Pedigree of Rf8. Each box represents a cross. Plants were either backcrossed to (normal [N]) W64A (rf1/rf1, Rf2/Rf2, rf8/rf8) or test crossed to (N) wx1-m8 (rf1/rf1, Rf2/Rf2, Rf8/Rf8). Transcripts associated with Rf8 were identified from the 1994 generation. The 1997 mapping population is a BC3 generated from one cross. The 2008 mapping population is a BC4 generation and is generated from 10 1997 individuals possessing the Rf8-associated 1.42-kbp transcripts. Plants grown for fertility observation in 2009 are progeny from crosses BC6, BC5TC1, BC4 (2008 cross only), BC6TC1, BC5TC2, BC7TC1, and BC6TC2. T, Texas.