Genome-Wide Association Study (GWAS) Reveals an SNP Associated with Downy Mildew Resistance in Maize


  • Nay Nay Oo Doctor of Philosophy Program in Agricultural Sciences, Faculty of Agriculture at Kamphaeng Saen, Kasetsart University, Kamphaeng Saen campus, Nakhon Pathom 73140, Thailand.
  • Vinitchan Ruanjaichon National Center for Genetic Engineering and Biotechnology (BIOTEC), 113 Thailand Science Park, Pahonyothin Road, Khlong Nueng, Khlong Luang, Pathum Thani 12120, Thailand.
  • Kularb Laosatit Department of Agronomy, Faculty of Agriculture at Kamphaeng Saen, Kasetsart University Kamphaeng Saen Campus, Nakhon Pathom 73140, Thailand.
  • Theerayut Toojinda
  • Jintana Unartngam Department of Plant Pathology, Faculty of Agriculture at Kamphaeng Saen, Kasetsart University, Kam-phaeng Saen campus, Nakhon Pathom 73140, Thailand.


Preonosclerospora spp, maize, quantitative trait loci (QTL), single nucleotide polymorphism (SNP)


Downy Mildew, caused by the fungus Peronosclerospora spp. is one of the most destructive diseases of maize and can cause severe damage in crops around the world, especially in tropical Asia. Host resistance is an effective mean of control DM and is reported to be controlled by many genes. Therefore, the identification of markers linked to the target quantitative trait loci (QTL) was required in a marker-assisted breeding program. In this study, Genome-Wide association study (GWAS) analysis using 262 maize inbred lines and 434,871 single nucleotide polymorphism (SNP) markers was performed to identify genomic regions and candidate genes associated with resistance to the DM. The result showed that one significant QTL was identified on chromosome 1 associated with the trait DM resistance, containing one candidate gene, Zm00001d029516, according to its function in plant protection mechanism. This QTL/SNP locus should be validated and will be useful for marker-assisted selection and for a better understanding of DM disease resistance in maize


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