In the past, it took 200 kilograms of potato chunks to grow one acre of potatoes. In the future, only 2 grams of seeds will be needed.
On the evening of June 24, the international top academic journal "Cell" magazine reported online the breakthrough made by Chinese scientists in the field of hybrid potatoes, a scientific research project called "Excellent Potato Project" proposed and implemented by the team of Huang Sanwen of the Shenzhen Institute of Agricultural Genomics of the Chinese Academy of Agricultural Sciences, who successfully cultivated the first generation of hybrid potatoes and achieved a breakthrough from 0 to 1.
Chinese generic varieties were bred 60 years ago
The potato is the world's most important tuber-based food crop, with 1.3 billion people worldwide feeding on potatoes. Unlike cereal-based food crops, cultivated potatoes are homologous tetraploid species that rely on potato chunks for asexual reproduction. Due to the complexity of tetraploid inheritance, the process of genetic improvement of potatoes has been slow, and some hundred-year-old potato varieties are still widely cultivated.
For example, The American fries processing variety Russet Burbank, which was bred in 1902, is still the largest variety in the United States. The largest cultivar in China, Kexin No. 1, was bred in 1958 and has been cultivated for more than 60 years. One of the major challenges facing the potato industry is the low reproductive coefficient of potato blocks, the high cost of storage and transportation, and the susceptibility to carrying diseases and insect pests.
Hybrid seeds replace potato nuggets for propagation
Trace the birth of the "Youshu No. 1" hybrid potato
In order to completely solve the problems faced by the potato industry, with the support of the Ministry of Agriculture and Rural Affairs, the Chinese Academy of Agricultural Sciences and Shenzhen Municipality, Huang Sanwen, a researcher at the Institute of Genomics, and Yunnan Normal University and other advantageous units at home and abroad launched the "Excellent Potato Project", that is, the use of the theory and method system of "genome design" to cultivate hybrid potatoes, the substitution of double sports seeds for quadruple sports seeds, and the replacement of potato block propagation with hybrid seed propagation. This is a new underlying technology for potato breeding and reproduction, and a disruptive innovation for the potato industry.
Zhang Chunzhi, a researcher at the Shenzhen Institute of Agricultural Genomics of the Chinese Academy of Agricultural Sciences, told Shenzhen Satellite TV & One Shenzhen Client reporter that the traditional potato breeding cycle is very long, taking 10 to 15 years; and breeding is unpredictable. "Now with the help of genomic tools, the whole genome is detected, which means that each gene knows exactly what it looks like, so this selection is very precise and fast."
At present, double sports species have become a research hotspot in the global potato community, and scientists in the Netherlands, China and the United States have called for diploid research and breeding work.
Achieving diploid hybrid potato breeding requires overcoming two key obstacles: incompatibility and decline in inbredness. The former refers to the phenomenon that plants do not produce seeds after pollination from flowers, and the latter refers to the decline of physiological functions of organisms after self-inbringing, which is manifested in decreased vitality, weakened resistance, and reduced yield. In the previous research, Huang Sanwen's team solved two major problems through scientific means such as genome editing technology, system analysis, and gene big data.
On this basis, Huang Sanwen's team used the advantages of genomics research to use genomic big data for breeding decisions and established a hybrid potato genome design breeding process, which mainly includes four links:
1
The first step is the selection of starting material for the cultivation of inbred lines, based on the low degree of genomic heterozygoticity and fewer number of harmful mutations of the starting material;
2
The second step is the genetic analysis of the inbred population of the starting material, mainly based on the whole genome partial separation analysis and phenotypic evaluation, to determine the distribution of large-effect harmful alleles and excellent alleles in the genome;
3
The third step is the selection of inbred lines, which selects the elimination of harmful mutations with large effects according to the prospect and background, and aggregates excellent alleles, especially to break the linkage between harmful mutations and excellent alleles with large effects;
4
The final step is the selection of hybrids, according to the results of genome sequencing, the inbred lines with high genome complementarity are selected for hybridization, and the hybrids with significant heterosis are obtained.
"Youshu No. 1" yields hybrids with significant advantages
Good cooking quality
Using the above process, the team has developed the first generation of high purity (>99%) diploid potato inbred line and hybrid potato strain "Youshu No. 1". The community test showed that the yield of "Youshu No. 1" was close to 3 tons/mu, which had significant yield heterosis advantages. At the same time, "Youshu No. 1" has the characteristics of high dry matter content and high carotenoid content, and the cooking quality is good.
Huang Sanwen, a researcher at the Shenzhen Institute of Agricultural Genomics of the Chinese Academy of Agricultural Sciences, said that compared with scientists in the Netherlands and the United States, the biggest innovation of Shenzhen scientists lies in the mastery and development and utilization of genome design tools, "The whole genome design and breeding tool we have can increase the purity of inbred lines to nearly 100%, and the current degree in Europe can only reach about 80%. ”
Yuan Longping once praised the "good potato plan"
Call it disruptive innovation
The "Sweet Potato Project" is also a scientific research project concerned by Academician Yuan Longping, a famous agronomist and the "father of hybrid rice". In November 2020, Huang Sanwen's team led the first generation of genome design breeding to obtain diploid potato hybrid seeds, paid a special visit to Academician Yuan Longping, and introduced to him in detail the breakthrough progress of the "Excellent Potato Project" research. Yuan Longping believes that replacing potato block propagation with hybrid seeds can effectively solve major potato industry problems.
"There are hundreds of millions of acres of idle winter fields in southern China that are suitable for growing potatoes, and after the rice harvest, some of them can be planted with hybrid potatoes for another season." Huang Sanwen said that in addition to making rations or feed, hybrid potato cultivation can also provide additional guarantees for food security.
At that time, Yuan Longping was very happy after listening to the report, saying that the propagation of potato seeds can not only solve the problem of viral disease hazards in production, but also solve the problem of seed potato storage and transportation.
Planting an acre of potatoes requires only two grams of seeds
Large-scale production is expected within five years
The successful breeding of "Youshu No. 1" proves the feasibility of hybrid potato breeding, and makes potato genetic improvement enter the track of rapid iteration. Potatoes have been cultivated on potato nugget propagation for thousands of years, and previously it used to take 200 kilograms of seed potatoes to grow one acre of potatoes; now only two grams of seeds are needed per acre.
According to reports, researchers have begun to carry out small-scale experiments, hoping to solve some of the problems involved in large-scale seed sowing, such as seed seedlings, transplanting and other issues, and reserve some technologies required for industrialization in advance.
Content source: Shenzhen Satellite TV DeepView News
Source: Shenzhen News Network