URI researchers help identify gene that determines sex in flowering plants

Discovery may be key to boosting crop output

Posted on
Posing in their URI lab are (l-r) Albert Kausch, John Mottinger, Kimberly Nelson and Joel Hague. (Photo by Nora Lewis.)

KINGSTON, R.I. – November 21, 2016 – A team of scientists from the University of Rhode Island joined colleagues from Yale University and the Max Planck Institute in the discovery of a gene that controls sex determination in plants. The discovery could open the door to the creation of highly productive hybrid seeds for many agricultural crops.

“Controlling sex determination in plants is essential to making hybrid plants,” said Albert Kausch, URI professor of cell and molecular biology, who led the URI team along with Professor Emeritus John Mottinger. “Hybrid crop plants are healthier and increase yields per acre. As world population increases, we’re going to need to double our food production in the next 50 years, and hybrid plant production is one way we can do that.”

Joining Kausch and Mottinger on the URI team were Kimberly Nelson, coordinator of the Plant Biotechnology Lab, and Research Associate Joel Hague. Mottinger contributed 15 years of genetic research to the project.

Their research was published last month in the journal Science Advances.

According to Kausch, most crop plants have both male and female parts in the same flower, making it difficult and expensive to create hybrids. In corn, however, hybrid production is simple because the male and female parts are already separated – the ear is female and the tassel is male.

“If we could separate them in wheat or rice or sorghum, then we could increase the amount of grain we produce per acre,” he said. “It took many years of effort to figure it out, but now we can.”

The researchers isolated a key gene in maize, which they called silkless 1. When expressed in plants, this gene programs flowers to become female. Seeds produced on these female plants are hybrids.

The role of the URI team was to identify and analyze the genes in wild-type and transgenic plants.

“That’s one of our specialties – we know how to put genes into corn and other plants,” Kausch said. “It’s one thing to identify the gene, but it’s another to know that it’s functioning. Together with the Yale group, we analyzed how the gene worked by putting it back into the plant and showing that it causes female development.”

Beyond the practical applications of this discovery, Kausch said the basic biology of the project was unexpected.

“The gene that codes for sex determination was surprising to us,” he said. “I would not have thought that particular gene would cause female development. But when we looked at it closely, it was the one.”

The URI professor called the discovery “an important contribution to agriculture, a significant achievement to increasing world food production.” The next step, he said, would be to apply this gene to the development of new hybrid plants.

Primary funding for the research was provided by the National Science Foundation and the Bill & Melinda Gates Foundation.