Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: February 20, 2005
Publication Date: March 20, 2005
Citation: Pederson, G.A., Erpelding, J.E. 2005. Progress in improving the u.s. sorghum germplasm collection. Meeting Abstract. Proceedings of the 24th Biennial Grain Sorghum Research Utilization Conf. CDROM. 2005 Technical Abstract: The U.S. sorghum germplasm collection is maintained by the USDA, ARS, Plant Genetic Resources Conservation Unit, Griffin, GA, in cooperation with the S-009 Multistate Regional Project. This collection is a source of sorghum genetic resources for researchers worldwide. In 2001, an assessment report to the Sorghum CGC suggested that up to 10,000 sorghum accessions at Griffin were in immediate need of regeneration. A plan was developed by ARS to initially regenerate sorghum accessions with low availability germination > 50%, only original seed, and in high demand by users. Currently, a total of 32,355 sorghum accessions are maintained at Griffin with 95% available for distribution and 96% backed up at the National Center for Genetic Resources Preservation (NCGRP), Ft. Collins, CO. An additional 10,183 accessionis are maintained only at NCGRP. The Sorghum CGC plans to evaluate these accessions for photoperiod sentisitivity in 2005 and move all insensitive accessions to Griffin. From 2001-2004, a total of 8,174 sorghum accessions were sent to the ARS Germplasm Introduction and Research Unit, St. Croix, for systematic seed regneration. A total of 6,101 accessions have been regenerated so far, not including 2004 material that will be harvested and added to the collection in 2005. Additionally, the sorghum industry regenerated seed of 3,639 photoperiod-insensitive sorghum accessions in 2001. These accessions were cleaned, processed, and distributed from Griffin for numerous research evaluations conducted throughout the U.S. A germination testing program was established at Griffin in 2002 and 15,697 sorghum accessions have been tested for germination. Germination testing of back-up samples at NCGRP has reduced the number of accessions with no germination data to 969 accessions. Most of these remaining accessions do not have enough seed for germination testing and will require regeneration. Sorghum seed remains viable longer when maintained at -18 C rather than 4C. During 2001, all original seed of sorghum accessions were moved from a 4C refrigerated cold room to a -18 C freezer room at Griffin. All new regenerated seed samples and other sorghum samples at Griffin are being split with the bulk of the seed maintained at -18C and a small distirbution sample maintained at 4 C. As of 2005, samples of 17,437 sorghum accessions or 54% of the collection were maintained at -18 C. In the last 5 years, almost 90,000 seed samples of sorghum accessions have been distributed from the Griffin collection for research use. Photoperiod snnsitivity testing of the Griffin collection in 2000 by the Sorghum CGC greatly increased utilization of the collection by the sorghum industry. The most rquested accessions from the collection were those that originated in Sudan and Ethiopia. Frequency of distribution since 1988 to research users varied greatly among individual sorghum accesions, ranging from 0 to > 50 times. The U.S. sorghum collection is in much better shape in 2005 than 4 years ago. However, preservation of genetic resources is a continuing process, and there is still more progress to be made. ARS and S-009 Multistate Regional Project personnel will continue these efforts to regenerate, preserve, characterize, and distribute these valuable genetic resoureces to the sorghum research community.