Bananas

Did you know that the common bananas you get from the grocery store are all the same variety? The Cavendish is now the most common banana, although that was not always the case.

Until the later 19th century, the Gros Michelle was the most delicious and popular banana variety. Unfortunately, Panama disease (Fusarium oxysporum) decimated the global plantations growing the Gros Michel banana in the 1950’s and 1960’s, making a severe impact on the commercial industry. The fungus spreads through the soil, invading young roots and wounds, preventing plants from getting the nutrients they need. Vascular bundles infected by the Fusarium fungus turn brown or dark red, and leaves turn yellow, wilt, and collapse or hang downward, covering the trunk.

The Cavendish banana we know and enjoy today is now threatened itself, by a strain of Panama disease known as Tropical Race 4. There are ongoing efforts to breed highly disease resistant varieties in an attempt to control the spread of the disease, but, there is a bigger horticultural concern involved, as well. Monoculture – the cultivation of a single crop on agricultural or forest land – has a negative impact on a plant’s resistance to disease and pests. Biodiversity is the key to resilience of a species. Mono-cropping requires the use of chemicals that wind up killing undesirable pests and diseases as well as beneficial insects that support the ecosystem and fungi that would otherwise help plants naturally fight off pathogens.