Submitted to: American Seed Trade Association Conference Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 10/19/2011
Publication Date: 12/9/2011
Citation: Burow, G.B., Burke, J.J., Franks, C., Xin, Z. 2011. Genetic enhancement of cold tolerance to overcome a major limitation in sorghum. American Seed Trade Association Conference Proceedings. 1.
Technical Abstract: Early season cold tolerance during stand establishment at cool soil temperature of 54ºF to 59ºF (12 ºC to 15ºC) is a key agronomic trait for warm season cereal crops such as sorghum. Sorghum (Sorghum bicolor L. [Moench]), lacks cold tolerance and is adversely affected by cool temperatures during germination, emergence/early seedling growth and at reproductive stages. To better understand the genetics of cold tolerance in sorghum, discovery of germplasm sources, hybridization and mapping of quantitative trait loci (QTL) with focus on early season cold tolerance traits were achieved. Five Chinese Kaoliang germplasm, three novel chemical mutants and two recombinant inbred populations (RIL at F7 generation) were developed. The parents, mutants and RIL populations were evaluated for cold germinability in controlled environment, field emergence, seedling vigor and biomass in multi locations during early season planting. Focusing on F7 RIL population of RTx403xPI567946, several QTL were localized in chromosomes 1, 4, 7 and 9 and identified to be associated with improved early field emergence and vigor. Particularly interesting are DNA markers for QTL localized in chromosome 9 that gave highest contribution to phenotypic variation in the population. Notably, this work demonstrated that the cold tolerance trait, specifically field emergence was not strictly associated with high tannin trait and non-tannin Kaoliang lines are valuable germplasm source of cold tolerance for sorghum.