Submitted to: Interamerican Sugar Cane Seminars
Publication Type: Abstract Only
Publication Acceptance Date: September 9, 1998
Publication Date: N/A
Technical Abstract: The primary objective of the sugarcane breeding program is the selection of superior cultivars with high cane tonnage, high sugar yield, good stubbling ability, good harvestability, and resistance to biotic and abiotic stresses. Efforts have been underway for many years to broaden the genetic base of sugarcane by crossing related species of Saccharum with elite cultivars to confer resistance to disease and insect pests, enhance vigor, and increase stalk population. We have been attempting to cross Erianthus spp. and S. giganteum with sugarcane. However, visual selection of a true sugarcane hybrid is always questionable due to selfing and potential cross contamination. Further, there has been little work in developing reliable molecular markers. Several species-specific polymerase chain reaction (PCR) primers targeting the 5S ribosomal DNA intergenic spacer were developed through molecular cloning, sequencing, and computer-assisted sequence analysis to assist in hybrid selection. We have developed primers Eri3 and Eri4 which were Erianthus spp.-specific, and primers Gig1 and Gig2 which were specific to North American Saccharum including the three cytotypes of S. giganteum (2n = 30, 60, and 90). PCR protocols are now available for hybrid selection from crosses of elite sugarcane with Erianthus spp. and S. giganteum. However, it might be difficult to develop S. spontaneum-specific primers at this locus, but we believe that it should be possible to develop clone-specific primers. The impact of several other molecular marker technologies on sugarcane breeding will also be discussed.