Submitted to: Meeting Abstract
Publication Type: Abstract only
Publication Acceptance Date: 4/22/2005
Publication Date: 4/22/2005
Citation: Cho, S., Garvin, D.F., Muehlbauer, G. 2005. High through-put genomics in small grain cereals and applications to molecular breeding [abstract]. Proceedings of the International Symposium on Plant Biotechnology. p. 30-31. Interpretive Summary:
Technical Abstract: Identification of genes associated with beneficial traits has been one of the major goals in genetics. To facilitate this process, we have applied microarray and in silico comparative genomics tools. For large-scale physical mapping of barley genes, we used the 22K Barley1 Affymetrix GeneChip to detect barley transcripts in wheat-barley chromosome addition lines harboring barley chromosome 2H, 3H, 4H, 5H, 6H, or 7H. In total, 5,543 transcripts were physically mapped to 6 barley chromosomes based on their barley chromosome-specific detection patterns. We also used the Barley1 GeneChip to identify genes at the QTL for fungal resistance in barley. Using a pair of near-isogenic lines carrying segregating alleles at the QTL region on chromosome 3H associated with DON accumulation upon F. graminearum infection, we identified 7 barley transcripts showing differential abundance between the two near-isogenic lines. By in silico comparative mapping, six genes were found on either barley chromosome 3H or syntenous wheat or rice chromosomes. We are currently conducting a similar study in wheat to identify genes for Fusarium head blight resistance at the QTL on wheat chromosome 3BS using 66K Wheat Affymetrix GeneChip. Candidate genes showing differential expression between the resistant and the susceptible near-isogenic lines were digitally mapped to barley, wheat, and rice genomes and genetic and physical linkage of these genes to the 3BS QTL is being validated. In addition to transcriptome analysis in host plants, transcriptome change in fungal pathogen through infection process is being investigated using the 18K Fusarium Affymetrix GeneChip. Simultaneous transcriptome investigation in plants and a fungal pathogen will facilitate understanding plant-microbe interaction and identification of defense response genes and potentially disease resistance genes.