Submitted to: Wheat Newsletter
Publication Type: Other
Publication Acceptance Date: March 1, 2002
Publication Date: October 3, 2002
Citation: Faris, J.D., Miller, J.D., Klindworth, D.L. Items from north dakota: the usda-ars cereal crops research unit. Annual Wheat Newsletter 48:249-251. Technical Abstract: Progress in wheat and durum genetics and pathology research conducted at the USDA-ARS Cereal Crops Research Unit is reported. A summary of the various projects reported on is as follows: 1) Novel genetic techniques were used to target markers to genomic region containing the free-threshing gene Q. A chromosome walk has been initiated at the Q locus and markers within 0.1 cM have been identified. 2) Tsn1 is a gene that confers sensitivity to a toxin produced by the tan spot fungus. Several markers tightly linked to Tsn1 have been identified using genomic targeting methods and will serve as a basis for initiating a chromosome walk to clone the gene. 3) Segregation distortion loci on chromosome 5B were analyzed and found to be active only in male meiosis. 4) A durum/Aegilops speltoides chromosome translocation that confers resistance to stem rust was analyzed by molecular methods and found to involve durum chromosome 2B. 5) A durum wheat line that is universally susceptible to stem rust has been developed and will be useful for stem rust genetic studies. 6) Substitution of individual chromosomes from each of two Fusarium head blight (FHB) resistant accessions of Triticum dicoccoides into Langdon durum have been completed for 10 of the 14 chromosomes. Screening of these lines indicated that chromosomes 3A, 7A, 5B, and 7B contain FHB resistance factors. In addition, FHB genes derived from the resistant T. dicoccoides accessions are being introgressed into durum cultivars. 7) Four male-sterile mutants were analyzed and three of these were found to be allelic with the previously identified male sterility gene ms1. The fourth male sterile mutant was found to be controlled by a gene on chromosome 3A and designated ms5.