Submitted to: American Society of Sugar Cane Technologists
Publication Type: Abstract Only
Publication Acceptance Date: May 20, 2005
Publication Date: July 20, 2005
Citation: Tew, T.L., Pan, Y. 2005. Molecular Assessment of the Fidelity of Sugarcane Crosses with High-Throughput Microsatellite Genotyping. Journal of the American Society of Sugar Cane Technologists. 25:119. Available: http://www.assct.org/journal/journal.htm Technical Abstract: With the recent advent of high-throughput microsatellite genotyping in sugarcane, breeders now have an effective means to assess the fidelity of sugarcane crosses. Cross fidelity was defined as the proportion of progeny within each cross that inherited microsatellite DNA fingerprints from both parents. A total of 76 crosses were assessed, of which 48 had most or all of the following pollen constraints imposed on the designated parents at the time of crossing, namely 1) tassel trimming of designated females, 2) hot-water emasculation of designated females, 3) inclusion of only two parents per cubicle, and 4) use of fully enclosed cubicles (all four sides); while 28 crosses had none. For each cross, 20 randomly sampled seedlings, along with the two parents and positive and negative controls were fingerprinted. Six microsatellite markers were employed in this study; however, within each cross, only two microsatellite markers that best differentiated the parents were used. Among the 48 crosses where pollen constraints were in effect, most had a fidelity rate above 80%. Among the 28 crosses where pollen constraints were not in effect, fidelity ranged from 0 to 95% and the average being below 50%. The results of this study highlight the importance of imposing as many pollen constraints on the female parents as is practical.