Why is super rice so high-yielding? Yuan Longping speaks with full confidence about the achievements of hybrid rice
Recently, the hundred-mu demonstration project of the new two-line hybrid rice combination "Chaoyou Qianhao" carried out at the base in Haitang District, Sanya City, Hainan Province, achieved an average yield of 941.79 kg per mu after on-site expert verification, setting the highest rice record in Hainan, China.
Regarding this verification result for China's fifth-phase super rice, the project leader, Academician of the Chinese Academy of Engineering Yuan Longping, was "satisfied but not content." He said: "'Higher yields and still higher yields' is the eternal theme of breeding."
As for the controversy previously triggered by large-scale yield reductions of "Liangyou 0293" in Anhui, Yuan Longping believes that increasing grain production requires not only good seed but also good fields, good methods and good conditions. If the field is poor, it is difficult to achieve high yields with good seed alone. He said that good fields are the foundation, just as building a tall building requires laying a solid foundation first; the taller the building, the firmer the foundation must be. If the state increases efforts to improve low- and medium-yield fields, super rice yields will rise further.
Single-mindedly pursuing high yields
In May, Sanya's temperature reaches over 30 degrees. Yuan Longping arrived in Sanya from Beijing, and after getting off the plane he took a car to the Haitang base to inspect the "Chaoyou Qianhao" rice and guide the scientific and technical personnel in preparing for the next day's verification work.
"Chaoyou Qianhao" is a new strongly heterotic super hybrid rice combination bred over many years by the scientific research team led by Yuan Longping. It not only has high yield but also excellent quality. In order to better understand its traits and speed up its promotion, this year the China National Hybrid Rice Research and Development Center set up 62 hundred-mu demonstration plots in 46 counties (cities) across the country. Sanya, as China's southern breeding base for rice, has two demonstration bases, and the Haitang base is one of them.
Yuan Longping was very optimistic about the display of "Chaoyou Qianhao" in Sanya. Since sowing on December 17 last year, he spent basically the whole winter in Sanya. In April this year, he also presided over a super rice on-site observation meeting in Sanya, inviting more than 40 super rice experts from 17 provinces and cities across the country to visit, in order to advance the hundred-mu demonstration of "Chaoyou Qianhao" in Sanya and the inland areas.
On the day of verification, Yuan Longping appeared on site again. At 4 p.m., after the harvested rice was dried, the grain moisture was measured, and he only left satisfied after experts repeatedly calculated and obtained accurate verification results.
Before leaving, he said that the rice growth period in Sanya is more than 10 days shorter than in the inland areas, the plant height is 10 cm shorter, and there is one fewer leaf. "It seems that 'Chaoyou Qianhao' has more advantages in inland provinces, and achieving the demonstration planting target of 16 tons per hectare looks promising!"
The achievements of hybrid rice are evident to all
Yuan Longping, long past his eighties, why is he still so persistent about super rice breeding? "The country needs me, the people need me. As long as my health permits, I will continue climbing on the road of super rice innovation." This was his answer.
Previously, because large-scale yield reductions of "Liangyou 0293" in Anhui triggered various doubts and controversies among netizens about super rice, but Yuan Longping believes that super hybrid rice cannot be denied just because an individual variety has problems. The achievements of China's hybrid rice research are evident to all.
Japan was the first country in the world to carry out super rice research. Over 34 years, its 27 million mu of high-quality rice fields have averaged 450 kg per mu. In 2014, China had 440 million mu of rice, of which 250 million mu was hybrid rice, with an average yield of 451 kg per mu. Yuan Longping believes that this is already a fairly good level, because 70% of China's fields are low- and medium-yield fields, which shows that super rice has played an important role.
The now-retired senior agronomist Feng Keshan once discovered a wild rice male sterile plant in 1970, making an important contribution to the successful breeding of three-line hybrid rice in 1973. He told reporters about the hardships back then of working day and night under Yuan Longping's leadership on hybrid rice breeding. "The successful breeding of three-line hybrid rice was the result of more than 30 research units in more than 10 provinces and cities across the country using thousands of varieties to conduct tens of thousands of crossbreeding experiments with 'Yebai.'"
The International Rice Research Institute began super rice research in 1989 and planned to achieve 12-12.5 tons per hectare by 2000; however, this target has still not been achieved to this day. In 2005, Australia ranked first in the world in rice yield per mu, with an average of only 10 tons per hectare, that is, 670 kg per mu, while India had only 200 kg, and Thailand less than 200 kg.
China's rice yield per unit area is already leading internationally. Yuan Longping said that if the demonstration yield of super rice reaches 1000 kg per mu, then with a 30% discount for large-scale promotion it would be 700 kg, that is, 10.5 tons per hectare. If low- and medium-yield fields reach 700 kg per mu, that would be a remarkable leap.
Viewing super rice objectively
Regarding the previous online criticism of super rice, experts believe that many views are highly one-sided and fail to look at the issue objectively, fairly and scientifically. "The role of hybrid rice in advancing China's rice production increase and safeguarding national food security is beyond doubt," said Zhou Zhikui, director of the Hunan Provincial Seed Bureau. In recent years, Hunan's super rice breeding level has risen rapidly, with both yield and quality improving."
In recent years, China's super rice research has achieved very good results, but the resistance of seeds will vary when planted in different regions, and as time passes and pathogens change, their effect will also change. Wang Feng, a researcher and director of the Rice Research Institute of the Guangdong Academy of Agricultural Sciences, said that super rice cannot be completely written off just because a small problem has arisen.
So, how should the gap between super rice demonstration yields and farmers' actual planting yields be viewed? In this regard, experts believe that demonstration high yields depend not only on the seed factor but also on good fields and good cultivation management. At present, most of China's rice fields are low- and medium-yield fields, and when planted on a large scale of several million or tens of millions of mu, it is difficult to reach the yields of demonstration plots.
"Most of the people farming in rural China today are elderly, and it is very difficult for them to master and make good use of modern planting and management techniques. In addition, income from grain farming is relatively low, and farming households are not very willing to put much effort into management. This is also an important reason for the gap." Wang Feng said.
"Ordinary people do not understand scientific farming, which is understandable. As mass media that spread science, reports should not only value facts but also explain science; otherwise they will mislead readers," said Deng Guofu, a researcher and vice president of the Guangxi Academy of Agricultural Sciences.