Inheritance studies using 11 Arabica coffee varieties varying in CBD resistance revealed three major genes on separate loci [42] . The highly resistant variety, Rume Sudan originating from the Boma Plateau in southern Sudan, carries the dominant R- and the recessive k-gene. The R-locus has multiple alleles with R1R1 in Rume Sudan and R2R2 in Pretoria, which also carries the recessive k-gene. The moderately resistant variety K 7 carries the recessive k-gene. Clone 1349/ 269 of the variety Hibrido de Timor and its hybrid Catimor carries one gene for CBD resistance on the T-locus with intermediate gene action.