Relay "Dream of Coolness under Woxia"

  Agricultural workers diligently seek how "Oriental Magic Rice" can better contribute "grain" to food security

  Our reporters Liu Ziling, Zhou Mian, Liu Fangzhou, Zhang Ge

  Due to complex factors such as the continuation of the new crown epidemic, the intensification of geopolitical conflicts, and the frequent occurrence of natural disasters, the global food supply is facing huge uncertainty. Some countries and regions have begun to restrict their food exports out of food security considerations, which has further triggered the global food crisis. worry.

  May 22 is the first anniversary of the death of Academician Yuan Longping, the "Father of Hybrid Rice".

"Developing hybrid rice to benefit the people of the world" is Yuan Longping's lifelong pursuit and dream.

Since going abroad for the first time in 1979, Chinese hybrid rice, known as the "Oriental Magic Rice", has been researched and promoted in dozens of countries and regions, making significant contributions to world food security.

  Food security is the most important thing in a country.

In the current world context, it also highlights the importance of my country's "holding the rice bowl firmly in its own hands".

As the country's major grain producing area and the "base camp" of hybrid rice, Hunan Province has strong agricultural modernization technology and seed scientific research strength. How can we better contribute "grain" policies for national and world food security?

Scientific researchers have been tirelessly exploring and pursuing...

  The third generation hybrid: let rice "marriage freedom"

  The third-generation hybrid rice, regarded by Yuan Longping as the key to breaking through the "ceiling" of 1,200 kilograms per mu in a single season, was first publicly tested in October 2019, although this time the "three-generation hybrid rice" that appeared in Qingzhu Village, Hengnan County, Hengyang City, Hunan Province this time. "Excellent No. 1", "only" achieved a result of 1046.3 kg, but in the eyes of the industry, it has great potential, and, in addition to high yield, it has more new features suitable for large-scale planting by ordinary farmers.

  "With the technology we currently have, it is not difficult for the third-generation hybrid rice to reach 1,200 kilograms or even 1,300 kilograms per mu in a single season," said Zhao Bingran, deputy director of the State Key Laboratory of Hybrid Rice and an expert at the Hunan Hybrid Rice Research Center.

  "The third-generation technology uses genetically engineered male sterile lines as a genetic tool. It can be said that it enables hybrid rice to achieve true 'marriage freedom'." Li Xinqi, a researcher at Hunan Hybrid Rice Research Center, used a special metaphor. to explain:

  Using the first-generation technology to cultivate an excellent new hybrid rice variety, it seems that among thousands of rice materials, only A and B are suitable for "marriage", and B is still hidden in the "broad rice sea". To meet, not only requires a lot of energy, but also requires a lot of luck.

In the second generation of technology, A can "marriage" with all other rice. Although the selection surface is greatly improved, it cannot guarantee stable production of offspring.

The third-generation technology is no longer just for A. It allows all rice plants to theoretically find their "other half" and produce excellent offspring.

  Yuan Longping has stated on many occasions that the third-generation hybrid rice not only has the advantages of stable fertility of the three-line sterile line and free combination of the two-line sterile line, but also overcomes the limitation of the three-line sterile line for the combination of two lines. The sterile line may have the disadvantages of failure of seed production and low reproductive yield due to weather. It is stable and sterile in any area at any time, and seed production and propagation are very simple.

  If measured by the standard of ordinary people, the first two generations of hybrid rice are more dependent on large, fat and water, and have higher requirements on the ecological environment and planting technology. Ordinary farmers cannot easily control the high yield obtained by "expert farming". The experimental field moves to the production field.

  The third generation of hybrid rice overcomes these deficiencies.

Gan Zongheng, a cadre of the Agriculture and Rural Bureau of Hengnan County and the project leader of the Qingzhu Village Base, introduced that the local planting environment in Qingzhu Village is not special, with an altitude of less than 100 meters. Field management or pest control, the technology used and the energy invested are not much different from the normal planting of ordinary farmers.

  "It can be said that it is exactly the same as my previous farming." The local farmer Chen Taijia is an "old-fashioned" who has grown rice for more than ten years.

