Suberin Plays Vital Role in Plant Nutrient Absorption

Suberin is a waxy substance found between some plant cells. It primarily prevents water from penetrating tissues. But there's more to suberin than meets the eye. Scientists from Purdue University, by studying a mutant Arabidopsis plant that produces twice as much suberin as normal varieties, believe that manipulating the substance may lead to plants that better absorb nutrients. Their work appears in the current issue of PLoS Genetics.

David Salt and colleagues discovered which pathways particular nutrients use to get into plant shoots based on suberin concentration. By adjusting the amount of suberin in roots, plants could be engineered to allow for easier absorption of beneficial nutrients. Plants with more suberin were found to contain less calcium, manganese and zinc, and high sodium, sulfur and selenium in their leaves. "Just like animals, plants want to select the things they take in," Salt said. "They want a certain amount of potassium or a certain amount of nitrogen." The amount of suberin they produce allows them to choose how much they get.

Salt and colleagues also observed that plants with twice the amount of the waxy substance activated a defense mechanism to keep from wilting. Since suberin was restricting water absorption, the plant allowed less transpiration, or evaporation of water from the leaves. Manipulation of suberin might also lead to the development of plants that use water more efficiently.

The scientific paper is available at http://dx.doi.org/10.1371/journal.pgen.1000492 For more information, visit http://news.uns.purdue.edu/x/2009a/090522SaltSuberin.html