¹ Clemson University Genomics Institute, Room 100 Jordan Hall, Clemson, SC 29634

² CIAT Headquarters, Apartado Aéreo 6713, Recta Cali-Palmira, Km 17, Cali, Colombia

We have constructed a BAC library for cassava using the clone MECU72. This clone carries resistance to the whitefly pest Aleurothachellus socialis. At the present time, the MECU72 library contains 73,728 clones stored in 192 384-well microtiter plates. A random sampling of BACs indicated an average insert size of 102 kb. Based on a genome size of 760 Mb, library coverage is approximately 10 haploid genome equivalents. We are also now in the process of constructing a second BAC library for cassava using the clone NGA2 which contains resistance to the African cassava mosaic virus (ACMV). Data from BAC library construction and characterization efforts for both libraries will be discussed. Both whitefly resistance and ACMV will be targets for map-based cloning using the BAC libraries as tools.