Study Says Fruits Like Oranges & Lemons All Probably Originated in China

A sour fact to swallow.

Oct. 9, 2023

Study Says Fruits Like Oranges & Lemons All Probably Originated in China

A team of experts dealing with horticulture, genealogy, and plant genetics has determined with evidence that citrus fruits, including ones such as oranges, limes, and lemons, originated in the region that's now known as Southern China.

For now, we know that citrus fruits tend to grow in warm or tropical climates, with many of them produced via human cultivation. All the while, many people have suggested that these fruits might have originated in places such as Australia, the Himalayas, and maybe in some areas in China.

In the team's study published in Nature Genetics, the researchers studied 314 citrus and citrus-related plants, while performing fieldwork in previously unverified locations where citrus plants were believed to exist.

This approach enabled them to discover and categorize a substantial number of wild citrus species.

After using the data gathered from all these sources, they constructed a family tree representing the evolutionary history of citrus fruits.

Ultimately, their findings pointed to C. trifoliata as the oldest citrus species, dating back approximately eight million years, with its current habitat in southern China. This discovery suggests that the birthplace of citrus fruit may indeed be in southern China.

Interestingly, team hypothesizes that citrus fruit species in China could have dispersed to what is now India during the collision of the Asian and Indian tectonic plates around 25 million years ago. And then these citrus species might have further spread to regions surrounding the Mediterranean Sea.

As part of their research, the team identified the gene responsible for regulating citric acid levels in fruits, known as PH4. They observed that when this gene is activated, it triggers a proton pump mechanism that enhances citric acid production, consequently affecting the tartness of the fruit.