After graduating in 1953, Mr. Yuan took a job as a teacher in an agricultural college in Hunan Province, keeping up his interest in crop genetics. His commitment to the field took on greater urgency from the late 1950s, when Mao’s so-called Great Leap Forward — his frenzied effort to collectivize agriculture and jump-start steel production — plunged China into the worst famine of modern times, killing tens of millions. Mr. Yuan said he saw the bodies of at least five people who had died of starvation by the roadside or in fields.
“Famished, you would eat whatever there was to eat, even grass roots and tree bark,” Mr. Yuan recalled in his memoir. “At that time I became even more determined to solve the problem of how to increase food production so that ordinary people would not starve.”
Mr. Yuan soon settled on researching rice, the staple food for many Chinese people, searching for hybrid varieties that could boost yields and traveling to Beijing to immerse himself in scientific journals that were unavailable in his small college. He plowed on with his research even as the Cultural Revolution threw China into deadly political infighting.
In recent decades, the Communist Party came to celebrate Mr. Yuan as a model scientist: patriotic, dedicated to solving practical problems, and relentlessly hard-working even in old age. At 77, he even carried the Olympic torch near Changsha for a segment of its route to the Beijing Olympics in 2008.
Unusually for such a prominent figure, though, Mr. Yuan never joined the Chinese Communist Party. “I don’t understand politics,” he told a Chinese magazine in 2013.
Even so, the Xinhua state news agency honored him this weekend as a “comrade,” and his death brought an outpouring of public mourning in China. In 2019, he was one of eight Chinese individuals awarded the Medal of the Republic, China’s highest official honor, by Xi Jinping, the national leader.
Mr. Yuan is survived by his wife of 57 years, Deng Zhe, as well as three sons. His funeral, scheduled for Monday morning in Changsha, is likely to bring a new burst of official condolences.