He said that taking fertilization as an example, the common nitrogen, phosphorus and potassium fertilizers are applied, and the "food intake" is about 40 kilograms per mu of ordinary rice. Tillering, flowering and grain filling do not require special care at different critical periods of rice growth.

  Unlike in 2019 with single-cropping late rice "taking the test", in November 2020, in the same place, "Sanyou No. 1" created the third generation of hybrid rice with a double-cropping late rice yield of 1530.76 kg per mu with the "identity" of double-cropping late rice 's record.

And just one year later, still in the same place, the record was raised to 1603.9kg.

  Ordinary people may ask this question: Academician Yuan Longping's hybrid rice yield per mu has already exceeded 1,000 kilograms in one season, so wouldn't it exceed 2,000 kilograms after two seasons?

Why do we still need to tackle the problem of producing 1,500 kg per mu in two seasons?

  "First of all, the varieties with a per-mu yield exceeding 1,000 kilograms are all single-cropping rice, also known as middle-season rice. From the general practice and cultivation model of rice-producing areas in my country, it is impossible to grow double-cropping rice on the same piece of arable land once a single crop of rice is planted. ” Li Xinqi, an expert from the Hunan Provincial Hybrid Rice Research Center, said that the yield of middle rice is generally higher than that of early and late rice, but the yield of middle rice is not higher than the sum of early and late rice.

  In recent years, the state has attached great importance to expanding the planting area of ​​double-cropping rice.

"In the past, we used to say 'ton of grain fields', which meant that the yield per mu in two crops reached 1 ton. This has long been achieved in farmers' production fields, but 1.5 tons has never been achieved. Therefore, the results of these several yield tests It is of great significance to food security." Li Xinqi said.

  In addition to cultivating early rice varieties as soon as possible, researches on light and simplified cultivation of third-generation hybrid rice, weight loss and medicine reduction without reducing yield are all underway simultaneously.

Zhang Yuzhu, a veteran expert at the Hunan Hybrid Rice Research Center, said: "Only the higher we 'jump', the stronger the national food security will be."

  New low-cadmium varieties: seeking increase in polluted land

  Due to serious heavy metal pollution in soil, some areas of my country have been plagued by excessive cadmium content in rice for a long time, which not only seriously affects farmers' enthusiasm for growing grains, but also has a profound impact on national grain quality and safety.

  The first "National Soil Pollution Survey Bulletin" released in 2014 pointed out that the total excess of heavy metal content in my country's soil was 16.1%.

In terms of distribution, soil pollution in the south is more serious than that in the north, and soil pollution problems are more prominent in some regions such as the Yangtze River Delta, the Pearl River Delta, and the old industrial bases in Northeast China.

Among them, soil heavy metals in southwest and south-central regions have a larger range of exceeding the standard.

  Radical treatment of cadmium rice, soil treatment or seed treatment?

  In August last year, the Hunan Academy of Agricultural Sciences selected 160 mu of demonstration fields with soil cadmium content as high as 0.91 mg/kg in the Dongting Lake area to test new varieties of rice with low cadmium accumulation.

In order to compare the experimental results, the demonstration fields also planted common rice varieties at the same time period and with the same cultivation and management mode.

  Experts from Hunan Agricultural Society, Hunan Normal University, Institute of Subtropical Agroecology, Chinese Academy of Sciences and other units took samples on site and sent them to a third party for cadmium content testing. The test results were: the cadmium content of three low-cadmium varieties of rice was 0.032 mg/kg, 0.032 mg and 0.055 mg are far lower than the national standard of 0.2 mg per kilogram.

As for the common varieties tested and compared, the average cadmium content was 0.3 mg and 1.018 mg per kilogram.

  Many experts believe that because soil remediation must be artificially remediated through certain biological, physical or chemical means, which is not only costly and time-consuming, but also may bring potential risks such as secondary pollution and soil organic matter destruction. The promotion of planting is a safer and direct way to solve the problem of "cadmium rice".

