Genetic and physical mapping of Pi37(t), a new gene conferring resistance to rice blast in the famous cultivar St. No. 1

Abstract

The famous rice cultivar (cv.), St. No. 1, confers complete resistance to many isolates collected from the South China region. To effectively utilize the resistance, a linkage assay using microsatellite markers (SSR) was performed in the three F2 populations derived from crosses between the donor cv. St. No. 1 and each of the three susceptible cvs. C101PKT, CO39 and AS20-1, which segregated into 3R:1S (resistant/susceptible) ratio, respectively. A total of 180 SSR markers selected from each chromosome equally were screened. The result showed that the two markers RM128 and RM486 located on chromosome 1 were linked to the resistance gene in the respective populations above. This result is not consistent with those previously reported, in which a well-known resistance gene Pif in the St. No. 1 is located on chromosome 11. To confirm this result, additional four SSR markers, which located in the region lanked by RM128 and RM486, were tested. The results showed that markers RM543 and RM319 were closer to, and RM302 and RM212 completely co-segregated with the resistance locus detected in the present study. These results indicated that another resistance gene involved in the St. No. 1, which is located on chromosome 1, and therefore tentatively designated as Pi37(t). To narrow down genomic region of the Pi37(t) locus, eight markers were newly developed in the target region through bioinformatics analysis (BIA) using the publicly available sequences. The linkage analysis with these markers showed that the Pi37(t) locus was mapped to a approximately 0.8 centimorgans (cM) interval flanked by RM543 and FPSM1, where a total of seven markers co-segregated with it. To physically map the locus, the Pi37(t)-linked markers were landed on the reference sequence of cv. Nipponbare through BIA. A contig map corresponding to the locus was constructed based on the reference sequence aligned by the Pi37(t)-linked markers. Consequently, the Pi37(t) locus was defined to 374 kb interval flanking markers RM543 and FPSM1, where only four candidate genes with the resistance gene conserved structure (NBS-LRR) were further identified to a DNA fragment of 60 kb in length by BIA.

Resistance Genes and Selection DNA Markers for Blast Disease in Rice (Oryza sativa L.)

“…Pi3(t) and Pi5(t), and Pi1 and Pi7(t) 45,49 ). In addition, several genes are suggested to be allelic or tightly linked (e.g., Pi2/Piz, Piz-t, and Piz-5 on chromosome 6, Pik, Pik-s, Pik-p, Pik-m, Pik-h, and Pik-g on chromosome 11, and Pita and Pita-2 on chromosome 12).…”

The Blast Resistance Gene Pi37 Encodes a Nucleotide Binding Site–Leucine-Rich Repeat Protein and Is a Member of a Resistance Gene Cluster on Rice Chromosome 1

“…1 confers partial resistance to Japanese and complete resistance to Chinese isolates of blast (Ezuka et al 1969a,b;Yunoki et al 1970;Chen et al 2005). Much of this resistance is due to the presence of Pi37 .…”

“…Stability of the constructs was checked as previously described (Qu et al 2003), and the constructs were then individually transformed into the highly blastsusceptible rice cultivar Q1063, following the methods elaborated by Hiei et al (1994). The reaction to blast infection of the primary transgenics (T 0 ) and their progeny (T 1 and T 2 ) was tested by artificial inoculation with isolate CHL1159 (Pan et al 2003;Chen et al 2005). The Pi37 donor St. No.…”

Blast Resistant Genes Distribution and Resistance Reaction to Blast in Korean Landraces of Rice (Oryza sativa L.)

“…For several decades, several genes of blast resistance were found that are effectively used to control rice blast disease in rice breeding and genetic studies (Chen et al, 2005;Ballini et al, 2008;Koide et al, 2009;McCouch et al, 1994 Piz genes in the tested rice germplasm, respectively. The previous studies described that the Pik-m of three Pik locus on chromosome 11 confer high and stable resistance to many…”

“…Since then, the inheritance of resistance has been extensively studied, and over 70 major R genes have now been reported (Chen et al, 2005;Ballini et al, 2008;Koide et al, 2009). During the last few years, considerable progress has been made to understand molecular mechanisms of M. grisea infection to rice plants and rice blast R genes [Pit, Pib, Piz, Pik, Pik-m/Pik-p, Pita/Pita-2 (Hayashi et al, 2006), Piz-t (Hayashi et al, 2004;Zhou et al, 2006), Pi-d(t)2 (Chen et al, 2004), Pii (Jeon et al, 2003), Pik-m (Zhai et al, 2011), Pi39 , Pita (Jia et al, 2002 andJia et al, 2004), Pi9 , Pid2 (Chen et al, 2006), Pi2 , Pi36 , Pi37 , Pi5 (Lee et al, 2009) and Pi3 (Shang et al, 2009)] have been identified and characterized via map-based cloning or chromosome walking.…”