Genome-Wide Association Study for Multiple Biotic Stress Resistance in Synthetic Hexaploid Wheat

Authors

Madhav Bhatta, University of Nebraska-LincolnFollow
Alexey Morgounov, CIMMYT
Vikas Belamkar, University of Nebraska-LincolnFollow
Stephen N. Wegulo, University of Nebraska-LincolnFollow
Abdelfattah A. Dababat, CIMMYT
Gul Erginbas-Orakci, CIMMYT
Mustapha El Bouhssini, ICARDA
Pravin Gautam, BASF Agricultural Solutions Nebraska Research Station
Jesse Poland, Kansas State UniversityFollow
Nilufer Akci, Central Field Crop Research Institute
Lutfu Demir, Maize Research Station
Ruth Wanyera, KALRO
P. Stephen Baenziger, University of Nebraska-LincolnFollow

Document Type

Article

Date of this Version

2019

Citation

Int. J. Mol. Sci. 2019, 20, 3667

Comments

© 2019 by the authors.

Open access

doi:10.3390/ijms20153667

Abstract

Genetic resistance against biotic stress is a major goal in many wheat breeding programs. However, modern wheat cultivars have a limited genetic variation for disease and pest resistance and there is always a possibility of the evolution of new diseases and pests to overcome previously identified resistance genes. A total of 125 synthetic hexaploid wheats (SHWs; 2n = 6x = 42, AABBDD, Triticum aestivum L.) were characterized for resistance to fungal pathogens that cause wheat rusts (leaf; Puccinia triticina, stem; P. graminis f.sp. tritici, and stripe; P. striiformis f.sp. tritici) and crown rot (Fusarium spp.); cereal cyst nematode (Heterodera spp.); and Hessian fly (Mayetiola destructor). A wide range of genetic variation was observed among SHWs for multiple (two to five) biotic stresses and 17 SHWs that were resistant to more than two stresses. The genomic regions and potential candidate genes conferring resistance to these biotic stresses were identified from a genome-wide association study (GWAS). This GWAS study identified 124 significant marker-trait associations (MTAs) for multiple biotic stresses and 33 of these were found within genes. Furthermore, 16 of the 33 MTAs present within genes had annotations suggesting their potential role in disease resistance. These results will be valuable for pyramiding novel genes/genomic regions conferring resistance to multiple biotic stresses from SHWs into elite bread wheat cultivars and providing further insights on a wide range of stress resistance in wheat.