This study was funded in part by NIH grant no.U01A135894-01 and funds by CONCYTEC, Lima, Peru.The authors thank J.D. Moro, N. Perez-Palma, J.B. Phu, D.Sara, Amanda Chavez and Eva Casas for editorial help.We also thank Armando Gonzales, Cesar Gavidia, NestorFalcon for helpful comments and M. Gamarra and R.Zarate from Tupac Amaru for their cooperation.

This study was funded by Consejo Nacional de Ciencia y Tecnolog ??a (CONCYTEC).We wish to thank Dr. Peter Schantz for manuscript review and the people and authoritiesof the farming cooperative of Tupac Amaru in Junin, Peru.