Giving Tomatoes New DNA Now Takes Less Time by Patricia Waldron-Cornell

Scientists have cut the time required to modify tomato genes by six weeks.

While looking for ways to make tomatoes and other crop plants more productive, researchers developed a better method for “transforming” a tomato—a process that involves inserting DNA into the tomato genome and growing a new plant.

By adding the plant hormone auxin to the medium that supports growth of tomato cells, they can speed up the plant’s growth, ultimately accelerating the pace of their research. They describe this advance in the journal Plant Cell, Tissue and Organ Culture.

Tomatoes
Image source: Wikimedia Commons
Tomatoes

Typically, transformation works by using a soil bacterium called Agrobacterium tumefaciens to insert a new segment of DNA into the cells of tomato seedling tissues. The transformed cells are transplanted onto plant regeneration medium, which contains nutrients and hormones that cause the tissue to grow into a tiny new plant. These plantlets are then transferred to root induction medium where they grow roots, before being planted in soil and hardened in the greenhouse.

Wild tomato ‘hair’ holds defense secrets

In the new method, the researchers add auxin to the regeneration and rooting media. The addition reduces the length of the procedure from 17 weeks to just 11.

“If you can speed up the plant development, which is what the auxin is doing, you can decrease the time it takes to get genetically engineered lines,” says Joyce Van Eck, assistant professor at Cornell University’s Boyce Thompson Institute. Van Eck worked with former postdoctoral scientist Sarika Gupta.

Researchers in the Van Eck lab perform tomato transformations routinely, as a research method to understand how individual genes affect tomato growth and development. Their new protocol not only saves time, but also uses fewer materials, and saves money. The researchers can then finish experiments sooner and potentially run more projects at once.

The project came out of collaboration with Cold Spring Harbor Laboratory to identify gene pathways that could be used to breed crops with higher yields.

“We’re looking at the genes and gene networks involved in stem cell proliferation, meristem development and flowering and branching,” says Van Eck, “with the end goal being that maybe genes that we identify in tomato, which is strictly being used as a model, might help us understand what can be done to increase yield in other crops.”

Source: Cornell University

Original Study DOI: 10.1007/s11240-016-1063-9