The root of the matter: Drought tolerance in plants – Texas Farm Bureau

By Jennifer WhitlockField Editor

The roots of plants may hold the key to improving drought tolerance, according to researchers at the University of California (UC).

For a decade, these university scientists have been creating an mRNA atlas of tomato plant roots, because the roots are where plants first detect drought and other environmental threats.

Thats where they found several sets of genes that protect plants from stressors, according to an article published in the research journal Cell.

The genes the researchers targeted are responsible for three key parts of plant anatomy: xylem, suberin or lignin and meristems.

Xylem are vascular tissues, similar to vessels, which transport water and nutrients from a plants roots to stems and leaves. They are also involved in creating the structural basis that keep stems and trunks upright.

Xylem are very important to shore up plants against drought, as well as salt and other stresses, Siobhan Brady, lead study author and a plant biology professor at UC Davis, said.

Although some genes responsible for xylem formation were already known, Brady and the other researchers found new genes involved in the process.

Another discovery was made in the genes that direct outer layers of roots to make lignin and suberin.

Suberin surrounds plant cells and holds in water during dry periods. Julia Bailey-Serres, UC Riverside professor of Genetics, said tomato and rice plants have suberin in their roots, while suberin surrounds the outer cells of apples to keep the fruit water-tight.

Suberin and lignin are natural forms of drought protection, and now that the genes that encode for them in this very specific layer of cells have been identified, these compounds can be enhanced, she said. Im excited weve learned so much about the genes regulating this moisture barrier layer. It is so important for being able to improve drought tolerance for crops.

Similarities in meristem genes were identified across Arabidopsis, a common model plant, and tomato and rice plants. The discovery is important because the meristem, the growing tip of a root, is the source of all root cells.

Its the region thats going to make the rest of the root, and serves as its stem cell niche, Bailey-Serres said. It dictates the properties of the roots themselves, such as how big they get. Having knowledge of it can help us develop better root systems.

Although the researchers only analyzed three plants, they believe the results may be applied to a wider spectrum of plant varieties.

Tomato and rice are separated by more than 125 million years of evolution, yet we still see similarities between the genes that control key characteristics, Bailey-Serres said. Its likely these similarities hold true for other crops too.

View original post here:

The root of the matter: Drought tolerance in plants - Texas Farm Bureau