In California's Death Valley, Tidestromia oblongifolia thrives where temperatures exceed 120 degrees Fahrenheit. Michigan State University researchers discovered the plant adjusts its photosynthetic system to grow more quickly under such conditions. Their findings, published in Current Biology, could help develop heat-tolerant crops amid climate change.
Tidestromia oblongifolia, a native plant in Death Valley, California, not only survives but flourishes in summer heat surpassing 120 degrees Fahrenheit. Scientists at Michigan State University's Plant Resilience Institute, led by Research Foundation Professor Seung Yon "Sue" Rhee and Research Specialist Karine Prado, investigated how this species persists in such extremes.
The study, published in Current Biology, reveals that T. oblongifolia fine-tunes its photosynthetic system to resist heat damage, enabling faster growth. Prado noted the initial challenges: "When we first brought these seeds back to the lab, we were fighting just to get them to grow. But once we managed to mimic Death Valley conditions in our growth chambers, they took off."
Using custom growth chambers to replicate desert light and temperature shifts, the team found that in just 10 days, T. oblongifolia tripled its biomass, while related heat-tolerant species ceased growing. After two days of extreme heat, the plant expanded its photosynthetic comfort zone. Within two weeks, its optimal temperature for photosynthesis reached 45 degrees Celsius (113 degrees Fahrenheit), surpassing any major crop.
Rhee described it as "the most heat-tolerant plant ever documented." The plant's adaptations include mitochondria moving closer to chloroplasts for energy efficiency, and chloroplasts reshaping into unique "cup-like" forms to better capture carbon dioxide. Within 24 hours of heat exposure, thousands of genes activate protective functions, including increased production of Rubisco activase to maintain photosynthesis.
These mechanisms offer strategies for crops like wheat, maize, and soybeans, whose yields are declining due to expected global temperature rises of up to 5 degrees Celsius by century's end. Rhee emphasized, "T. oblongifolia shows us that plants have the capacity to adapt to extreme temperatures." She added, "Desert plants have spent millions of years solving the challenges we're only beginning to face."
The research shifts focus from model species like Arabidopsis to resilient desert plants, using tools like genomics and live imaging to enhance agricultural resilience.