Self-incompatibility (SI) is defined as the inability of fertile hermaphrodite seed plants to produce zygotes after self-pollination. It is a widespread phenomenon  in  Poaceae. SI in several grasses is under gametophytic control of two multiallelic loci, named S and Z, which segregate independently and appear to be conserved across grass species. A third locus restoring self-fertility was reported for Lolium perenne. Switchgrass (Panicum virgatum), is a perennial autopolyploid that shows strong self- incompatibility. Our goal is, to study SI in switchgrass using L. perenne as model species. SI might be an effective hybridization mechanism to produce hybrid seed. Hybrid breeding is a promising option in perennial grasses including switchgrass, which has been proposed as major biomass producing species for biofuel production in the U.S.