Different kinds of plants make the earth a beautiful place. And humans also depend on some plants, like rice and corn, for food. But what will happen if wars or natural disasters make these plants die out? Will it be really difficult for people to live?
To prepare for such risks, humans build seed (种子) banks—a type of bank where seeds from lots of different plants are kept safe. These seed banks serve as repositories of genetic diversity (基因多样性资源库), making sure that valuable plants are protected for future use.
____ Experts from all over the world collect the endangered and useful plant species (物种). Once the seeds arrive at the bank, they are divided into groups according to their looks or tastes. The workers then check the seeds with X-rays to make sure they're healthy, and all the unhealthy ones are given up. With the bad seeds gone, the good ones are then cleaned, dried and kept in the cold condition—around -20℃. It helps to protect and store the seeds, making sure they can still grow when they are needed later.
In seed banks, the strongest seeds are those of the sorghum (高粱). They will be able to live in seed banks for about 19,500 years under the right conditions. Though seed banks are a great idea, they are not perfect. For example, seed banks are not suitable for all the plant species. A 2018 study showed that 36% of endangered plant species cannot be stored in seed banks. Species like coffee and bananas need special care and cannot be stored in this way.
So more things need to be done to take care of the plants in nature. That means we should do something to protect forests, keep our planet clean, and grow plants in ways that are good for the earth. Seed banks are like a safety net, but it's really up to all of us to make sure plants can thrive (繁荣) in the future!
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