Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: July 24, 2004
Publication Date: July 28, 2004
Citation: Burow, G.B., Klein, P., Klein, R.R., Mullet, J., Franks, C.D., Burke, J.J. 2004. Genetic mapping of anthocyanin regulatory genes and responses to chilling stress in sorghum [abstract]. American Society of Plant Biology Annual Meeting. Abstract p. 245. Technical Abstract: Sorghum (Sorghum bicolor L. Moench), is a tropical species that has been bred to adapt to temperate conditions. However, while sorghum conversion has been successful, its cultivation is limited by poor tolerance to low temperature or chilling conditions. To better understand sorghum chilling tolerance, genetic studies of responses to low temperature are currently being studied in a population of 132 F6 -F8 recombinant inbred lines from the cross of BTx623 (chilling tolerant) x IS3620C (chilling sensitive). Seven- to 10-day-old seedlings from this population grown at 12 and 17 C in a growth chamber under continuous light show segregation for the presence or absence of leaf anthocyanin pigments. Based on this assay, a locus for leaf anthocyanin pigmentation (SbPl) was mapped to sorghum linkage group I at approximately 74.2 cM, flanked by markers Xtxa3894 and Xtxa6015(ref. http://sorghumgenome.tamu.edu). Comparative mapping showed synteny of the SbPl region to rice chromosome 4 (between 85.5-87cM) and maize chromosome 10 (bin 10.06); genomic regions which contain anthocyanin regulatory genes. We utilized the information from comparative mapping to identify a syntenic sorghum BAC clone that harbors a regulatory gene for leaf anthocyanin production. A subclone library of this sorghum BAC clone is being analyzed to determine the genomic sequence and structure of the candidate gene. QTL mapping for a number of traits associated with the responses to chilling and their correlation to anthocyanin pigmentation will be discussed.