A fine rice variety is bred in this way (first-line investigation)
Source: Ministry of Agriculture and Rural Affairs, etc.
In April 2022, General Secretary of the Supreme Leader visited Hainan and came to the "brain" of Nanfan Scientific and Research Breeding Base — — Sanya yazhouwan seed laboratory. The general secretary said: "Only by grasping the seeds of China with your own hands can you stabilize China’s rice bowl and achieve food security."
Nanfan, a large number of agricultural workers’ repeated migration journey. From September every year to May the following year, they come to Hainan from all over the world to take advantage of the unique tropical climate conditions here to carry out a series of scientific research activities such as crop seed breeding, hence the name "Southern Breeding".
At the moment, it is the season of the south. Let’s follow a rice seed to observe how it will grow from creating materials to breeding and seed production.
Sampling — — Sanya, Hainan
It took 10 years to produce a good variety.
Some have just been sown or seedlings, some are heading green, and some are golden to be harvested — — Walking into the Nanfan Base in Sanya, Zhongzhong Group, you can get a glimpse of rice at all growth stages.
"The advantage of Hainan is that there are abundant light and temperature resources, and we will sow here every one or two months." Shi Yitao, assistant of rice breeding in Zhongzhong Group, is a good way in the crop field. "Farmers will, we will;" Farmers won’t, and we understand. "
For a year, he guarded the experimental field like a child, and his broad face was tanned. "Water carefully every day to observe, prevent snails, birds and mice. I want every seedling to sprout and thrive. " Shi Yitao said.
It’s windy, rainy and sunny, which is a summary of the local climate by Nanfan people.
Sowing in the hot sun, sometimes, you have to hide from the rain four or five times for half a day. Whenever it rains, Shi Yitao is on tenterhooks: when the seedlings were young, he was afraid of the heavy rain and washed up the nutrient soil and washed away the seedlings; The rice is a little longer, catching up with the typhoon. The water in the field is more than 60 centimeters, leaving an ear on the water surface. It is raining against the wind and drowning again and again. "Danger is not afraid, and nothing is important to keep the seedlings."
In the corner of the experimental field, the iron fence was deeply embedded in the soil, and a small rice field was specially taken care of. "Specially rat-proof, afraid of gnawing materials." Shi Yitao gently pulled open the iron door and walked through a ridge, and the green and tall seedlings came into view.
"these are breeding materials R1607 with low cadmium gene introduced, which is already in tillering stage." Shi Yitao bowed down and took off a piece of leaf with tweezers, about 1 cm long, and carefully put it in a deep hole plate. "I hope it will be successful in one sampling."
From the summer of 2021 to now, this batch of materials has been planted in Hainan for three consecutive seasons, plus one season in Hainan in winter of 2020 and one season in Hubei in early 2021. It has been crossing, backcrossing and selfing for more than two years, and it has been five generations. Preliminary laboratory data show that the genetic traits of low cadmium gene have already appeared in future generations.
"If there is no problem with the re-inspection data, after maturity, you can select a trial plant with the best growth and the best laboratory genetic data from these 2000 strains." Shi Yitao said.
Just pick one plant, will it be too few?
"You don’t look down upon it, the seed setting rate is very high, one plant also has one or two thousand grains, and the ear of rice is half an arm long. This is also the reason why the rice variety Youyou 607 is favored by the market. "
"If you compare Quanyou 607 to an excellent ‘ Baby ’ Then R1607 is like an excellent ‘ Father ’ 。” Zhou Hua, director of rice testing of Zhongzhong Group, said that R1607 not only aggregated 8 rice blast resistance genes and 3 lodging resistance genes, but also aggregated 17 genes of sheath blight resistance, cold tolerance, flood tolerance, nitrogen efficiency and yield. Now, after introducing the low cadmium gene, even if rice is planted in fields with excessive cadmium content, it is low in adsorption or insensitive to cadmium.
How long does it take to breed a fine variety like Quanyou 607?
"It took 10 years from breeding to variety approval!" Zheng Ruifeng, the head of the R&D team of Quanyou 607 and the director of rice breeding of Zhongzhong Group, said that the creation of new materials is very uncertain. "There have been 52 cross combinations, and finally only R1607 was bred."
The R&D team will then introduce genes against bacterial blight, rice planthopper and fragrance, etc., and constantly upgrade and transform R1607 to become an all-around champion, so that the "baby" born will be better.
What is the most difficult thing in breeding?
Zheng Ruifeng replied in this way: if the varieties that show "leverage" are planted in other places for trial planting, some unexpected situations may occur, such as not resisting high temperature, low temperature, lodging, a certain disease, or a certain climate. Sensitive, "this will make all previous efforts and investments zero."
