Location: Peanut and Small Grains Research Unit
Title: Pm223899, a new recessive powdery mildew resistance gene identified in Afghanistan landrace PI 223899Author
Li, Genqiao | |
CARVER, BRETT - Oklahoma State University | |
Cowger, Christina | |
Bai, Guihua | |
Xu, Xiangyang |
Submitted to: Theoretical and Applied Genetics
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 10/5/2018 Publication Date: 12/1/2018 Citation: Li, G., Carver, B., Cowger, C., Bai, G., Xu, X. 2018. Pm223899, a new recessive powdery mildew resistance gene identified in Afghanistan landrace PI 223899. Theoretical and Applied Genetics. 131(12):2775-2783. https://doi.org/10.1007/s00122-018-3199-y. DOI: https://doi.org/10.1007/s00122-018-3199-y Interpretive Summary: Wheat powdery mildew, a globally important disease caused by the biotrophic fungus Blumeria graminis f .sp.tritici (Bgt), has occurred with increased frequency and severity in recent years, and some widely deployed resistance genes have lost effectiveness. Identification of new resistance sources is essential for breeding powdery mildew resistant cultivars. PI 223899 is an Afghanistan landrace exhibiting high resistance to Bgt isolates collected from the Great Plains. Genetic analysis indicated that a recessive gene, designated Pm223899, conferred powdery mildew resistance in PI 223899. Linkage analysis placed Pm223899 to an interval of about 831 Kb in the terminal region of chromosome 1AS, spanning 4,504,697 to 5,336,062 bp of the Chinese Spring reference sequence. Pm223389 is a new gene and confers a high level of resistance to Bgt isolates collected from Pennsylvania, Oklahoma, Nebraska, and Montana. Therefore, Pm223389 can be used to enhance powdery mildew resistance in these regions. Pm3b-1 and STARS333 can be used to tag Pm223389 in wheat breeding. Technical Abstract: Wheat powdery mildew, a globally important disease caused by the biotrophic fungus Blumeria graminis f .sp.tritici (Bgt), has occurred with increased frequency and severity in recent years, and some widely deployed resistance genes have lost effectiveness. Identification of new resistance sources is essential for breeding powdery mildew resistant cultivars. PI 223899 is an Afghanistan landrace exhibiting high resistance to Bgt isolates collected from the Great Plains. To characterize the powdery mildew resistance gene in PI 223899, an F2 population and F2:3 lines derived from a cross between PI 223899 and OK1059060-126135-3 were evaluated for response to Bgt isolate OKS(14)-B-3-1, and the bulked segregant analysis (BSA) approach was used to map the powdery mildew resistance gene. Genetic analysis indicated that a recessive gene, designated Pm223899, conferred powdery mildew resistance in PI 223899. Linkage analysis placed Pm223899 to an interval of about 831 Kb in the terminal region of chromosome 1AS, spanning 4,504,697 to 5,336,062 bp of the Chinese Spring reference sequence. Eight genes were predicted in this genomic region, including TraesCS1AG008300 encoding a putative disease resistance protein RGA4. Pm223899 was flanked proximally by SSR marker STARS333 (1.4 cM) and distally by the PM3 locus (0.3 cM). Pm223389 is a new gene and confers a high level of resistance to Bgt isolates collected from Pennsylvania, Oklahoma, Nebraska, and Montana. Therefore, Pm223389 can be used to enhance powdery mildew resistance in these regions. Pm3b-1 and STARS333 can be used to tag Pm223389 in wheat breeding. |