Submitted to: ASA-CSSA-SSSA Annual Meeting Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: October 30, 2006
Publication Date: November 12, 2006
Citation: Rines, H.W., Porter, H.L., Carson, M.L., Ochocki, G.E. 2006. Crown rust resistance introgression from diploid oat into hexaploid cultivated oat [abstract]. In: ASA-CSSA-SSSA Annual Meeting Abstracts. ASA-CSSA-SSSA Annual Meeting, November 12-16, 2006, Indianapolis, Indiana. 2006 CDROM. Technical Abstract: New sources of resistance to oat crown rust (Puccinia coronata f. sp. avenae), the most serious disease of oat (Avena sativa L.) in the Upper Midwest U.S., are badly needed as current sources rapidly become ineffective due to pathogen virulence shifts. Resistance to a complex rust spore bulk was identified in backcross derivatives of a cross between a diploid oat (2n = 2x = 14) A. strigosa, accession CI6954SP, and hexaploid (2n = 6x = 42) A. sativa, cv. Black Mesdag, even though the sterile F1 recovered by embryo rescue, its fertile colchicine-derived octaploid (2n = 8x = 56) and backcross-one plants were all susceptible, thus indicating a role of a suppressor. Nearly equal rates of male and female transmission of introgressed resistance in backcross-four materials indicate ready male transmission of resistance. Various crosses are being made to investigate the nature of the initial suppression observed, the number of resistance genes involved, the stability of resistance transmission, and the relationship of this resistance to previously identified resistance genes for crown rust in oat.