The taro plant, used to make poi, is a sacred ancestor of the Hawaiian people that can't be owned, protesters said yesterday.

Activists and farmers urged the University of Hawai'i to give up three of its patents on varieties of taro genetically enhanced by crossbreeding. About 20 people rallied in a small field of taro growing on the university's Manoa campus.

"The taro is our ancestor. It's not a commodity," said longtime Hawaiian activist Walter Ritte. "The University of Hawai'i cannot own our ancestors. They're setting the precedent for the rest of the world to come here and start patenting things."

According to Hawaiian belief, the cosmic first couple gave birth to a stillborn, Haloa, from whose gnarled body sprang the broad-leafed plant whose bulb-like corms are ground into one of Hawai'i's best-known foods. The Hawaiian people, it is believed, came from a second brother, making the plant part of their common ancestry.

The three lines of taro patented by the University of Hawai'i share a lineage that dates to the Polynesian taro first brought to the Islands centuries ago, Ritte said. Since the fourth or fifth century, taro has been crossbred thousands of times by Hawaiian farmers to create new strains of the plant.

"The idea that one generation of people could claim ownership of something that's much older than we are is ridiculous," said David Strauch, a taro farmer who grows traditional varieties on O'ahu. "Taro is so central to Hawaiian culture."

A spokeswoman for the college where the scientists did their work on taro said their varieties of taro are distinct from those found naturally.

These three types of taro are more resistant to leaf blight and root rot, and they grow bigger than wild varieties, according to the 2002 patent applications.

"They took something that wasn't working 100 percent, and they basically came out with a new variety," said Ania Wieczorek, spokeswoman for the College of Tropical Agriculture and Human Resources. "This isn't just something found in the wild. They took something and made it much better."

Ritte claimed in a letter to the dean of the college that patents should not have been granted for these genetically enhanced plants. He wrote that the patents were given in 2002 based on preliminary observations that have not been confirmed by controlled experiments.

The patents require farmers who use these varieties to pay licensing fees to the university and to let officials onto their property to study the plants. Farmers may not sell the seeds.

It would be up to the scientists who own the patents to revoke them, Wieczorek said.

Ritte said that if they do not give up these taro patents, he plans to take legal action before the U.S. Patent and Trademark Office.

Ritte has gone to battle with the university before over the genetic modification of taro. As a result, the university agreed in May to stop experiments on Hawaiian varieties of taro because of cultural concerns that it was tampering with native species.