  The low-cadmium rice varieties currently being tested are new cadmium-low-accumulation rice varieties bred using the cadmium low-accumulation molecular marker system. They were screened from global rice resources by the relevant team of the Hunan Academy of Agricultural Sciences.

In 2019, Hunan Academy of Agricultural Sciences unearthed two test materials that showed significantly low absorption of heavy metals in heavily cadmium-contaminated fields, and further established a low-cadmium molecular marker system, thus forming a set of rapid breeding of low-cadmium accumulation rice. method.

  According to Li Li, deputy director of the Hunan Hybrid Rice Research Center, the two materials screened in 2019 are the key to the significant progress of this experiment. They both lack the main gene for cadmium absorption, and were selected after crossing with existing varieties. New low cadmium variety.

"At present, the new varieties 'Xizi No. 1' and 'Xizi No. 2' have been cultivated to the fifth generation. It can be said that their low cadmium absorption is innate, and no special cultivation and management methods," Li Li said.

  In the demonstration fields, the cadmium low-accumulation rice cultivated by the physicochemical mutagenesis directional improvement technology will also receive on-site evaluation and technical appraisal.

"It also makes rice lose the main cadmium-absorbing gene. Physical and chemical mutagenesis uses technical means to 'knock out' the cadmium-absorbing gene in rice." Zhao Bingran said, "Previously, we used gene editing to directionally delete the cadmium-absorbing gene. However, because the gene editing technology is a transgenic technology, it is restricted by relevant national policies and cannot be promoted for cultivation, so the technical method of 'physical and chemical mutagenesis' is adopted."

  Different from the research method of Li Li's team, physical and chemical mutagenesis may lead to different genetic mutations. Therefore, Zhao Bingran's team finally screened out two mutations in cadmium-absorbing genes from 110,000 samples, and cultivated the first cadmium-absorbing gene at home and abroad. Low-accumulation hybrid medium sterile lines "Lian 1S" and "Shaoxiang 100".

  "These two technologies are not only developed by local teams in Hunan, but have also been tested and proven to have extremely high application value. Now that we have completed the previous work, we look forward to speeding up the approval process and simplifying procedures from the government and policy levels. Under the premise of allowing, we can open up green channels and promote the results on a large scale as soon as possible." Zhao Bingran said.

  Yin Wenhui, director of the Rural Division of the Hunan Provincial Department of Science and Technology, believes that the cultivation of low-cadmium rice varieties has found an operational way to solve heavy metal pollution, and has achieved a breakthrough in the technical path.

And it can be replicated and promoted on other crops according to the same technical path.

  Saline-tolerant rice: Rebuilding 100 million mu of fertile land

  There are about 1.5 billion mu of saline-alkali land in my country, of which about 340 million mu have the potential to be transformed.

In 2019, Yuan Longping put forward the 30-year goal of "realizing breakthroughs in breeding in the near future, improving technology integration in the mid-term, and realizing double improvement in production capacity and efficiency in the long-term".

According to the current industry design of 300 kilograms per mu, this means that 30 billion kilograms of grain can be produced "out of thin air" a year.

  The pace of research on saline-alkali-tolerant rice has accelerated significantly in recent years.

In 2017, a number of scientific research institutions and related enterprises including Hunan Hybrid Rice Research Center, Qingdao Sea Rice Research and Development Center, Guangdong Academy of Agricultural Sciences and China Rice Institute established the National Salt-Alkali-tolerant Rice Regional Test Consortium.

Subsequently, the consortium formulated the regional test standards for saline-alkali-tolerant rice, and conducted two national regional tests in succession.

In the tests conducted that year, a total of more than 10 varieties passed.

Of the 40 varieties in the three groups participating in the 2018 trial, 28 passed.

This number has also increased steadily in recent years.

  "A variety goes from a scientist's experimental field to a farmer's production field. It needs to go through preliminary tests, regional tests and production tests before it can be planted. The whole process is actually a process of selecting the best one after another." Li Xinqi told reporters that the regional test is one of them. The most critical "examination" directly determines the base number of saline-alkali-tolerant rice varieties that will be used for actual planting in my country in the future.

