In the 1960s, China experienced natural disasters that ravaged crops across the country, causing widespread famine. These unfortunate events inspired agricultural scientist Yuan Longping to research and develop hybrid rice. Hybrid crops offer more benefits than naturally occurring ones; successful hybrid crops feature beneficial traits from both parent crops, and are better crops than either of the parents. For example, if one parent is high-yield but vulnerable during droughts while another is drought-resistant but low-yield, they can produce a hybrid that is both high-yield and drought-resistant.

Yuan understood the benefits of hybrid rice and realized that growing hybrid rice could be a great boon to the nation. Better rice crops would mean higher production and more access for the masses. Today, over half of China's rice-growing land area is planted with rice hybrids, and China is by far the largest hybrid rice producer in the world. As rice is a staple for Chinese people, hybrid rice has become an integral part of the country's agricultural industry and accounts for a large portion of the 500 million tons of annual grain output needed to feed the population.

Though hybrid rice was first developed in 1966 by American plant breeder Henry Beachell, Yuan was the first to release hybrid rice varieties for public consumption. Yuan is known as the "father of hybrid rice" in China. He released the first variety in 1974 after years of research and development.

Rice is generally a self-pollinated plant that produces its own pollen, which in turn falls into the crop's ovary and fertilizes it to produce seeds – these seeds are known as grains of rice. Therefore, in order to develop hybrid rice, breeders need to find a rice crop that is sterile to cross with a fertile crop. Originally, it was believed that scientists would have to sterilize crops in order to do this, but in 1970, Chinese scientists discovered a naturally-occurring male sterile rice plant on Hainan Island.

Chinese agricultural scientists experimented and crossed this male sterile rice crop with other rice crops to see if they could reproduce this trait of sterility. The resulting sterile plants were repeatedly crossed until the scientists had a stable sterile parent rice plant – this was called the CMS line of rice crops. More CMS plants were produced by crossing with another genetically identical plant that was fertile, called the maintainer line. The CMS plant was crossed with a fertile plant, also known as the restorer line, and the resulting seeds became the first hybrid seeds for release. Farmers then planted these seeds to grow hybrid rice crops which yielded more rice than most naturally occurring crops. Today, all countries developing hybrid rice still use the CMS, maintainer and restorer system.

Despite its benefits, hybrid rice also has drawbacks. It can be difficult to find CMS lines, and maintainer and restorer lines appropriate for these CMS lines. Developing hybrid rice is different for each climate and environment. Dr. Raafat El-Namaky of the Africa Rice Center (AfricaRice) said this has proven to be a challenge. "We have to develop special hybrids for each ecology," he said. "Of course, sometimes we can find some hybrids with high adaptability under different ecologies but this maybe only a few hybrid combinations. Each region is different with different biotic and abiotic stresses, and consumer preferences are different." Also, the seeds of hybrid rice crops cannot be re-used, as the vigor of the original hybrid crop weakens after the first generation.

But in China, the benefits have outweighed the negative aspects of hybrid rice. Yuan is still hard at work, constantly improving hybrid rice crops and increasing the yield. As of last September, scientists raised the yield of hybrid rice to 926.6 kg per mu (0.067 hectares) and believe the goal of a 1,000 kg per mu yield is in the near future.

Many countries in Africa are taking cues from the success of hybrid rice in China, hoping to alleviate famine and poverty. One organization looking to breed hybrid rice that can succeed in African climates and arable conditions is El-Namaky's organization, AfricaRice. "Since 2010, Africa Rice Center initiated a breeding program to develop hybrid rice with high adaptability under African conditions," said El-Namaky. "They collaborate with China to test the adaptability of Chinese hybrids under African conditions. When we develop good hybrid combinations with high-yield potential, this will increase the rice production and help small farmers in Africa to produce sufficient food." Though hybrid rice development is still very much in a trial-and-error phase, organizations like AfricaRice have received support from the international community and have a bright future.

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