Xin Guosheng often eats raw sweet potatoes, averaging three or four hundred per year.
Before tasting it, he had no idea what kind of challenge his taste buds would experience.
Occasionally, he tasted amazing pumpkin and potato flavors; but sometimes, his lips and teeth were swallowed by bitterness.
"You have to eat the seeds you bred with tears," Xin Guosheng joked.
Just like "Shen Nong tastes a hundred herbs", direct tasting is one of the important means for sweet potato breeders to screen excellent strains in the field.
In the breeding greenhouse of the Yantai Academy of Agricultural Sciences, Xin Guosheng, director of the Crop Institute, and his colleagues obtain about 10,000 new sweet potato strains through cross-breeding every year.
Among them, less than 5% of the strains will be "taste" by them, and even if the strains are "one-in-a-million", the vast majority will be eliminated in the second year's appraisal.
Just like looking for a needle in a haystack, they are looking for a sweet potato that combines deliciousness, high yield, and good looks, and is infinitely close to perfection.
▲Since the end of August and the beginning of September, the first crop of tobacco 25 in Shandong has gradually entered the harvest period.
After tasting thousands of varieties of sweet potatoes, in 2005, Xin Guosheng chose to keep the "extraordinarily sweet" strain No. 79.
At that time, almost all the roasted sweet potatoes on the streets in China used the varieties selected by the Chinese Academy of Agricultural Sciences in the 1950s-Yi Zi 138 and Beijing 553.
These two varieties "ruled" the "baked potato world" for more than half a century, and never encountered a strong challenger until the emergence of the 0579 strain.
It is reported that in 2012, after passing the national identification, the 0579 strain was named Yanshu 25.
Unlike many new varieties that were forgotten after leaving the test field, with the help of new e-commerce platforms such as Pinduoduo, Yanshu 25 gradually became popular online, and became one of the roasted potato varieties due to its "sweet as honey" baking characteristics. the "carrying handle".
Not only that, Yanshu 25 is also very popular with growers.
Statistics from the National Agricultural Technology Extension Service Center show that at present, Yanshu 25 has become the sweet potato variety with the largest promotion area in the country.
"Once in Decades" 0579
0579, Strain No. 79 in 2005.
According to reports, Xin Guosheng "looked at it more" among the nearly 400 strains that he chose to keep that year because it was gnawed by mice.
The use of natural enemies of plants is one of the many means for agronomists to improve the efficiency of variety identification.
That winter, Xin Guosheng left a batch of seed potatoes in the cellar, and 0579 was the most attractive for mice.
At that time, 0579 was a nascent thing, and its abilities had not been accurately identified.
In the year it was born, there was little rain in Yantai, and 0579 looked smooth and full. Xin Guosheng was very pleased.
But in the second year, the rain was frequent, and the test site occasionally accumulated water. 0579 seemed to have "varicose veins" and burst his muscles.
Xin Guosheng thought that this might be one of his countless failures.
Fortunately, regardless of taste or output, 0579 has been online and stabilized at the "Student Master" level.
This allows it to keep its "pit" in the test site for 7 years before passing the national appraisal, and avoid being eliminated.
A major pain point of variety cultivation is that quality and yield are often negatively correlated.
Delicious food is not high yielding, and high yielding food is often not delicious.
The amazing thing that 0579 gradually shows is that it has a good balance between taste and output.
In fact, the birth of advantageous agricultural products in various parts of our country is caused by accident.
0579 is no exception.
Its male parentage was ambiguous until it exhibited "high-quality sweet potato" sexual characteristics, prompting researchers to quantify the species.
Traditional sweet potato breeding often crosses a female parent with a male parent to produce several offspring.
"In order to improve the genetic potential, we innovated the breeding method at that time, using Lushu No. 8 as the female parent, and using the created backbone parents Yan 15, Yan 3, Yan 20, etc. as the male parent, we obtained 20 combinations at one time." Xin Guosheng Said that they have always followed the idea of high-quality breeding, collected high-quality varieties for a long time and established a "germplasm bank", and every day they attacked the difficult problem of "how to concentrate the advantages of parents in one offspring".
After the research team went through countless cycles of "crossbreeding, breeding, identification, and elimination", 0579 stood out.
Although it has minor shortcomings such as intolerance to waterlogging and storage, the flaws do not hide the advantages.
In the 2011 national sweet potato edible quality competition, it won the championship because of its pure taste and sweet taste; in the process of national and regional trial planting, it beat other varieties and won the first place in yield.
0579 is very precious, because even if the same female parent is crossed with the male parent again, the offspring will show vastly different sexual characteristics and may not be able to reproduce an identical one.
"More than 100 sweet potato scientific research institutes engaged in breeding work across the country have not been able to cultivate a new sweet potato variety that can replace the legacy number 138 for more than 60 years. Based on the calculation that each scientific research institute eliminates 9,000 strains per year, a single tobacco potato strain has been found. The probability of 25 is one in tens of millions." Xin Guosheng said.
"Honey Potato" selected by e-commerce
Although it has star potential, Yanshu 25, which has come out of the test site, must face the test of the market.
"Cultivation of new varieties is almost impossible, and promotion of new varieties is equally difficult." Liu Chaoli, the founder of Yimu Sweet Potatoes, was one of the first "sweet potato brokers" to promote Yanshu 25.
In 2016, she first tasted Yanshu 25, which was only grown on a small scale in Shandong and Hebei at that time. It was sweet and oily. "I have never eaten such delicious roasted sweet potatoes."
Under the recommendation of Liu Chaoli and others, Yanshu 25 began to explode online.
According to his recollection, in 2019, in the first week of selling this product on Pinduoduo, there were only 100 orders a day, but a week later, the daily order volume had soared to 4,000 or 5,000 orders.
