We often think of agriculture as planting seeds and harvesting crops. But many crops do not come from seeds. Many kinds of trees

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问题    We often think of agriculture as planting seeds and harvesting crops. But many crops do not come from seeds. Many kinds of trees and plants are grown from【D1】______cut from existing trees and plants. This is called grafting (嫁接).
   Farmers cut branches or young growths, called【D2】______, from one plant and place them on a related kind of plant. The branch or bud that is grafted is called a scion (接穗). The plant that【D3】______the graft is called the rootstock. Over time, the【D4】______from the two plants grow together. The grafted plant begins to【D5】______the leaves and fruit of the scion, not the rootstock.
   A graft can be cut in several ways. A cleft graft (割接,劈接), for example, requires a scion with several buds on it. The bottom of the scion is cut in the【D6】______of the letter V. A place is cut in the rootstock to accept the scion. The scion is then【D7】______placed into the cut on the rootstock. Growth medium is put on the【D8】______to keep it wet and help the growth.
   Grafting can join scions with【D9】______qualities to the rootstock that is strong and resists disease and insects. Some common fruit trees such as sweet cherries have to be grafted.
   In an age of high-technology agriculture, grafting is a low-technology method that remains【D10】______important.
A) accepts F) desirable K) parts
B) agreeable G) extremely L) pieces
C) blossoms H) gradually M) produce
D) buds I) grow N) securely
E) composes J) joint O) shape
【D8】

选项

答案J

解析 根据句子结构可知,空格前为定冠词the,此处应填入名词。根据句意及常识可知,生长培养基(Growth medium)有助于嫁接连接处的湿润,促进生长,故应放在接合处,所以选J)joint。
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