“How do organisms decide when to grow and when to stop growing? These questions are especially important in plants because they are rooted in the ground and must alter their shape and size in response to their local environment. Thus, it’s a question of survival,” added Chory. “It took us 10 years to develop the tools to ask the question. It is very satisfying for me to see the results.”
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“It’s been a matter of some debate for a very long time if one of these tissue layers controls plant growth or if all three layers have to work together,” Chory said. “Our paper shows very clearly that the epidermis is in control—in both driving and restricting growth. In addition, our studies show that the cells in the epidermis “talk” to the cells in the inner layers, communicating that they too should expand.”