Submitted to: Journal of Plant Registrations
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: May 10, 2013
Publication Date: September 1, 2013
Citation: Klein, R.R., Miller, F.R., Klein, P.E., Burke, J.J. 2013. Registration of partially converted germplasm from 44 accessions of the USDA-ARS Ethiopian and Sudanese sorghum collections. Journal of Plant Registrations. 7(3):368-372. Interpretive Summary: Major advancements in science hinge on the identification of plant and animal germplasm that possess superior traits that are critically important to agriculture. Identifying new sources of germplasm that are unadapted, but possess traits superior to existing genetic stocks is critical to increasing the performance of our existing crops and livestock, and breeders are constantly challenged with finding and developing these new stocks. Our work focuses on improving major grain and biofuel crops and, with new germplasm types, the necessary genetic materials are available to make breeding new crops more efficient. This study details the efforts to develop new sources of sorghum germplasm from unadapted tropical stocks, which is of importance in sustainable agriculture and in biofuel production. Developing and releasing new sources of sorghum germplasm will provide scientists with the necessary raw genetic materials to make new, highly desirable grain varieties. Information will be primarily used by fellow scientists but the work should ultimately result in better adapted, higher producing crop varieties available to American farmers.
Technical Abstract: Forty-four sources of late-maturing sorghum [Sorghum bicolor (L.) Moench] germplasm (Reg. No. PI 665639 to PI 665682) were converted to early-maturing, dwarf-height enhanced F3 families, and were released by the National Sorghum Foundation, the United Sorghum Checkoff Program, the USDA-ARS, and MMR Genetics LLC in 2012. The sorghum Working Groups represented in these partially-converted materials include: Zerazera, Caudatum, Caudatum-Kafir, Caudatum-Guineense, Caudatum-Nigricans, Caudatum-Durra, Nandyal, Durra, Durra-Kafir, and Durra-Bicolor. Partial conversion was accomplished by crossing late-maturing tropical accessions to elite line BTx406 during the winter in Puerto Vallarta with selection of early-maturing, short genotypes (generally 2- or 3-dwarf) within F2 segregating populations under long-day, summer conditions in Vega, TX. Early-flowering short F2 selections were genotyped by sequencing, and five F2 plants with the greatest proportion of the exotic genome from each crossed accession were selfed in Puerto Vallarta. The resulting F2:3 germplasm families, RSC02-3seL(bulk) to RSC149-3sel(bulk), represent new sources of germplasm from the USDA-ARS collection of a height and maturity readily usable to temperate-zone areas of the world. The RSC lines should contain new sources of desirable traits such as drought and disease resistance, food quality, and grain yield. This germplasm will be useful in breeding programs by providing new genetic diversity from tropical accessions currently not available for use in hybrids.