Melon enthusiasts have spent decades tracing the origins of the common watermelon, a popular fruit that has influenced cultures around the world for thousands of years. And now DNA tests have revealed its oldest ancestor, the Sudanese Kordofan melon.
Before Susanne S. Renner and her team of researchers began sequencing the DNA of non-domestic plants in the watermelon genus (Citrullus), most botanists agreed that the watermelon originated in the South Americas. African lemon melon. This hypothesis, first introduced by a student of taxonomist Carl Linneaus who visited Cape Town 1
DNA testing showed that the South African lemon melon is very different from the regular watermelon we find in supermarkets today. Instead, its closest wild relative appears to be the Sudanese Kordofan melon, a white-fleshed fruit. The inside may not look appetizing, but the Kordofan is not too bitter and can be eaten raw, making it the perfect candidate for domestication. (Watermelons with white pulp were common until recently. You can still buy heirloom watermelons with white pulp!)
Studying the origin of watermelons may seem like a futile task, but it could help protect the watermelon from extinction. Modern farming practices have severely limited the gene pool of watermelons (and other edible plants), meaning nearly all watermelons share the same genetic vulnerability to diseases, pests, and fungi. The Kordofan melon could help us diversify the watermelon gene pool, or at the very least help us figure out what genetic protection the watermelon lost through domestication.
Source: PNAS via Smithsonian