Molecular Rs Linked Toiii

I n recent issues of The Journal several articles have appeared which decribe The American Chestnut Foundation’s breeding program for backcrossing the blight resistance of Chinese chestnut into American chestnut (Hebard 1994a). The breeding program involves repeated crossing of selected C. dentata x C. mollissima hybrids and progeny to C. dentata (American chestnut), hence reconstituting the C. dentata genome with the addition of genes that condition resistance from C. mollissima (Chinese chestnut). Recent issues of T%e Journal have also discussed the application of molecular markers in the backcross breeding program and advantages that such markers offer (Mulcahy and Bernatzky 1993; Ellingboe 1994; Hebard 1994a; Hebard 1994b). Ellingboe / (1994) pointed out two things that The American Chestnut ; Foundation hoped to gain by applying molecular markers in the backtheir I i cross breeding program. First, molecular markers and a corresponding genetic linkage map would help ACF identify the markers that bracket