Jan. 14 (UPI) -- Scientists have figured out how plants sense temperature and adjust their physiology accordingly. The breakthrough could help researchers design more resilient and higher-yielding crop varieties.
Temperatures affect plant biology in numerous ways, altering flowering time, crop yield, disease resistance and more.
"It is important to understand how plants respond to temperature to predict not only future food availability but also develop new technologies to help plants cope with increasing temperature," Meng Chen, associate professor of cell biology at the University of California, Riverside, said in a news release.
Scientists used rockcress, Arabidopsis, a genus of small flowering plants related to mustard and cabbage, to investigate genetic pathways that respond to temperature.
Previous research efforts showed rockgress senses temperature increases in the evening, but in the wild, the winter plant rarely encounters rising evening temperatures.
"This has always been puzzling to us," Chen said. "Our understanding of the phytochrome signaling pathway is that it should also sense temperature during the daytime, when the plant would actually encounter higher temperature."
New lab experiments -- detailed in the journal Nature Communications -- showed the plants grow at different parts of the day during different seasons.
Previous research efforts showed winter conditions increase activity in the phytochrome signaling pathway known as phytochrome B. For the new experiments, Chen and his colleagues studied phytochrome B activity under red light at both 21 and 27 degrees Celsius.
"Under these conditions, we see a robust response," Chen said. "The work shows that phytochrome B is a temperature sensor during the day in the summer. Without this photoreceptor, the response in plants is significantly reduced."
Tests also revealed the importance of HEMERA, a transcription activator that dictates communications between temperature sensing and plant growth signaling.
"We found the master control for temperature sensing in plants," Chen said. "HEMERA is conserved in all plants, from moss to flowering plants."
Scientists can't be certain that all plants use phytochrome B and HEMERA to sense and respond to light and temperature conditions during the day, but because the signaling pathways are present in all plants, researchers think all plant species use genetic mechanisms similar to those deployed by rockcress.
Researchers hope future tests under more dynamic conditions will reveal new details about the way plants use phytochrome B and HEMERA to respond temperature changes. Eventually, scientists hope to manipulate genetic signaling pathways to design more resilient and productive crops.
"To cope with rapid temperature changes associated with global warming, we may have to help nature to evolve crops to adapt to the new environment," Chen said. "This will require a molecular understanding of how plants sense and respond to temperature."