To evaluate the value of a resource, it is necessary to look beyond the present and take a long-term view. While local varieties that have been applied on a large scale and have a mature technical model are valuable, there are still some local varieties that were once flourishing, although they can not be directly applied to production now, however, it carries excellent genetic traits, may be in the future some time, re-enter people's field of vision, play an inestimable role.

A 150-year-old kumquat tree in youxi county, Sanming City, Fujian province, not only bears witness to the development of the kumquat industry in Youxi County, also carrying the agricultural germplasm resources survey and breeding personnel's expectation.

A set of wheat from Batang County, Ganzi Prefecture, Sichuan province, records the history of farming and food culture of Tibetan compatriots. With the local"A-zhuo" industrial development, it not only led farmers to get rich, but also gradually out of the mountains, the unique nutritional value to more people.

Youxi County old tree golden orange, Batang tetraploid wheat, longshuitai old yellow corn... ... 20232023 agriculture and rural areas have released the top 10 Germplasm Resources for 2022, covering different crop types such as grain, fruit trees and vegetables. These local varieties with their own characteristics and broad prospects for development all come from the latest results of the third national crop germplasm resources census.

Some of these germplasm resources are old, some are rare and endangered. They are not only the carrier of our agricultural civilization and rich regional culture, but also the precious breeding materials containing excellent genes and fine traits. Where did they come from, how did they find them, and what are their characteristics and values? Please listen to the front-line germplasm resources census workers and breeding experts to tell these"Treasures" behind the story.

Rescue breeding of old varieties

Retaining the"Ancestor" of the characteristic industry

Agricultural germplasm resources are National Strategic Resources and the foundation of agricultural development. Our country geography climate environment is diverse, the agricultural production history is long, the agricultural germplasm resources are very rich. These seed treasures are hidden in Tianchou Mountains, rivers, lakes and seas, waiting for people to discover.

Since the founding ceremony of the People's Republic of China of the 1950s, the late 1970s and the mid-1980s, China has organized two national surveys of crop germplasm resources. In March, the Ministry of Agriculture and rural 2021 the largest nationwide survey of agricultural germplasm resources in the history of the People's Republic of China. By 2022, the census of germplasm resources has covered all the agricultural counties in the country, and more than 120,000 germplasm resources have been newly collected and transferred to the national storehouse. Among them, in addition to most of the farm soil varieties, there are some resources with a long history of"Living fossils.".

Chongqing in June, hot and rainy. In the National Citrus Germplasm Resources Nursery, located in Xiema Town, Beibei District, Chongqing, the seedlings stand tall and straight, and the leaves are green, some of them are of great concern to Jiangdong District, the head of the resource garden and deputy director of the Citrus Research Institute of Southwest University. They are the "New members" of the 2021 garden, namely You Xi Jin Gan.

"Spring and summer are critical periods for the occurrence and control of pests and diseases in annual management. The diseases and pests that occur in high season mainly damage young leaves and new shoots, so it is very important for these grafted seedlings to be treated and treated on time and not to be taken lightly for a moment." Jiangdong pays close attention to the growth of kumquat plants.

These branches are from a 150-year-old kumquat mother tree. Because the mother tree resources of citrus are already very weak in the native place, these hard-won branches are likely to be the only"Fire" of the ancient trees.

"When this resource was first transferred to the nursery, there were only a few weak branches," Jiangdong told reporters, the nursery immediately adopted the grafting technique of top grafting to propagate the mother trees of Euxikin Mandarin. Since the 2021 was introduced into the nursery, the trees have grown to over one metre in height.

What's so special about these kumquat saplings?

"Generally speaking, citrus trees live only 30-40 years, and it is rare for an old kumquat tree to grow for more than 150 years. It is of great scientific value to understand the differences between the old trees and the existing market varieties for studying the evolution of kumquat resources. The variety also fills a gap in the national citrus nursery in the collection of ancient kumquat resources, aroused strong curiosity and scientific research enthusiasm in Jiangdong.

How does this ancient kumquat resource survive to this day? What happened between finding it and entering the garden?

Chen Yuan, a resource collector and researcher at the Fujian Academy of Agricultural Sciences, is still excited to recall the joy of the discovery and the hardship of the breeding process.

This resource comes from one of the regions with the longest production of Jingan in the history of China, which is located in Baziqiao Township of Youxi County. The local rainfall is abundant, belongs to the subtropical hilly area, the mountain red soil or yellow soil rich in organic matter, soil is loose and fertile, is the best medium for citrus cultivation. Youxi County Kumquat is a specialty of Fumin Hing village, Youxi County, with its bright color, sweet and fragrant skin, crisp meat, sweet and sour taste.

In recent decades, kumquat trees have been grown in Youxi County and even in Sanming from three mother trees with an average age of more than 150 years. For local fruit farmers, the three mother trees are the"Ancestors" of the kumquat tree, which has long been under the care of a specialist, even though it can no longer be used directly for its own production.

However, with the development of urbanization, a mother tree had disappeared when the third national crop germplasm survey team came here. "When we visited Hongpai village in youxi, we found two decaying kumquat tree stumps next to an orchard belonging to a 70-year-old farmer," Chen said.

The census team and the Youxi County Bureau of Agriculture and rural development immediately began to rejuvenate the old trees. After a long period of regular maintenance, a 175-year-old mother tree finally drew out new branches. The old branches were rejuvenated by opening holes in the soil, circumcising and applying organic fertilizer.

"When the branches are about 20cm out, we cut them off and immediately send them to the National Citrus Orchard for permanent preservation at the national level." The stone in Chen Yuan's heart finally fell.

For the fruit farmers of the town of eight characters bridge, the protection of citrus trees and citrus cultivation is also a stick. The old man who had inherited the mantle of his forefathers and had grown a golden orange for half his life spoke of it as if there were never enough to say. "Only by keeping the ancestor alive can you remember the old taste."

During the census, the precious resource of Youxi County's citrus culture and the development of its industry, from being discovered, preserved and rejuvenated, to preservation and salvage breeding, was saved from extinction. Once deep in the mountains, "Old" tree stump, in the National Resources Garden to revive life.