How Global Warming Could Make Broccoli Look More Like Cauliflower

While it’s usually easy to tell the difference between broccoli and cauliflower by the color of the food alone, that trick may one day no longer work. In fact, climate change could cause some broccoli heads to lose their green hue and look more like cauliflower, a recent study suggests.

Is green broccoli on its way out? Recent research highlights the risks of high temperatures caused by climate change, which could cause a change in the color of this vegetable. According to the study, published in the journal Molecular Horticulture by researchers at Cornell University in the US, broccoli develops normally when the average growing temperature is 62°F (about 16°C). However, its crown begins to become deformed as soon as the mercury exceeds 72, °F (or about 22 °C). And, if the plant is exposed to temperatures of 82°F (about 28°C) or higher, it forms dense cauliflower-like heads called curds.

The scientists’ findings suggest that a process called DNA methylation lies behind the abnormal growth of broccoli at higher temperatures. By applying a chemical called 5-azacytidine, known to inhibit the process, they found that normal broccoli heads grew even at temperatures of 82°F.

However, further research will be needed to determine the exact mechanism associated with the abnormal growth of broccoli when exposed to high temperatures. “Once we understand the mechanism better, we should be able to devise ways to develop a new biotechnology, a molecular genetics approach to suppress DNA methylation, in order to breed crops to grow in much warmer temperatures and in wider regions,” said Susheng Gan, professor in the School of Integrative Plant Science Plant Biology Section, in the College of Agriculture and Life Sciences, and a co-corresponding author of the paper.

Broccoli isn’t the only thing in the natural world that could undergo a change in appearance due to climate change. A study published in 2022 showed that blue tits in the south of France had gradually lost the color of their plumage over a period of 15 years. Meanwhile, the increase in water temperature caused by global warming could give a green tint to lakes due to the proliferation of algae.