Banana extinction rumours unpeeled

A plant pathologist with the American Phytopathological Society has largely dismissed rumours that bananas could face extinction within the next decade.

A plant pathologist with the American Phytopathological Society has largely dismissed rumours that bananas could face extinction within the next decade.

The pathologist has spoken out in response to an article which appeared recently in the New Scientist depicting possible extinction due to the impact of two diseases, Black Sigatoka and Panama disease, on the global production of bananas.

"Diseases are, and will remain, major constraints to both export and subsistence production of banana, and there is no doubt that Black Sigatoka and Panama disease constitute the most important threats," said Randy C. Ploetz, Professor at the University of Florida's Tropical Research and Education Center. "However, it is unlikely that these problems will cause production to decrease greatly in the next decade, let alone that the crop will become extinct."

According to Ploetz, Black Sigatoka affects diverse bananas used in subsistence agriculture, as well as the Cavendish cultivars that are used in export production. It is a serious foliar disease but does not kill plants, and is well controlled in export plantations with fungicides. In contrast, Panama disease is soil-borne and fatal. A new variant of the pathogen, tropical race 4, affects Cavendish cultivars in south east Asia and is thus at the root of concerns in the export trades.

The spread of tropical race 4 to the Americas would require either infected banana suckers or infested soil to be imported from Asia, both of which are strictly forbidden in the export-producing countries, said Ploetz. "If tropical race 4 did spread to the western hemisphere, damage would be restricted by the containment and eradication measures that would follow and the fact that the export trades rely on pathogen-free, tissue cultured plants to establish plantations" he said.

This statement follows a recent announcement from the UN Food and Agriculture Organisation (FAO) urging producers to diversify, as at present the majority of producers grow the same genotype of banana, the Cavendish. The FAO also mentioned genetic modification and biotechnology as possible solutions.

Ploetz said development of new hybrid bananas, as well as those produced via genetic transformation, must continue in order to supply producers with productive cultivars that resist important diseases, nematodes and insects.