The third-generation breeding method for hybrid rice is being developed by Yuan Longping's team

Xinhua News Agency, Changsha, December 14 (Report) Yuan Longping recently revealed that the Hunan Hybrid Rice Research Center is actively researching a third-generation breeding method. Because it combines the advantages of the previous two generations, this means it may be possible to breed hybrid rice with higher yields, better quality and stronger resistance.

The first generation of hybrid rice adopted the "three-line method," in which a hybrid first generation is formed through a male sterile line, a maintainer line and a restorer line. This method has a complicated procedure, many seed production steps and high costs, and the probability of selecting an excellent combination is relatively low. It is also difficult to resolve the contradiction between high yield and good quality in hybrid rice. The second-generation breeding method is the "two-line method," which uses male sterile lines and restorer lines for hybridization to achieve free combination, and the probability of breeding excellent varieties is much higher than with the three-line method. At present, hybrid rice breeding in China generally adopts the second-generation method, and varieties combining quantity and quality have already been bred, represented by Y Liangyou 900, whose yield per mu exceeded 1000 kg and whose grain quality reached the national second-grade high-quality rice standard.

"But the second-generation breeding method also has certain shortcomings." Zhang Yuzhu, deputy director of the Hunan Hybrid Rice Research Center, explained that two-line method breeding is easily affected by temperature, and the risk in seed production is relatively high. This usually causes huge losses to seed companies, and if it cannot be identified, it will also affect farmers' production.

Yuan Longping explained that China's third-generation hybrid rice uses an engineered male sterile line as a genetic tool, and has the advantages of both the stable fertility of the "three-line method" and the free combination of the "two-line method." Its biggest feature is that the female parent is not affected by the environment, seed production is safe, and combination is free, making it possible to breed more excellent varieties.

"In areas with many people and little land, high yield is mainly the breeding goal, and high-yield genes can be selected for combination. For areas susceptible to rice blast, disease-resistance genes can be introduced to continuously improve disease resistance. To breed hybrid rice with better comprehensive traits such as higher yield, better quality and stronger resistance, high-yield, high-quality, highly resistant and broadly adaptable genes can be optimized and combined, bringing hybrid rice to a new level in both quantity and quality." Zhang Yuzhu said. (Reporter Zhou Mian)