ISBN: - 978-93-88936-09-5 1.4 (E) Replantation Replanting for encouraging replantation of old and uneconomic areas with high yielding varieties of rubber, the growers must be given incentives such as the supply of highly subsidized fertilizers, subsidies for controlling leaf fall disease and for manuring during the immaturity period. 1.5 HISTORY AND SCIENTIFIC GROWTH OF NATURAL RUBBER NR is found in the lattices of over 2,000 species of plants belonging to 311 genera of 79 families. In 1826, Michael Faraday discovered that natural rubber has five carbon atoms in the repeat unit. Rubber was an existence millions of years ago. Columbus during his second visit to South America during 1493-96, also reported the use of the material as a “bouncing ball for playing games” by the inhabitants of Haiti. Rubber once was an ordinary forest tree in Amazon forest of America but now has been changed and remained as a cash crop for 150 years. Heavia Brazilians is an important type of rubber which has not only been cultivated everywhere but also been known for its good quality and high yield. There are also some other types of rubber which have not been preferred for cultivation because of its low yield. Let us briefly discuss about the life history and various scientific development and its uses of natural rubber. 1.5 (A) Pre-15th Century Rubber is used by Latin American Indians who collect latex from rubber trees and dry it on stick over smoky flames. 1496 : Christopher Columbus introduces rubber to Europe. During his second expedition to the New World, he finds natives of West Indies playing with bouncing balls, collects a few of them and presents them to Queen Isabella of Spain. 1530 : Peter Martyr publishes his bookde Orbe Novo, which has the earliest reference to rubber. 1703 : C.Francis Fresneau gives the first general description of the method of tapping and preparing crude natural rubber (NR). 1745 : Charles de la Condamine makes a report to the Paris Academy of Sciences for used to make water-proof fabrics, shoes, elastic bottles, bracelets, bells and balls, by natives of the Amazon valley. 1755 : Several pairs of boots of King Joseph of Portugal are sent report to Brazilian port of Para for coating with rubber latex. 16
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