”
The study combined experimental data on black Sigatoka infections with detailed information on climate over the past 60 years.
Black Sigatoka, which is virulent against a wide range of banana plants, was reported for the first time in Honduras in 1972.
It spread throughout the region to reach Brazil in 1998 and the Caribbean islands of Martinique, Saint Lucia and Saint Vincent and the Grenadines in the late 2000s.
The disease now occurs as far north as Florida.
“While it is likely that fungi were introduced into Honduras in plants imported from Asia for breeding research, our models indicate that climate change over the past 60 years has exacerbated its impact,” said Dr. Bebber.
The fungus Pseudocercospora fijiensis spreads through aerial spores, infecting the banana leaves and causing lesions of stripes and cell death when the fungal toxins are exposed to light.
The study did not attempt to predict the potential effects of future climate on the spread and impact of black Sigatoka. Other research suggests that drying trends could reduce the risk of disease, but this would also reduce the availability of water for banana plants.
The article, published in the journal Philosophical Transactions of the Royal Society B, is entitled: “Effects of climate change on the disease of black sigatoka of banana”.