  In 2020, the 15-acre salt-and-alkali-tolerant pioneer variety "Chaoyou Qianhao" in Yazhou, Sanya, Hainan achieved an average yield of 508.4 kg per mu; in the Daqing demonstration base in Heilongjiang, the salt-alkali-tolerant rice variety "Suijing 18" was planted. The yield test results are equivalent to 460 kilograms per mu. The average yield per mu of saline-alkali-tolerant rice in the Xing'an League salt-tolerant rice test base in Inner Mongolia is 533.95 kg. The measured yield of 80 mu of sea rice tested in Yuepuhu County, Kashgar, Xinjiang is 549.63 kilograms per mu.

  In the same year, in cooperation with Hunan Hybrid Rice Research Center and Jiangsu Provincial Agricultural Technology Promotion Station, the pioneer combination of salt-tolerant rice "Chaoyou Qianhao" was tested in Fangling Reclamation Area of ​​Fangcha, Rudong County, Nantong, Jiangsu Province. The yield reached 802.9 kg, setting a new record for high yield of salt-tolerant rice.

  Academician Yuan Longping also proposed in 2020 to plant 100,000 mu of saline-alkali-tolerant rice, transform 1,000,000 mu of saline-alkali land, and reserve 10,000 mu of land that can be transformed. Demonstration of improvement and planting of rice in saline-alkali land, the demonstration planting area is five times that of the previous year.

  In March of this year, a more critical step was taken in the study of saline-alkali-tolerant rice: a national saline-alkali-tolerant rice research institute consisting of 11 units from 7 provinces (autonomous regions) of Hunan, Guangdong, Shandong, Xinjiang, Jiangsu, Hainan and Heilongjiang The Rice Technology Innovation Center was officially launched.

  Ai Zhiyong, Ph.D. of Hunan Hybrid Rice Research Center and Deputy Director of National Saline-tolerant Rice Technology Innovation Center, introduced that the center is headquartered in Sanya and has established three professional centers across the country. The advantages of relatively concentrated talents and enterprises, carry out the innovation of saline-alkali-tolerant rice seed industry; Haikou established a physiological regulation research center, focusing on the research and development of water and nutrient management of saline-alkali-tolerant rice, green planting and breeding and other technologies and related product research and development; Qingdao established saline-alkali land The improvement research center focuses on the chemical, physical, biological and engineering improvement technology research of saline-alkali land.

  At the same time, four regional sub-centers in South China, East China, Northwest China and Northeast China have been set up in typical saline-alkali land ecological zones in the country to undertake physiological regulation, variety creation, supporting technology research and demonstration and promotion of different ecological types of saline-alkali-tolerant rice. Inner Mongolia Xing'an League, Jilin Da'an, Shandong Dongying, Jiangsu Yancheng, Guangxi Beihai, Hainan Wenchang, Heilongjiang Zhaoyuan, Liaoning Panjin and other places set up the first batch of representative regional test stations, mainly to test new varieties of salt-tolerant rice and supporting new technologies Demonstration work.

  "Our goal is to cultivate 10 to 15 new varieties of rice with great application value suitable for planting in different saline-alkali land ecological zones by 2030, with a nationwide promotion area of ​​100 million mu and a yield of more than 300 kilograms per mu." Ai Zhiyong Say.

  "Five High" Super Rice: Latecomers Relay Tackling Key Problems

  In 1984, in Mapoling, the eastern suburb of Changsha, office buildings, laboratory buildings, and dormitory buildings rose from the ground, and the Hunan Hybrid Rice Research Center was established here.

Since then, it has become the "base camp" of my country's hybrid rice research: countless research projects have taken root here, each goal has been achieved here, and batches of scientific researchers have gained growth and progress.

  The breeding level of hybrid rice in my country has the strength to maintain the international leading position.

Behind this confidence, researchers and teams engaged in related research are inseparable.

Their rapid growth is closely related to Yuan Longping's support and trust in young people.

  "Academician Yuan Longping has not only made great contributions to the research of hybrid rice in my country, but also attached great importance to the development of talents." Wu Jun, deputy director of the State Key Laboratory of Hybrid Rice, introduced that when the center was first established, Yuan Longping sought scholarships and study abroad places from all over the world. A large number of young people are sent abroad for further study.

