Abstract Detail

Genetics Section

Babel, Cherilyn [1], McCallum, Brent [2], Fetch, Tom [3], Hiebert, Colin [2], McCartney, Curt [4].

Gene mapping stem and leaf rust resistance genes in wheat.

Stem and leaf rust are two important fungal disease of wheat. Stem rust is caused by the pathogen, Puccinia graminis Pers.:Pers. f.sp. tritici Eriks. & E. Henn. Stem rust has caused severe yield loss, including epidemics in the past. Stem rust has been under control due to the use of resistance genes in wheat cultivars. In 1999, a new race of stem rust was discovered in Uganda (known as Ug99, or TTKSK), which has virulence to widely used resistance genes. Ug99 is characterized by its virulence to Sr31, which is a widely used resistance gene in current wheat cultivars. Due to Ug99’s unique virulence a large proportion of the world’s wheat cultivars are susceptible. TTKSK has spread out of Uganda towards areas with higher wheat production, and now consists of 7 races each with their unique virulence. Few resistance genes remain effective against this new set of races and the ones with resistance will not remain effective forever. Leaf rust is caused by the pathogen Puccinia recondita Rob.ex Desm f.sp. tritici. It is the most widespread rust on wheat with a 5-15% yield loss which adds up to a substantial loss. Resistance genes are the most economical method of control. Currently there are over 70 leaf rust resistance genes characterized, many of which have been utilized in wheat breeding. Most of these resistance genes are race-specific and only remain effective for about 10-20 years, therefore new resistance genes need to be found. The purpose of this study is to map new resistance genes in the wheat DH population 6SEPMON23/RL6071. The resistant parent in this population is 6SEPMON23. Stem and leaf rust seedling tests have been performed on this population. These tests have shown that there are two resistance genes against TTKSK, and one for leaf rust races MGBL and MBRJ. The resistance genes will be located through linkage analysis using a modified version of bulk segregant analysis using the 90K Infinium SNP chip.

1 - University of Manitoba, Plant Science, 222 Agriculture Building, Winnipeg, MB, R3T 2N2, Canada
2 - Cereal Research Centre, Agriculture and Agri-Food Canada, 101 Route 100, Morden, MB, R6M 1Y5, Canada
3 - Brandon Research Centre, 2701 Grand Valley Road, Brandon, MB, R7A 5Y3, Canada
4 - Cereal Research Centre, 101 Route 100, Morden, MB, R6M 1Y5, Canada

Keywords:
linkage mapping
Gene mapping
Stem rust
Ug99
TTKSK
leaf rust
wheat leaf rust
infinium
90K SNP chip
seedling
Genetic resistance
Disease Resistance
Disease Resistance Genes
resistance genes
virulence.

Presentation Type: Poster:Posters for Sections
Session: P
Location: Hall D/The Shaw Conference Centre
Date: Monday, July 27th, 2015
Time: 5:30 PM
Number: PGN019
Abstract ID:1292
Candidate for Awards:Genetics Section Poster Award