Verification of the introgression of Erianthus arundinaceus germplasm into sugarcane using molecular markers

Erianthus arundinaceus has a number of important agronomic traits including good ratooning ability, tolerance to both drought and water logging, disease resistance and vigour and is of interest as a potential source of parental germplasm to sugarcane breeders. However, to date, attempts to produce fertile hybrids between sugarcane (Saccharum spp.) and E. arundinaceus have been unsuccessful. Microsatellite markers that generated genus-specific markers and were highly polymorphic within sugarcane were identified. The microsatellite markers and 5S rDNA PCR were used to screen intergeneric (F-1) clones from Saccharum officinarum x E. arundinaceus crosses, and two Saccharum backcross progeny (BC1) populations derived from crosses between selected F-1 clones and sugarcane (Saccharum spp.), to identify genuine Saccharum spp. BC1 progeny. The 5S rDNA PCR marker and highly polymorphic microsatellites with Erianthus-specific bands confirmed the F-1 parent of the two putative BC1 populations was a S. officinarum x E. arundinaceus hybrid and allowed the identification of the genuine BC1 progeny from selfs of the F-1 parent. This is the first verification of BC1 progeny from an F-1 intergeneric hybrid x sugarcane (Saccharum spp.) clone with molecular markers and confirms the introgression of E. arundinaceus germplasm into sugarcane. It should now be possible to exploit genes of value from E. arundinaceus in sugarcane breeding programmes.