Submitted to: Plant and Animal Genome VX Conference Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 9/25/2003
Publication Date: 1/10/2004
Citation: Pan, Y., Burner, D.M., Wei, Q., Cordeiro, G.M., Legendre, B.L., Henry, R.J. 2004. New saccharum hybrids in s. spontaneum cytoplasm selected with RAPD and microsatellite markers [abstract]. Plant and Animal Genome Abstracts. P235:130.
Technical Abstract: Identification of sugarcane F1 hybrids is difficult when selections are solely based on phenotypic traits. The objective of this study was to develop Saccharum hybrids in the cytoplasm of S. spontaneum with selections based on both phenotypic traits and molecular markers. Two crosses were made between Djatiroto, a clone of Saccharum spontaneum, and LCP 85-384, a commercial variety (Cross 97-3144), or CP 62-258, an elite clone (Cross 97-3146). Prior to crossing, the maternal inflorescences of Djatiroto were emasculated by submersion in a circulating 45oC hot water tank for 10 minutes to avoid self-fertilization. Cross 97-3144 had two female tassels that produced 4.7g of seed with 338 viable seeds per gram; Cross 97-3146 had one female tassel that produced 2.4g of seed with 166 viable seeds per gram. After germination in the greenhouse, 96 progeny from each cross were transplanted to the field. Evaluations on stalk diameter (mm), Brix, and a RAPD marker OPA-11-366 were conducted on the first-ratoon crop the following year. The OPA-11-366 RAPD marker was reproducibly amplified through PCR from both sugarcane clones, but not from the maternal S. spontaneum clone. Fifty progeny (52.1%) from Cross 97-3144 and 36 progeny (37.5%) from CROSS 97-3146 produced the RAPD marker and were thus true crosses. Putative F1 progeny were selected from both crosses on the basis of large stalk diameter and high Brix, and the ability to produce the RAPD marker. These progeny were assigned US designations based on the year of selection. Progeny US 99-43, US 99-44, US 99-45, US 99-46, and US 99-47 were selected from Cross 97-3144, and US 99-48, US 99-49, US 99-50, US 99-51, and US 99-52 were selected from Cross 97-3146. The hybrid nature of the selected progeny was also verified by the presence of male-specific microsatellite markers. This is the first report on the development of Saccharum hybrids in the cytoplasm of S. spontaneum through a combination of conventional and molecular breeding approaches. Availability of these F1 hybrids could enhance the genetic diversity of Saccharum germplasm and enable sugarcane geneticists and breeders to explore the possible contribution of S. spontaneum cytoplasm in the development of new sugarcane cultivars.