The early research and development is difficult, but the heart is still not hanging. Once it enters large-scale production, the strings in the heart will be tightly stretched. The bigger the promotion area, the more worried it is. "If farmers fail to harvest food, we will have trouble sleeping, and we will be relieved when we harvest it." Zheng Ruifeng said.
Detection — — Wuhan, Hubei
Breeding experts wear "gene glasses"
In Wuhan, Hubei Province, the genotyping laboratory of the Life Science and Technology Center of China Seed Group, the low cadmium sample sent from Sanya base, finally ushered in the key experimental link — — DNA genetic material was extracted and analyzed.
Zhang Xiaobo, the head of the laboratory, tapped the button, and the shaker, centrifuge and PCR instrument ran one after another. The data showed that the recovery rate of differential loci was 88.7%, and the recovery rate of whole genome reached 97.5%.
What do these data mean? "This shows that the low cadmium gene has indeed been stably passed on to the offspring of R1607. After the upgraded version of R1607 matures, a new trial production process can be started." Zhang Xiaobo explained.
"In the breeding process, the laboratory and the experimental field are closely linked." Ye Rongjian, deputy director of the Technology Platform Department of the Science and Technology Center of Zhongzhong Group, said that the genetic performance after the introduction of low cadmium gene is difficult to observe by experience. "Is cadmium adsorbed into rice seeds? The naked eye can’t see it at all."
"When R1607 was first created, molecular biological breeding technology was just beginning, and we took the path of traditional cross breeding combined with molecular breeding assisted selection. Nowadays, molecular marker detection and genome breeding technology have become very common, which is like wearing a pair of glasses that can see through the function of genes for breeding experts. " Zheng Ruifeng said that intelligent breeding in the future, relying on artificial intelligence, big data and biotechnology, will be more efficient and accurate.
Of course, the powerful function of this pair of glasses depends on the breakthrough of basic research. "The reason why the introduction of low cadmium gene has achieved results for more than two years is because the functional sequence of low cadmium gene is very clear." According to Ye Rongjian, there are about 50,000 genes predicted in rice. At present, about 4,000 genes are cloned and their functions are clear. It may take many years for a gene to know its functions, and the road ahead is still very long.
"The laboratory not only undertakes the task of detection and analysis, but also explores the mystery of genes." Nie Dongming, the seed administrator, pushed open the heavy security door, and a germplasm resource bank with more than 100,000 rice materials was presented. Here, at the temperature of 4 degrees Celsius, the seeds enter a dormant state and can be safely stored for 5-mdash; Ten years.
Zhou Hua said that the germplasm resource bank is a treasure house for creating breeding materials. At that time, Academician Yuan Longping discovered the special material of wild rice sterile plant "Wild Abortion" in Sanya, and achieved the breakthrough of hybrid rice breeding.
R1607′ s breakthrough in rice blast resistance is also due to the germplasm resource bank. "At that time, we were making a breakthrough in the technology against rice blast. I heard that the Chinese Academy of Sciences discovered a gene with strong resistance, but breeding experts did not have this material at hand. We went to the germplasm resource library to search and found the original material. " Zheng Ruifeng introduced that this peasant variety was used to cross and backcross with indica rice varieties, and a series of materials containing rice blast resistance genes were bred.
"If things in nature are lost, you may not find them when you want to use them in the future. The importance of the germplasm resource bank is now more and more deeply understood. " Zheng Ruifeng said that it is a source protection when its value is not clear and the advantages of germplasm resources are not tapped.
Zhou Hua introduced that China Seed Group and Yazhouwan Seed Laboratory jointly issued a list for the first-class scientific research institutes and universities in China, and Industry-University-Research jointly integrated gene resources, and there were more than 10 topics in the field of rice alone. In addition to further cooperative research on low cadmium genes, there are also cooperation in herbicide resistance and rice false smut resistance. "The goal is to make excellent rice varieties full of treasures."
Seed production — — Hainan dongfang
One mu of seed production can be used for more than 100 mu of fields.
"Yanmei, throw me the seedling!" "Good, then!" Fu Yanmei didn’t lift her head. A bunch of tender rice seedlings came out and flew over eight or nine women who worked hard, drawing an arc over the paddy field and accurately "delivering" it to Zeng Yabei.
On February 3rd, gancheng town, Dongfang City, Hainan Province, after the Spring Festival, seed production and rice transplanting have been busy for more than a week. The villagers cooperated skillfully, transplanting rice in the field, and there were bursts of laughter from time to time.
Such busy and cheerful scenes often appear in the process of seed production. In the whole seed production process, the most attractive thing is heading and flowering, which is also called catching powder.
