TROPICAL YAMS AND THEIR POTENTIAL, PART 8 



3 



It is of special importance in Papua 

 New Guinea, where more than 

 30,000 persons depend on yams 

 for their livelihood (19). In south- 

 ern India D. alata yams are grown 

 and appreciated, but are secondary 

 foods. They and other yam species 

 are important crops in some but 

 not all parts of Indonesia. In Ma- 

 laysia yams are not common. In 

 the Philippines few varieties of 

 D. alata are found, but some of 

 them are unique and highly valu- 

 able. Many varieties of D. alata 

 are found throughout the South 

 Pacific islands, and the species is 

 important, but more so on some 

 islands than on others. 



Dioscorea alata has had to com- 

 pete with native species of yams 

 in West Africa, where it has be- 

 come a second or third best yam. 

 Varieties of D. rotundata and D. 

 cayenensis are usually preferred 

 because they can be pounded to 

 produce the typical dish of the re- 

 gion, a sticky dough called fufu. 

 There are few areas where D. alata 

 is unknown, however, and in Sierra 

 Leone D. alata outranks D. rotun- 

 data in importance. Almost every- 

 where it is known as water yam, 

 or the equivalent in local tongues. 

 The slight variation among Afri- 

 can forms suggests that only a 

 few varieties, and certainly not 

 many superior ones, have been in- 

 troduced. Elsewhere in Africa, D. 

 alata is even more poorly distrib- 

 uted and not of great importance. 

 Feral varieties are known in Afri- 

 ca. 



In the New World, introduced 



D. alata varieties are found chiefly 

 in the Caribbean, the north shores 

 of South America, and in scattered 

 locations throughout Central 

 America. In localized areas and 

 certain islands, especially Trinidad 

 and Barbados, D. alata is of con- 

 siderable economic importance. 

 Isolation has undoubtedly played 

 an important role in establishing 

 varieties, for the principal varie- 

 ties differ from island to island 

 throughout the Caribbean. 



In South and Central America 

 D. alata is hardly known and poor- 

 ly distributed except for isolated, 

 usually coastal pockets. A few 

 varieties were introduced in Brazil 

 years ago, and recently others have 

 been brought in. Introduced D. 

 alata competes in some areas with 

 introduced African species. 



BOTANY 

 Ethnobotany 



Although the culture of West 

 African peoples has developed 

 around the exigencies of the yam 

 (9), in only one area of Southeast 

 Asia — Papua New Guinea — has a 

 similar phenomenon occurred. 

 There, D. alata has religious and 

 psychological importance much be- 

 yond its significance as a food 

 crop. The planting of yams in two 

 types of gardens has been de- 

 scribed by Lea (19). Whereas in 

 one type of garden yams are pro- 

 duced for food, in the other they 

 are treated with elaborate care to 

 produce enormous tubers. Planting 

 of the ceremonial gardens is done 

 only by men and boys and is regu- 



