|VEREMIS, JOHN - Animal And Plant Health Inspection Service (APHIS)|
Submitted to: Biomass and Bioenergy
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/23/2013
Publication Date: 2/13/2014
Citation: Hale, A.L., Viator, R.P., Veremis, J.C. 2014. Identification of freeze tolerant Saccharum spontaneum accessions through a pot-based study for use in sugarcane germplasm enhancement for adaptation to temperate climates. Biomass and Bioenergy. 61:53-57. DOI: 10.1016/j.biombioe.2013.11.015.
Interpretive Summary: Sugarcane is a crop that is typically grown in tropical climates. In the U.S., sugarcane is grown in areas where damaging freezes affect the perennial crop’s first-year establishment and yield in subsequent harvests. When a freeze kills buds which survive underground it causes the industry to lose profits because the crop does not re-emerge well the following year. Developing cold-tolerant sugarcane varieties would benefit the domestic sugar industry in cold years, and has the potential to expand the growing region of the crop in the U.S. to allow sugarcane to be a possible feedstock for a potential biofuels industry. The objective of this study was to use a bioassay to indentify sources of cold tolerance among varieties of wild sugarcane that might be utilized in future breeding efforts to develop freeze resistant sugarcane varieties. Potted below-ground stubble buds of 84 wild sugarcane varieties were put into a freezer at 20oF for six days and the number of shoots produced from the below-ground buds of frozen plants was compared to non-frozen controls. Four wild varieties were identified as having cold tolerance of below-ground buds. Urban encroachment into the traditional sugarcane growing areas of the U.S. and abroad is forcing sugarcane production to move northward into colder climates. Breeders will be able to utilize clones identified in this study as having cold tolerance as parents in traditional sugarcane breeding programs to develop varieties capable of producing sustainable and stable yields, in colder environments.
Technical Abstract: Cold tolerant sugarcane (Saccharum spp.) cultivars are important in sub-tropical production areas because they can extend the growing and harvest seasons, and increase ratooning ability. Improved cold-tolerance in Saccharum species has the potential to expand the range of adaptation of sugarcane, thus facilitating its use as a biofuels feedstock in non-traditional cane-growing areas. Selection for this trait is difficult in temperate regions because damaging freezes do not occur every year. The objective of this study was to use a bioassay to identify sources of cold tolerance among Saccharum spontaneum accessions for use in future breeding. A total of 41 S. spontaneum accessions were evaluated for survivability of below ground (stubble) buds following exposure to freezing temperatures using a growth chamber. Pots containing stubble were frozen for six days at -7 degrees C, and bud germination was determined three weeks post-treatment. Accessions identified as having more ratoon cold tolerance than the most tolerant tested commercial variety (HoCP 96-540) were IND 81-144, IND 81-80, IND 81-165, and MPTH 97-216. These clones will be used in future crossing efforts, and their progeny will be evaluated for cold tolerance under natural conditions in colder climates.