In fact, in order to ensure that there will be no large-scale famine, countries will reserve a large amount of food every year; In addition, it will ensure that the self-sufficiency rate of grain is above 95%, because once the self-sufficiency rate of grain is below 95%, other countries are likely to choke themselves by restricting grain trade.
China has done a very good job in this respect, with the annual self-sufficiency rate of grain reaching over 95%. Even though it was difficult for foreign grain to be exported to China during the epidemic last year, it had no impact on China's grain price and supply.
However, high self-sufficiency rate of grain does not mean safety, and high self-sufficiency rate of grain seeds is necessary. However, China is not doing very well in this respect, and it needs to import 70,000 tons of foreign seeds from abroad every year, which leads to the problem of sticking its neck.
Then the question is, since China imports a lot of seeds every year, why not allow farmers to keep their own seeds?
The bargaining chip of agriculture: seeds
Before Mendel unveiled the law of biological inheritance, people cultivated seeds mainly through artificial selection, and artificially selected seeds with full particles, large particles and high yield, and then used them for planting in the next season. This method of seed selection has lasted for thousands of years. In the past, people often kept their seeds in rural areas to get a bumper harvest.
But now you will find that farmers will not keep their own seeds, but buy seeds from the market, and the seeds bought in the market will say "Don't keep your own seeds". Does this mean that seed companies are worried that no one will buy seeds, so they take various measures to prevent farmers from keeping their own seeds?
In fact, this idea is wrong. The reason why seed companies do not advise farmers to keep their own seeds is that it is difficult to ensure the high yield of the next generation. The reason is that many seeds are heterozygous, not homozygous, which will lead to much lower seed yield.
According to FAO data, at present, 80% of the total grain output growth depends on the increase in output, and 60%~80% of the increase in output comes from the contribution of improved varieties. This can also be seen from the improvement of grain output in China. 1949, China's grain yield per mu was only 68.6 kg, while in 20 18, China's grain yield per mu reached 374.7 kg. The increase of yield per mu depends not only on chemical fertilizers and pesticides, but also on the large-scale renewal and iteration of seeds.
After Mendel unveiled the biological genetic law, experts will use the biological genetic law to select different individuals with high yield, good disease resistance and strong lodging resistance, and then integrate these advantages into the same variety through various breeding methods such as hybridization, selfing and backcrossing.
After several rounds of experiments, if the variety still performs well, it will be approved for marketing before it reaches farmers.
The seeds cultivated by breeding companies usually perform well in the first year, but the disadvantage is that they can't keep their own seeds, because these seeds are not pure, but hybrids. After the seeds of hybrids are re-sown, their hidden shortcomings will appear, leading to a decline in yield.
In addition, the price of seeds sold by breeding companies is not high. Compared with the loss of keeping seeds, it is much more cost-effective for farmers to buy seeds than to keep seeds, so breeding companies do not recommend farmers to keep seeds.
Why does China import seeds?
According to the data of China Seed Trade Association, China imported nearly 70,000 tons of seeds in 20 19, most of which were vegetable seeds.
However, in order to ensure that China's grain seeds are not blocked by foreign countries, the self-sufficiency rate of rice and wheat seeds in China has reached 100%, and the self-sufficiency rate of corn seeds is low, but it has also reached 95%. The self-sufficiency rate of vegetable seeds is low, only 87%, among which spinach, cauliflower, carrot and onion are highly dependent on foreign seeds, reaching 85%-90% or even higher. Tomatoes, eggplant and other vegetables are also highly dependent on foreign seeds, reaching about 80%, which means that once these seeds are cut off from abroad, we may not be able to eat these vegetables.
In fact, some vegetable varieties in China have been stuck by foreign countries. For example, in 20 15, the price of Japanese broccoli seeds was only 3,500 yuan per bag, but by 20021year, the price had risen to more than 20,000 yuan. However, even if the price rises, China will buy it, because the varieties of broccoli in China are not good enough and the yield per mu is not high.
And peppers. Domestic pepper seeds can only be harvested twice, and foreign seeds can be harvested three times. And the shape is better, the commodity value is higher and the price is higher. This has led to the embarrassing situation that "imported seeds are sold by the grain and domestic seeds are sold by the catty".
Although China can ensure the self-sufficiency rate of seeds in grain, there is still a bottleneck phenomenon, that is, the gene pool of seeds is not rich enough, and the gene pool is the source and foundation for cultivating new varieties. Without a rich gene pool, it is impossible to cultivate new varieties needed by the market.
Therefore, vegetables in China are heavily dependent on imported seeds. For example, Shouguang, known as the hometown of vegetables in China, spent 600 million yuan on seeds around 20 10, of which nearly 400 million yuan was used to buy foreign seeds.
Why are you stuck in the neck by foreign countries?
The reason why China's crop seeds are stuck by foreign countries stems from the past ignorance of China's agriculture. For example, China is a big soybean planting country and a country of origin. However, before 1949, Americans kept collecting China soybeans from the northeast of China, and sent a plant delegation to visit China in 1974, and collected a large number of wild soybean plants in the northeast, Nanjing and Shanghai. At that time, China didn't realize the importance of these plants, but regarded them as grass. Unexpectedly, Americans used these wild soybeans to apply for a number of patent protection requests, which led to the use of our own soybeans for breeding, which was an infringement.
Besides the lack of provenance protection, the breeding methods in China are still relatively backward. Many breeding companies do not invest much in developing new varieties, and the new varieties cultivated are limited, which leads to China's lagging behind developed countries in breeding.
But now our country has begun to pay attention to this aspect and give strong support.