Among the factors that now limit the African yams are their 

 relatively poor yields and susceptibility to virus disease. It may 

 be possible to change these characteristics by breeding and by 

 improved culture. It is encouraging to see study being devoted 

 to the African yam in recent years, and scientists may well be 

 able to make the necessary breakthroughs. 



LITERATURE CITED 



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(2) Ayala, A., and Acosta, N. 



1971. Observations on yam {Dioscorea alata) nematodes. (Abstract) 

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(3) Ayensu, E. S. 



1970. Comparative anatomy of Dioscorea rotundata and Dioscorea 

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(5) 



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(8) 



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(9) 



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(10) , and Coursey, C. K. 



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(11) Food and Agriculture Organization. 

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(12) Gooding, E. G. B. 



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(14) Koli, S. E. 



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35 



