The history of rubber

Rubber trees have taken root in Sri Lanka and Malaysia, but the fly in the ointment is that at that time, the planting industry in these two countries was mainly coffee, and people did not realize the great value of rubber trees. In the early 10 years when it took root in Asia, the planting of rubber trees was more for the purpose of scientific research. It was not until the 1890s that coffee rust devastated the coffee planting industry in the entire South and Southeast Asian regions. Out of the need to fill the vacancy, the rubber planting industry embarked on a road of rapid development. By 1907, the rubber plantation area in Sri Lanka and Malaysia had exceeded 300,000 hectares.

In addition to seizing the opportunity "created" by rust, the efforts of scientists have also provided a strong impetus for the development of the industry. Among them, Henry Ridley, a British scientist who was then director of the Singapore Botanic Gardens, contributed the most. His invention of the continuous rubber tapping method can be regarded as a milestone in the history of the development of the rubber industry.

Inside the rubber tree is a tissue called a milk duct, which is similar to the mammary glands in animals and is responsible for the manufacture and storage of latex. When the milk duct is ruptured by an external force, the internal pressure will "push" the latex out. Since most of the milk ducts are located in the bark, the rubber picker only needs to cut the bark and the latex will flow out of the wound. In South America, workers cut holes in tree trunks with axes. This method cuts through the bark and also damages the cambium beneath the bark. The so-called cambium is a thin layer of tissue between the bark and the xylem of the trunk. Although the cambium is thin, it is very important because both the bark and the trunk are formed by the cells in the cambium, and the trunk can only continue to grow thicker if the cells in the cambium keep dividing and growing.

Unlike the "axe opening" method, Ridley's rubber tapping method uses a special knife to cut a very shallow opening in the bark of the rubber tree, but does not touch the cambium. As a result, latex can be collected without serious impact on the health of rubber trees, which extends the availability period of rubber trees from several years to several decades. After using the continuous rubber tapping method, the production efficiency of the Asian silicone rubber product industry has been greatly improved, leaving South America far behind, and Asian countries have begun to occupy the position of the world rubber industry.

Advanced rubber tapping technology has put the South American rubber industry at a competitive disadvantage, but it is a disease that is the last blow to it. In 1905, a rubber tree disease called South American leaf blight emerged in rubber plantations in Panama. Leaf blight spread throughout Central America over the next few decades, reaching Brazil in 1930. South American leaf blight is caused by a fungus called Microcyclus ulei. This fungus likes to infect all young parts of rubber trees, especially the young leaves. The infected young leaves first appear gray spots, and then the leaves gradually twist and shrink until they turn black and die. Even if some young leaves are lucky enough to grow into leaves, the leaf blight fungus can still kill them. A large number of leaves of rubber trees infected by leaf blight will eventually die and fall off, and the vitality of the rubber trees and the ability to produce rubber will be seriously damaged.