Submitted to: Aflatoxin Elimination Workshop Proceedings
Publication Type: Abstract only
Publication Acceptance Date: 10/28/2005
Publication Date: 4/1/2006
Citation: Guo, B., Dang, P., Krakowsky, M., Holbrook, C.C., Bausher, M.G., Luo, M., Chen, H., Coy, A.E., Davis, D., Xu, W., Liang, X., Lee, R.D., Culbreath, A., Ozias-Akins, P., Kvien, C.K. 2005. Genetic and genomic approaches to improve host resistance to preharvest aflatoxin contamination in corn and peanut [abstract]. 2005. In: Proceedings of the 18th Annual Multi-crop Aflatoxin Elimination Workshop, October 24-26, 2005, Raleigh, NC. p. 70. Interpretive Summary:
Technical Abstract: Plant-host resistance is a highly desirable tactic that can be used to manage pest problems. Screening and identification of crop plant germplasm for resistant traits for crop improvement and molecular marker development will bring new genetic diversity into U.S. corn/peanut gemplasm. Using the combination of genetic and genomic approaches to elucidate crop defense pathways and understand the resistance mechanism and regulation will enhance genetic breeding for better crop cultivars and improved disease resistance. Corn inbred lines, GT-A1-1, GT-P2 and GT-P56 selected from GT-MAS:gk population, are in late stage of testing and will be released soon. Corn inbred lines, A638 (early, 100 days) and CY1 (115 days), are selected from germplasm provided from Spain and China. Several peanut lines are also selected with very low fungal colonization in the laboratory and low aflatoxin levels in the field cage studies (2 year). A peanut linkage mapping population has been developed from Tifrunner (resistance to TSWV and leaf spots) x GT-C20 (low aflatoxin and resistance to bacteria wilt) and will be used linkage map construction and QTL studies. Maize microarray, both cDNA and oligo arrays, have been used to study the gene expression profiles in response to drought stress and Aspergillus infection. Maize lines used in these studies were GT-A1-1, Tex6, A638, B73, M017, L0964, L01016, Tex205 and Tex202. Ten cross-talking genes have been identified and will be used in gene expression analysis among more inbred lines, hybrids and RILs. We have been developing EST database as tools and resources for peanut community to gain genomic information and knowledge and discover DNA-markers and genes. With the first batch of ESTs submission to public domain-GenBank in 2003, we used this information to characterize some peanut transcripts in response to peanut leaf spot disease and Aspergillus infection and drought stress using peanut cDNA microarray. Peanut seed ESTs will be completed soon with over 20,000 ESTs from 6 cDNA libraries at R5, R6, and R7 stages of Tifrunner and GT-C20.