Hybrid rice refers to the selection of two rice varieties with certain genetic differences, and their excellent characters can complement each other, thus producing the first generation hybrid with heterosis for production, which is hybrid rice. Heterosis is a common phenomenon in biology, and using heterosis to improve crop yield and quality is one of the main achievements of modern agricultural science.

Heterosis is a common phenomenon in biology. Using heterosis to improve crop yield and quality is one of the main achievements of modern agricultural science. Two rice varieties with certain genetic differences and complementary excellent characters are selected to cross to produce a hybrid with heterosis, that is, hybrid rice.

Rice has obvious heterosis, which is mainly manifested in vigorous growth, developed roots, large panicles and many grains, and strong stress resistance. Therefore, it has always been a breeder's dream to greatly increase rice yield by using rice heterosis. However, rice is a self-pollinating plant, and both pistils and stamens are planted in the same spikelet. Because the spikelet is very small, and each flower bears only one seed, it is difficult to produce a large number of hybrid seeds by artificial emasculation, so the heterosis of rice has not been applied for a long time.