After the market opened, the supply side was stretched.
At that time, Yanshu 25 was only planted in some high-quality sweet potato producing areas in the north. Among them, Shandong Yanwei, Hebei Tangshan and other producing areas performed well, but the output could only supply part of the domestic market.
There is a kind of "sweet potato" that sells very well in the north. In fact, this "line report" has already spread to the south.
But unfortunately, just like "the oranges in Huaibei are oranges", the tobacco 25 that was originally grown in Hainan, Yunnan and other places did not taste as good as ordinary vegetable potatoes.
"In order to ensure the stable quality of the supply, we began to contact the planting side and the scientific research side, and followed the experts from the Academy of Agricultural Sciences to run across the country to find authentic tobacco 25." Liu Chaoli said.
At the same time, in order to prevent the phenomenon of "Yanshu 25 is not Yanshu 25", agronomists such as Xin Guosheng advocated the use of virus-free seedlings.
Since sweet potato is a vegetatively propagated crop, both field seedlings and high shearing seedlings are faced with the problem of seed performance degradation caused by virus infestation.
The virus-free seedlings are induced and cultivated from the tip of the sweet potato, with "pure pedigree" and can better express the characteristics of the variety.
"The replication speed of the virus cannot keep up with the growth rate of the shoot tip. According to this principle, an important task involved in detoxification is shoot tip peeling. Our current technology can peel off a 0.3 mm shoot tip, which is similar to a hair." Xin Guosheng said .
In recent years, the Yantai Academy of Agricultural Sciences first proposed the "one size fits all" sweet potato shoot tip peeling method in China. Compared with the traditional peeling technology, the peeling speed was increased by more than 3 times, and the shoot tip seedling rate was increased by 429.7%.
The peeled shoot tips need to be placed in a container with sterile medium for cultivation, and then transplanted to a greenhouse for expansion to obtain detoxified seedlings.
In addition to the promotion of virus-free seedlings, sweet potato experts are also popularizing scientific planting methods such as deep plowing, mulching, and drip irrigation on a large scale in southern production areas.
For example, covering with mulch is the first weeding trick that Xin Guosheng thought of.
In the past, weeds often grew in sweet potato fields, and there were many pesticide residues, which were unhealthy and labor-intensive to pull weeds by hand.
This question made the growers frown, until Xin Guosheng applied a layer of black mulch to the sweet potato field, and the effect was really good.
Under the pressure of the online market and the joint efforts of scientific researchers, since 2016, Yanshu 25 has finally "grown" another key capability - excellent adaptability.
At present, Yanshu 25 has been planted in most provinces (cities) in the country, and can be supplied throughout the year.
A life changed by a sweet career
After Yanshu 25 became popular, Xin Guosheng was worried that it would only be short-lived.
With the addition of intensive processing enterprises, this variety has derived from traditional dried sweet potatoes to beverages, alcohol, ice-baked potatoes, potato honey, pectin and other innovative products.
The sweet potato that was bitten by a mouse in a corner of the cellar has now become a big industry, and the market demand for Yanshu 25 has been further expanded.
"High-tech and peculiar, we are particularly willing to plant it because it is easy to sell." In Huairen Town, Shanghe County, Jinan City, Han Chengjin, Secretary of the Party Branch of Hanwang Village, said the "high-tech and peculiar" refers to high technology, new research and development and exotic varieties. .
Yanshu 25 belongs to this category.
"In order to reduce the risk of planting, we usually set aside three to five acres of land for trial planting in the first year, and then expand the planting in the second year."
As one of the 10 village revitalization Qilu model villages focused on by Shanghe County, Hanwang Village used to mainly grow wheat, corn and other food crops.
In recent years, the village has explored the model of "village-enterprise party building consortium", developed sweet potato contract farming, and supplied products to e-commerce platforms such as Pinduoduo.
As a result, the production of more than 1,000 acres of land is all determined by sales, and high-quality varieties such as tobacco and potato 25 are planted.
"Although there was no dividend last year, we used the power of a village to raise the land rent from 800 yuan per mu to 1,100 yuan, which is equivalent to increasing the income of all members." Han Chengjin said.
On August 3, Xin Guosheng went to Shanghe County for investigation.
In Huairen, he saw the Dasha River passing through the territory, creating a unique sand planting environment.
Next year, Huairen Town plans to take out another 910 mu of land to realize the single-product cultivation of "Tobacco 25".
Yanshu 25, which changed the countryside, also changed Xin Guosheng.
"In the past, sitting on the cold bench in the laboratory, I used to doubt myself. But after 2016, some farmers earned their first million in life by growing tobacco 25. They were so happy that they even gave me a gift. The pennant. At that time, I felt that I found the value of life and tasted the sweetness of Yanshu 25. "
In the process of promoting Yanshu 25, Liu Chaoli discovered that what she wanted to do was not just selling sweet potatoes.
"We hope to discover truly high-quality varieties for consumers. Especially since this year, Pinduoduo has increased the resources of scientific and technological agricultural products in its platform strategy, and we are more motivated to allow high-quality results to enter the big market after the test field."
Liu Chaoli's next target is purple potato.
Every March and April, the search volume of purple potatoes on e-commerce platforms is much higher than that of sweet potatoes.
At that time, young people took off their bloated winter clothes and ate purple potatoes as meal replacements, but the purple potato category still lacks a "carrying handle" variety.
This time, Liu Chaoli fell in love with Dongfeng 22, a new variety cultivated by Shandong Rizhao soil expert Xu Shuliang, and started a new market test on Pinduoduo.
"The romance and charm of technology is that you can not only be a bystander, but also use it to make a little change, so that everyone can live in the world you participate in and define." Liu Chaoli believed it.