174 * Technologies To Maintain Biological Diversity 



Box 7-B.— The History of Plant Collection 



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Humans have collected plants and maintained them in collections for centuries (69,79,124). One 

 of the earliest documented collecting expeditions was sent by Egyptian Pharaoh Hatshepsut in 1500 

 B.C. to obtain samples of the cedar tree. In 1492, Christopher Columbus returned to Europe with 

 seeds of a new crop: corn. Later he took European wheat to the West Indies. As a result of such activi- 

 ties, the center of production of the world's agricultural crops today may be very distant from the 

 places where the crops originated. Wheat, for example, is now a major U.S. crop for some European 

 customers. 



Botanic gardens were early repositories for the plants collected by explorers and grew in impor- 

 tance in the Middle Ages with the proliferation of pleasure gardens in Europe and the Middle East. 

 During the colonial period of the 16th to 19th centuries, botanic gardens were established throughout 

 the tropics. The palm, an important source of oil in Asia, was introduced in the early 19th century 

 to Indonesia and Malaysia through botanic gardens in Java and Singapore. The Dutch East India 

 Co. supplied trading ships with a variety of fresh fruits and vegetables from a botanic garden in its 

 Capetown colony at the end of the 17th century. 



The first botanic garden in the New World was estabhshed in 1766 by the British to acclimatize 

 South Sea Island crops on St. Vincent (79). Captain WiUiam Bligh sought to introduce varieties of 

 the starchy Tahitian staple, breadfruit, to British colonies. His first attempt ended in a well-known 

 mutiny, but a later voyage in 1793 succeeded, and he brought six varieties of breadfruit to the botanic 

 garden in St. Vincent. Though first rejected by the local population, breadfruit eventually became 

 a regular part of Carribean diets. The garden at St. Vincent was instrumental in the introduction 

 of many other important crops and spices to the Americas. 



Medicine provided an important impetus to developing collections at many botanic gardens (79). 

 These gardens were essential units within medical schools and similar institutions. The chemicals 

 in many of these plants formed the basis for the pharmaceuticals industry, and some remain impor-^, 

 tant sources for modern medicines (110). ^ 



Unhke many gardens of the 18th century, the Royal Botanic Gardens at Kew, England maintained 

 a variety of plants, not just those of medical importance (79). Scientists at Kew developed a collection 

 that today exceeds 50,000 species from throughout the world. Kew has been involved in the introduc- 

 tion of many agricultural crops important to Europe and North America, such as the tomato, potato, 

 and rubber tree. 



Introducing new crops became an official activity of the U.S. Government in 1819, when the Sec- 

 retary of the Treasury enlisted the help of foreign diplomats and U.S. Navy personnel to collect plants 

 from abroad. Prompted initially by the desire to introduce new plants and later by concern over loss 

 of crop germplasm, the Federal Government instituted various national systems to collect, describe, 

 maintain, evaluate, and distribute plant germplasm. These activities evolved to what is today the Na- 

 tional Plant Germplasm System (115). 



search on the origins of plants have enabled 

 scientists to locate regions rich in diversity of 

 crop species. The regions where most of the 

 major crop species were originally domesti- 

 cated and developed are known as centers of 

 diversity, after a scheme first proposed by bot- 

 anist N.I. Vavilov of the Soviet Union (45,57). 

 At least 12 centers of diversity are now recog- 

 nized (figure 7-1). Primitive varieties and related 

 wild species that are able to survive in diverse 



habitats and resist a variety of crop-specific dis- 

 eases can be located in these areas. 



Some guidelines are available for collecting 

 a genetically diverse sample (12,47). For in- 

 stance, plants growing in areas of different soil, 

 water, or light conditions may represent types 

 that have genetic adaptations and could prove 

 to be valuable sources of particular genetic 

 traits. But guidelines for collecting seeds or 



