The researchers -- HHMI investigator Joanne Chory and HHMI research associate Pablo D. Cerdn, both at The Salk Institute for Biological Studies -- reported their findings in an article published in the June 19, 2003, issue of the journal Nature.
"Few people realize that the biggest competitor for plants is other plants," said Chory. "Shade-avoidance syndrome is a series of developmental changes that the plant makes when it perceives that it's being shaded and, therefore, not getting enough photosynthetically effective light to thrive."
Under these conditions, a plant elongates its stem and restricts leaf development. "And then, if the plant is not successful, it produces what might be called a 'desperation flower,' and goes on to make only a few seeds that will ensure the survival of at least some offspring," said Chory.
According to Chory, the central question for researchers was whether the shade-avoidance syndrome was a distinct signaling pathway in the plant. "Everyone knew that plants perceive light quality because they have photoreceptors that are attuned to different wavelengths of light," she said. "So, while it was proposed that there was a light-quality pathway that induces early flowering in shade-avoidance, no one had identified a component of that pathway, and no one knew whether it existed as an independent pathway. It might have just been part of other control pathways such as the photoperiod pathway by which the plant senses seasonal change."