  "Hybrid rice research is a lofty undertaking that needs to be passed down from generation to generation." "Talents are the guarantee of a successful career." "Scientific research should not have a portal view, but should fully motivate researchers to better release their independent innovation capabilities."... Yuan Longping especially supports the development of young people.

He has donated all kinds of bonuses and manuscript fees he has obtained, and also specially set up the "Agricultural Science and Technology Award Fund" to encourage and support agricultural scientific research workers.

  "Many of the national Mesozoic scientific researchers were students of Yuan Longping or received his guidance. Now they are all experts in their own right, and they are the backbone of hybrid rice breeding and scientific research." Huang Fasong, former deputy director of the China Rice Research Institute Say.

  Today, Hunan Hybrid Rice Research Center also has a strong team of scientific research talents in the field of basic and cutting-edge major scientific issues in the field of hybrid rice, as well as key technologies for the sustainable development of hybrid rice production.

  Entering the State Key Laboratory of Hybrid Rice located in the center, and continuing to inherit the scientific research strength of "relying on the cool dream" makes people full of confidence: the national candidate of the Hundred Thousand Talents Project, the winner of the National Outstanding Youth Fund, and the winner of the National Outstanding Youth Fund , Young and middle-aged scientific and technological innovation leading talents of the Ministry of Science and Technology...

  "It can be said that the current laboratory personnel structure is reasonable and the echelon is good, which can ensure the continuous leading position of my country's hybrid rice in the whole field." Wu Jun introduced that in the research of rice heterosis mechanism, germplasm innovation and gene discovery, hybrid rice variety cultivation, etc. In different disciplines, a scientific research team has been formed with a group of "post-60s" leaders and "post-70s" and "post-80s" as the backbone.

In the past two years, a group of "post-90s" have even emerged one after another.

  The goal of "higher yield and higher yield" throughout Yuan Longping's life is still the direction of these researchers' efforts.

In their respective positions, they continue to work towards a common dream.

  Born in 1985, Li Jianwu, director of the cultivation room of the Hunan Hybrid Rice Research Center, has another identity on the video platform—the blogger "Dr. Li teaches you to grow rice" with nearly 8 million likes.

In the video, he stands in a rice field with a dark complexion, sharing the latest work progress with fans and answering questions for farmers.

  From winter to summer, from cotton clothes to short sleeves, videos have witnessed his days with rice.

Li Jianwu firmly remembered that Yuan Lao often said that "books and computers can't grow rice." More than 70% of the time is spent in the fields.

  Since Yuan Longping proposed and designed the "one-third of the land" food high-yield, green and high-quality scientific and technological innovation project (referred to as the "Sanyi Project") in 2018, Li Jianwu has been the main person in charge of the project.

In 2021, the "Sanyi Project" will increase the output of grain by 209,000 tons, with an additional economic benefit of 430 million yuan.

In October of the same year, Li Jianwu and his colleagues raised the record per mu of the third-generation hybrid rice from 1,530.76 kg in 2020 to 1,603.9 kg.

  In 2021, Deng Qiyun, a super rice breeder and chief scientist of Hunan Yuanchuang Super Rice Technology Co., Ltd., will make substantial progress in the breeding of heat-resistant super rice.

"I hope to deliver it to tens of millions of farmers and contribute to national food security. We will continue to work hard on the breeding of high-yield, high-resistance, high-quality, high-efficiency, and high-quality 'five high' super rice! "Deng Qiyun said.

  Today, modern information technologies such as artificial intelligence and big data are also injecting impetus into the rapid upgrade and iteration of modern breeding technology.

"These can provide strong scientific and technological support for opening up the innovation chain and industrial chain, maintaining the international competitiveness of the rice seed industry, and ensuring national food security." Wu Jun said that he hoped that in the future, the team will continue to focus on scientific and technological innovation, platform construction, talent training, etc. We can continue to reach new heights in all aspects and make greater contributions to national and world food security.

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