PXY and CLE are two genes that control outward growth in the tree trunk, according to the researchers. They discovered that by manipulating these genes in poplar trees to over-express them, they could get the trees to grow twice as fast as they normally would. Poplars of a certain age grew taller, wider, and had more leaves as a result. The researchers write, “Our findings show that the PXY-CLE pathway has evolved to regulate secondary growth, and that manipulating this pathway can result in dramatically increased tree growth and productivity.”
Fast-growing trees can be useful in a variety of situations. For starters, researchers may be able to use them as a plentiful source of renewable biofuels. They could also be used to create high-yield plantations that produce the same amount of timber or pulp on half the land. More broadly, scientists may be able to learn more about how plants respond to various climate-related challenges as a result of this discovery.