Plant & Animal Genomes XIII Conference

January 15-19, 2005
Town & Country Convention Center
San Diego, CA

Mapping QTLs For Waterlogging Tolerance In Wheat

M Cakir^1,4 , R Appels^1,4 , I Waters² , A Verbyla³ , F Drake-Bjockman¹ , M Carter¹ , T Setter^2,4

¹  Western Australian State Agricultural Biotechnology Centre, Murdoch University, Murdoch, W A 6150, Australia.

²  Crop Improvement Institute, Department of Agriculture, Locked Bag 4, Bentley Delivery Centre, Western Australia 6983 Australia.

³  BiometricsSA, Adelaide University, Glen Osmond 5064, SA, Australia.

⁴  Cooperative Research Centre for Molecular Plant Breeding, Suite 21, 2 Park Drive Bundoora, Vic 3083, Australia.

Waterlogging adversely affects bread wheat production globally with an estimated area of 10-15 million ha each year. It is therefore a top priority for many breeding programs to develop germplasm and release varieties with waterlogging tolerance. To identify tolerant lines and determine the genomic regions carrying tolerance genes within the wheat genome, a mapping population based on doubled haploids (DH) from a cross of Ducula-4 (tolerant CIMMYT line) and Brookton (susceptible, adapted Western Australian wheat line) parental lines was studied. DH lines and control parental lines were grown in non waterlogged or waterlogged treatments in pots. Waterlogged pots were placed in ponds at 3-4 leaf stage and pots were waterlogged to the soil surface for 6 weeks to simulate waterlogging under natural field conditions. A genetic map of the population with 184 SSR markers was used to determine significant genetic regions for shoot and root growth under waterlogged conditions and shoot growth in non waterlogged conditions. For each trait four significant QTLs (LOD> 2.0) were identified. These QTLs explained up to 34%, 17% and 22% of the variations in non waterlogged shoot growth, waterlogged shoot growth and waterlogged root growth, respectively. Notably the most significant QTLs for waterlogged root and shoot growth were located on the long arm of chromosome 7B. This study has developed new phenotyping procedures for the testing of waterlogging tolerance and identified genomic regions that provide the basis for identifying candidate genes from rice-wheat-barley comparative genomic studies.