At the end of October last year, in this field, the reporter witnessed a scene of catching powder. The sky clears up, the temperature rises, the male parent and female parent materials in the rice field bloom and spit, and pale yellow flowers are dotted with light green ears of rice swaying gently in the breeze. A 40-meter-long rope hangs in an arc on the ear of rice. The two workers each held one end and walked quickly forward in parallel. Where the rope passed, the ears of rice touched, the stamens trembled, the pollen floated to the pistil of the female parent, and suddenly a pale yellow powder fog was stirred in the field.
Wang Shiming, general manager of Hainan Nongle Nanfan Technology Co., Ltd. said: "Breeding is to bring a bag of seeds and carry a bag of seeds back. Seed production is different. One acre of seed production can be used for more than 100 acres of fields. "
There are many seed production processes, so it is necessary to plant seeds in reverse order to let parents meet this flowering period. For example, it takes 100 days for the male parent of Quanyou 607 to plant and 80 days for the female parent, so the male parent should plant 20 days in advance; After that, we constantly observe the leaf period, analyze the flowering period, and sometimes adjust it through water and fertilizer to ensure that the flowering period meets.
"Artificial powder driving can improve the seed setting rate of hybrid rice." Wang Shiming introduced that many years ago, there were as many as 100,000 people in Hainan from Pingxiang City, Jiangxi Province. In recent years, the country has revitalized the seed industry, and Pingxiang has also introduced measures such as subsidies for large seed producers and subsidies for grain production. Encouraged by this, many Jiangxi farmers who have produced seeds in Hainan have returned to their hometowns for development.
"Raising seedlings, transplanting seedlings, heading and pollination, harvesting and drying seeds, selecting seeds and packaging, I can play when I am young." Wang Shiming has been following his parents to Hainan for more than 20 years. His skin is tanned and he speaks slowly. In 2022, Dongfang City, where he lives, was recognized as a national seed production county, with a million mu of fertile land in Thanksgiving Plain. "Winter seed production starts at the end of December every year, and the seeds are harvested in April and May of the following year, which is just the time for the middle and lower reaches of the Yangtze River."
Affected by rising land rent and labor costs, Hainan rice seed production has been moving westward, from Sanya to Ledong Li Autonomous County, and then to Dongfang City. "The average annual land circulation per mu in the East is 1,300 yuan, but it has already exceeded 3,500 yuan in Sanya." Wang Shiming said.
In the middle and late September of 2022, Wen Mincao, deputy manager of the production department of Zhongzhong Agricultural Science and Technology Company, received an urgent task. When the seed production area of Quanyou 607 Hainan suddenly increased from the original six or seven thousand mu to more than 20,000 mu, his head was buzzing. Where can he find the producer and production base?
The Chinese company implements the order system and gives plans to manufacturers and professional teams all over the country every year. However, the farming season in the mainland has passed in winter and it is difficult to produce seeds; Although Hainan can produce seeds, it is also the winter melon and vegetable season, with less open space, high land rent and early seed delivery time. At one time, it is a bit intense to "grab the base".
Thanks to Wang Shiming’s contacts in many ways, Wenmin Cao took only one week to reach an intention on 6,000 mu of land and finally breathed a sigh of relief. "Seed production counties support the integration of production, processing, warehousing, packaging and logistics. With favorable policies, we have signed a cooperation framework for the integration of production and supply chain with local manufacturers, which can be produced locally, packaged locally and sent to the market, and can be stored locally if they are not sold out."
All the efforts are worthwhile.
In the middle and lower reaches of the Yangtze River, farmers who have tasted the sweetness have long been thinking about good seeds. In Shilou Village, Wudian Town, Zaoyang City, Hubei Province, Chen Bangguo, a large grain grower, called Qiu Yunze, a seed dealer in Wudian Town, after planting winter wheat.
"Good seeds are in demand! When we tried to plant Quanyou 607, it was Laoqiu who came to sell it, and he guaranteed it, saying that it was not good to compensate my output. As a result, two or three hundred kilograms of rice were added to an acre of land. I am happy to invite Laoqiu to eat! " Chen Bangguo said.
"In the early stage, we will build a model field display, and invite large households to go to the scene to observe the harvest and yield measurement, so that more farmers can see the comparative advantages of varieties. In the later stage, collect information about high-yield farmers, make posters, and organize seedling meetings from seedling stage to heading stage to expand influence. " Speaking of the promotion experience of good seeds, Wang Hanyong, deputy sales manager of Hubei Branch of China National Seed Group, talked endlessly.
The field of hope, season after season, the story of a fine variety will be told constantly.
Planning for this issue: Yin Xinyu, Wu Yan and Cheng Juxin