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Rice blast disease, caused by fungus pathogen Magnaporthe oryzae , is one of the most destructive diseases that impact rice farming. In the worldwide, rice harvests lose 10% to 30% of the total production because of blast infection, which is estimated to be enough for feeding 60 million people (Skamnioti and Gurr, 2009). The most cost-effective approach to prevent rice blast disease is by employing host resistance in rice cultivars. To date, more than 84 resistance loci have been identified by various mapping approaches (http://www.ricedata. cn/gene/). Among these, 35 R genes have been isolated, mostly by positional cloning strategy. Except Pi-d2 (Chen et al, 2006), pi21 (Fukuoka et al, 2009), bsr-d1 (Li et al, 2017) and Ptr (Zhao et al, 2018), R genes share conserved gene structure and encode nucleotide-binding site (NBS) and leucine-rich repeat (LRR) proteins (Liu et al, 2007). The relatively rapid molecular evolution of R genes results in abundant alleles and contributes to the adaptability to polymorphic pathogen effectors in nature (Jones and Dangl, 2006). For instance, at least five allelic genes have been identified from blast resistance locus Pik, known as Pi-1, Pik, Pik-h, Pik-m and Pik-p (Ashikawa et al, 2008; Yuan et al, 2011; Zhai et al, 2011, 2014; Hua et al, 2012). With respect to rice blast disease research, recently several association studies were implemented and various candidate locus were obtained (Wang et al, 2014; Kang et al, 2016). Nevertheless, research based on large-scale association population is still lack. In this study, 1005 indica varieties with 4202 high quality single nucleotide polymorphisms (SNPs) (Lu et al, 2015; Zhang et al, 2017) were inoculated with nine M. oryzae isolates. We, then, conducted a comprehensive dissection on genetic variation of rice blast resistance. The results are expected to deepen our knowledge on rice blast resistance.