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Brazil | soap, insect repellent |
"Hevea brasiliensis is the source of virtually all the world's rubber production. Cutting the bark of this tree releases the latex which is then collected, preserved, and stabilized. The latex is located in the inner bark of the tree and flows in the vessels of the tree. Latex is thought to be a defense against insect predators for the tree.(1)
Hevea brasiliensis was first found in the Amazon basin. The rubber trade became a mainstay of the Brazilian economy, providing at its height almost 40% of its export revenues. It was not long before the idea was conceived of domesticating rubber. However, Brazil was not the site of the successful commercialization of rubber. Rubber cultivation was, instead, transferred to Southeast Asia. Soon abundant and cheap, rubber was put to thousands of uses. Its reduced cost was an important factor in the emergence of a mass market of automobiles; from two-thirds to three-quarters of the demand for rubber soon came from the makers of tires and tubes for motor vehicles.(1) After tires, latex products, footwear, belts and hoses, and wire cables are the most important uses for rubber.(3) Rubber is harvested in Africa, Central and South America, and in Asia, the latter accounting for greater than 90% of production.
There are 11 species of Hevea. Hevea brasiliensis is a member of the Euphorbiaceae family (spurge family). Although not limited to the Euphorbiaceae, latex production is one of its distinguishing characteristics.(7)
The plants of the Euphorbiaceae family are mostly monoecious herbs, shrubs, and trees, sometimes succulent and cactus-like, and comprise one of the largest families of plants with about 300 genera and 7,500 species that are further characterized by the frequent occurrence of milky sap.(6)"
The South American rubber tree grew only in the Amazon rainforest, and increasing demand and the discovery of the vulcanization procedure in 1839 led to the rubber boom in that region, enriching the cities of Belém, Santarém, Manaus and Iquitos, Peru, of 1840 to 1913. In Brazil, the initial name of the plant was pará rubber tree. The name of the tree derives from Grão-Pará and Rio Negro or only Grão-Pará (Great-Pará), the largest Brazilian province until 1850, the capital of which is Belém, where most of the fluid, also called latex, was extracted and exported. In Peru, in addition to the hispanic-speaking countries of the Amazon region, the name given was árbol del caucho, with the fluid extracted called caucho. These trees were used to obtain rubber by the natives who inhabited its geographical distribution. The Olmec people of Mesoamerica extracted and produced similar forms of primitive rubber from analogous latex-producing trees such as Castilla elastica as early as 3,600 years ago. The rubber was used, among other things, to make the balls used in the Mesoamerican ballgame.[5] Early attempts were made in 1873 to grow H. brasilensis outside Brazil. After some effort, 12 seedlings were germinated at the Royal Botanic Gardens, Kew. These were sent to India for cultivation, but died. A second attempt was then made, some 70,000 seeds being smuggled to Kew in 1875, by Henry Wickham, in the service of the British Empire.[6]:55[7][8] About four percent of these germinated, and in 1876, about 2,000 seedlings were sent, in Wardian cases, to Ceylon (modern day Sri Lanka) and 22 were sent to the Botanic Gardens in Singapore. Once established outside its native country, rubber was extensively propagated in the British colonies. Rubber trees were brought to the botanical gardens at Buitenzorg, Java, in 1883.[9] By 1898, a rubber plantation had been established in Malaya, with imported Chinese field workers being the dominant work force in rubber production in the early 20th-century.[10] Today, most rubber tree plantations are in South and Southeast Asia, the top rubber producing countries in 2011 being Thailand, Indonesia, Malaysia, India and Vietnam.[11]
The cultivation of the tree in South America (Amazon) ended early in the 20th century because of blight.[3] The blight, called South American leaf blight, is caused by the ascomycetes, Microcyclus ulei[12] or Pseudocercospora ulei.[13]