By Abbas Nazil
Scientists have identified the most heat-tolerant plant ever documented, a desert species that not only survives but thrives in temperatures exceeding 120 degrees Fahrenheit in California’s Death Valley.
The plant, Tidestromia oblongifolia, commonly known as Arizona honeysweet, grows faster under extreme heat that would normally kill most other plants within hours.
Researchers say the discovery could transform efforts to develop crops capable of withstanding rising global temperatures and intensifying heat waves driven by climate change.
According to scientists at Michigan State University, the plant demonstrates that vegetation can adapt to far higher temperatures than previously believed.
The research team described Tidestromia oblongifolia as the most heat-tolerant plant ever studied, offering an unprecedented model for heat resilience.
Using advanced laboratory tools, researchers uncovered how the plant rewires its photosynthetic system to remain productive under extreme thermal stress.
Initial attempts to grow the plant in laboratory conditions failed, as standard environments were too mild compared to the harsh climate of Death Valley.
To overcome this, scientists built specialised growth chambers that replicated intense desert sunlight, extreme daytime heat and sharp temperature fluctuations.
Once these conditions were recreated, the plant’s growth surged dramatically, tripling its biomass in just ten days.
In contrast, other closely related heat-tolerant plants stopped growing altogether under the same extreme conditions.
The researchers found that Tidestromia oblongifolia rapidly adjusts its photosynthesis process when exposed to heat.
Within two days, the plant shifted its optimal temperature range, allowing photosynthesis to continue efficiently.
After two weeks, its optimal photosynthetic temperature reached about 113 degrees Fahrenheit, higher than any major crop species currently known.
At the cellular level, scientists observed striking changes in the plant’s internal structure.
Mitochondria moved closer to chloroplasts, improving energy efficiency and stabilising carbon use during heat stress.
Chloroplasts also reshaped into unusual cup-like forms never before seen in vascular plants.
These structural changes help the plant recycle carbon dioxide more efficiently, maintaining energy production even under extreme heat.
Thousands of genes were found to switch activity within 24 hours of heat exposure.
Many of these genes protect proteins, membranes and photosynthetic systems from heat damage.
The plant also increased production of Rubisco activase, a key enzyme that keeps photosynthesis functioning when high temperatures would normally shut it down.
As global temperatures continue to rise, heat stress is already reducing yields of essential crops such as wheat and maize.
Scientists say this discovery shifts long-standing assumptions about the limits of plant heat tolerance.
By identifying the genes and mechanisms behind honeysweet’s resilience, researchers now have concrete targets for breeding or engineering heat-tolerant crops.
The study’s authors caution that translating these traits into food crops will require extensive testing and time.
However, they believe lessons from this desert survivor could help safeguard global food supplies in a future defined by extreme heat.
The findings were published in the scientific journal, Current Biology.