For many in China, the term “genetically modified food” evokes nightmares: poisoned seeds, contaminated fields, apocryphal images of eight-legged chickens.

China and the global agricultural industry are betting billions of dollars that they can change those perceptions. They are starting with farmers like Li Kaishun.

Mr. Li is an agricultural thought leader. The 39-year-old millet, corn and peanut farmer in China’s eastern Shandong Province quickly adopts new techniques to bolster production, such as mixing pesticides with his seeds before he plants them as a way to reduce overall pesticide use. He rents land from local farmers, giving him 100 acres in a country where the average farm takes up only one-quarter of an acre.

The next innovation he wants: genetically modified crops. That view appeals to DuPont, the American seed giant, which offers Mr. Li and his family discounts on seed, pesticides and fertilizers to cultivate those views.

One thing DuPont cannot provide — though it hopes to someday — is genetically modified seeds themselves. In China, genetically modified crops are largely banned from food destined for dinner tables.

“If there is better seed and better technology, I would definitely want it,” Mr. Li said. “But I have never seen a G.M.O. seed. Neither have I heard about anyone planting one.”

China has ambitions to be a major player in genetically modified food. One of its state-run companies is vying to acquire Syngenta, the Swiss agricultural company, for $43 billion, which would make it China’s largest foreign purchase ever. It is ramping up spending on research and development and supporting a nascent homegrown industry that it hopes can someday become China’s answer to Monsanto and DuPont. In a 2013 speech, Xi Jinping, the country’s president, told his audience, “We can’t let big foreign companies dominate our G.M.O. crops market.”

Many Chinese officials see G.M.O. science as a way to bolster production in a country where large-scale farming is still uncommon — a legacy of the Communist Revolution, when land was stripped from landlords and given to peasants. China also hopes to better feed its growing and increasingly affluent population on its own.

But even if China succeeds in building a vibrant industry, it has to persuade a frightened public that genetically modified food is not another Chinese food scandal in waiting.

“I’m cautiously optimistic that will happen, but it’s still a significant challenge to address public perception of G.M. food,” said William S. Niebur, chief executive of Origin Agritech, a Chinese genetically modified seed developer and a partner with DuPont. He says that the public wants transparency, accessible information and choice, but “where we are today, the emotions continue to be stronger than facts.”

In a country where dissent is roundly discouraged, a number of activists have publicly criticized the pending Syngenta deal. Hundreds of citizens, including Qin Zhongda, a 93-year-old former minister for China’s chemical industry, signed letters to top leaders and the China National Chemical Corporation, Syngenta’s would-be buyer, saying that the Syngenta deal would lead to uncontrollable pollution of China’s food crops. They also predicted severe damage to the health of Chinese consumers, the safety of the country’s food supply and the livelihoods of Chinese farmers.

“ChemChina must stop this suicidal acquisition that will destroy the country,” one letter said.

G.M.O. food has come under further scrutiny in recent weeks after state media reported that a testing center for modified animals at the Chinese Academy of Agricultural Sciences had faked inspection records and let unqualified people perform tests. The Ministry of Agriculture conducted an investigation into the academy after a former Ph.D. student made claims online last month about problems there.

A spate of reports on illegally planted seeds prompted Lin Xiangmin, an official in charge of safety management and intellectual property rights of G.M.O.s at the Ministry of Agriculture, to tell The Beijing Times newspaper that the department was working to make illegal planting of G.M.O. seeds a criminal offense.

For many opponents, China simply is not ready. “Safety can be achieved only with regulation,” said Cui Yongyuan, an anti-G.M.O. campaigner at the Communications University of China. “Many Chinese scientists don’t seem to understand this. They feel that safety is created in a laboratory.”

The roots of this skepticism run deep. Human tampering with food has been behind many of China’s most shocking food scandals. The tainted milk that killed six babies and injured hundreds of thousands of others stemmed from milk producers’ adding a chemical to make the milk look protein-rich. Fruit has been spiked with chemicals to make it look fresh and to stimulate growth.

Those fears, combined with China’s voluble online community, can sometimes lead to rumors. Last year, KFC, the fried-chicken chain popular in China, sued three Chinese internet companies over online accusations that it used genetically modified chickens with six wings and eight legs to feed its customers.

“One of the steps the research community has been doing is trying to extend the knowledge about the G.M.O.s to the public,” says Cao Cong, a professor at the University of Nottingham in China and the author of the forthcoming book “Genetically Modified China,” “but the public still doesn’t want to accept this kind of knowledge.”

Further complicating matters, China already grows and buys plenty of genetically modified crops — just, generally, not for people. Chinese farmers grow genetically modified cotton, and meat and dairy companies buy genetically modified corn from abroad to feed pigs and cattle. G.M.O. seeds are allowed for growing papayas.

That has led to accusations that G.M.O. crops have already crept into Chinese fields. In January, the environmental group Greenpeace said it found that domestic corn crops in northeastern China contained genetically modified material. Chinese officials said they had ramped up inspections.

Unapproved G.M.O. food can be found elsewhere in China’s food supply, said Jiajun Dale Wen, an energy and environment researcher at Renmin University. For example, many papaya seeds planted in China’s southern island of Hainan are not the kind approved by the government, while genetically modified rice can be found in some fields, she said.

“In theory, China should have a supervision of G.M.O.s that is stricter than the U.S.,” Ms. Wen said. “The Ministry of Agriculture has said that they would punish every case they found. But in reality, the punishment is light.”

Many farmers remain outright opposed to using G.M.O. seeds, or just apathetic.

“The seed, pesticide and fertilizer market is kind of in a mess,” said Shi Guangzhi, a 44-year-old farmer with about 180 acres planted in corn in Bayan County, in China’s northern Heilongjiang Province.

“We don’t have the abilities to tell what is good and what is bad,” he said. “I can only learn from word of mouth which seed does well this year. Then everyone will plant this seed next year.”

Mr. Shi has little time to dream about the G.M.O. future that the government has planned. “I heard that the government doesn’t allow the growth of G.M.O. seeds. Then it will be difficult for me to sell it.”

That makes farmers like Li Kaishun, in Shandong Province, valuable to G.M.O. proponents. Although he says he does not know much yet about genetically modified seeds, he is willing to learn.

“What is G.M.O.?” he asked reporters for The New York Times. “If you say G.M.O. seed is good, can you provide me some?”