TY - JOUR
T1 - Scarlet-Rz1, an EMS-generated hexaploid wheat with tolerance to the soilborne necrotrophic pathogens Rhizoctonia solani AG-8 and R. oryzae
AU - Okubara, Patricia Ann
AU - Steber, Camille M.
AU - Demacon, Victor L.
AU - Walter, Nathalie L.
AU - Paulitz, Timothy C.
AU - Kidwell, Kimberlee K.
N1 - Funding Information:
We are grateful to Jamie Baley, Kurtis Schroeder, Lucia Strader and Xianming Chen for expert assistance, and to Kim Garland Campbell and Scot Hulbert for critical reading of the manuscript. This research was supported by Washington Wheat Commission Project Numbers 3019-5850 (C.S., K.K., P.O.) and 3061-3564 (P.O., T.P.) and by USDA-ARS Project Numbers 5248-22000-012-00D (P.O., T.P.) and 5348-21220-003-00D (C·S.). References to a company and/or product by the USDA are only for the purposes of information and do not imply approval or recommendation of the product to the exclusion of others that may also be suitable.
PY - 2009/7
Y1 - 2009/7
N2 - The necrotrophic root pathogens Rhizoctonia solani AG-8 and R. oryzae cause Rhizoctonia root rot and damping-off, yield-limiting diseases that pose barriers to the adoption of conservation tillage in wheat production systems. Existing control practices are only partially effective, and natural genetic resistance to Rhizoctonia has not been identified in wheat or its close relatives. We report the first genetic resistance/tolerance to R. solani AG-8 and R. oryzae in wheat (Triticum aestivum L. em Thell) germplasm 'Scarlet-Rz1'. Scarlet-Rz1 was derived from the allohexaploid spring wheat cultivar Scarlet using EMS mutagenesis. Tolerant seedlings displayed substantial root and shoot growth after 14 days in the presence of 100-400 propagules per gram soil of R. solani AG-8 and R. oryzae in greenhouse assays. BC2F4 individuals of Scarlet-Rz1 showed a high and consistent degree of tolerance. Seedling tolerance was transmissible and appeared to be dominant or co-dominant. Scarlet-Rz1 is a promising genetic resource for developing Rhizoctonia-tolerant wheat cultivars because the tolerance trait immediately can be deployed into wheat breeding germplasm through cross-hybridization, thereby avoiding difficulties with transfer from secondary or tertiary relatives as well as constraints associated with genetically modified plants. Our findings also demonstrate the utility of chemical mutagenesis for generating tolerance to necrotrophic pathogens in allohexaploid wheat.
AB - The necrotrophic root pathogens Rhizoctonia solani AG-8 and R. oryzae cause Rhizoctonia root rot and damping-off, yield-limiting diseases that pose barriers to the adoption of conservation tillage in wheat production systems. Existing control practices are only partially effective, and natural genetic resistance to Rhizoctonia has not been identified in wheat or its close relatives. We report the first genetic resistance/tolerance to R. solani AG-8 and R. oryzae in wheat (Triticum aestivum L. em Thell) germplasm 'Scarlet-Rz1'. Scarlet-Rz1 was derived from the allohexaploid spring wheat cultivar Scarlet using EMS mutagenesis. Tolerant seedlings displayed substantial root and shoot growth after 14 days in the presence of 100-400 propagules per gram soil of R. solani AG-8 and R. oryzae in greenhouse assays. BC2F4 individuals of Scarlet-Rz1 showed a high and consistent degree of tolerance. Seedling tolerance was transmissible and appeared to be dominant or co-dominant. Scarlet-Rz1 is a promising genetic resource for developing Rhizoctonia-tolerant wheat cultivars because the tolerance trait immediately can be deployed into wheat breeding germplasm through cross-hybridization, thereby avoiding difficulties with transfer from secondary or tertiary relatives as well as constraints associated with genetically modified plants. Our findings also demonstrate the utility of chemical mutagenesis for generating tolerance to necrotrophic pathogens in allohexaploid wheat.
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U2 - 10.1007/s00122-009-1038-x
DO - 10.1007/s00122-009-1038-x
M3 - Article
C2 - 19407984
AN - SCOPUS:67650421557
SN - 0040-5752
VL - 119
SP - 293
EP - 303
JO - Theoretical And Applied Genetics
JF - Theoretical And Applied Genetics
IS - 2
ER -