Quantitative trait loci (QTLs) for resistance to rice blast provide a potential way to obtain long lasting disease resistance in rice. chromosomal area. Electronic supplementary materials The online edition of this content (doi:10.1007/s00122-012-1852-4) contains supplementary materials, which is open to authorized users. Intro Grain blast, a harmful disease of grain, is due to the fungal pathogen (Ou 1985). Up to now, a lot more than 80 genes for blast level of resistance have been documented, which 60 are genetically mapped (Gramene data source: http://www.gramene.org/). The majority are competition specific and so are seen as a a hypersensitive response (Greenberg and Yao 2004). Nevertheless, genes for race-specific level of resistance are quickly been overcome from the pathogen (Bonman et al. 1992; Kiyosawa 1982) therefore cannot support sustainable crop production. In contrast to race-specific resistance, resistance controlled by quantitative trait loci (QTLs) is definitely characterized by a vulnerable infection type, usually without race specificity or gene-for-gene connection (Ezuka 1972; Parlevliet 1979). In general, cultivars carrying resistance QTLs have managed their resistance for a long time, probably because of decreased selection pressure against the pathogen. Therefore, the finding of QTLs in resistant cultivars is vital to our understanding of the genetic control of QTL-mediated blast resistance (Huang et al. 2011; Jia and Liu 2011; Liu et al. 2011; Shi et al. 2010). Japanese upland rice cultivars are potential donors of QTL-mediated resistance (Abe et al. 1976). Their resistance is controlled by multiple genes (Fukuoka and Okuno 2001; Higashi and Rabbit polyclonal to KLF4 Kushibuchi 1978; Kato et al. 2002; Miyamoto et al. 2001). For example, the resistance QTLs recognized in cultivar Owarihatamochi have been recognized in three areas, of which has been cloned by map-based cloning, permitting us to solve the long-term problem of linkage pull (Fukuoka et al. 2009). This example is a clear demonstration of the value of validation and good mapping of QTLs for blast resistance. The other two QTLs in Owarihatamochi, on chromosomes 4 (confers moderate resistance, the resistance of elite cultivars carrying can be enhanced by combination with other resistance QTLs. To increase the set of genes for QTL-mediated resistance, extensive genetic studies have investigated QTLs with different magnitudes of effects from several cultivars (Fukuoka and Okuno 2001; Fukuoka et al. 2009; Huang et al. 2011; Jia and Liu 2011; Kato et al. 2002; Liu et al. 2011; Miyamoto et al. 2001; Nguyen et al. 2006; Shi et al. 2010; Suh et al. 2009; Terashima et al. 2008; Wang et al. 1994; Xu et al. 2008; Zenbayashi et al. 2002; Zenbayashi-Sawata et al. 2007). Although the elimination of undesirable characters closely linked to loci of interest is a key factor in the successful transfer of genes to commercial cultivars (Fukuoka et al. 2009), most QTLs have not been delimited in advanced progeny lines. Our goal here was to analyze and from your resistant upland rice cultivar Owarihatamochi was substituted into the genetic background of the vulnerable lowland cultivar Aichiasahi (Fig.?1). Owarihatamochi has a higher level of resistance controlled by multiple QTLs, whereas Aichiasahi which bears the race-specific genes and and region, we crossed sub-CSSLs transporting one or two of the QTLs and selected lines having each combination of pairs or all three by means of marker-assisted selection in order to validate the effects of the combined QTLs. Fig.?2 Genetic linkage map and graphical genotypes of sub-CSSLs around indicate chromosome areas derived from the resistant Owarihatamochi; indicate those derived from the vulnerable Aichiasahi. The locations of … Fig.?3 Physical map and graphical genotypes of sub-CSSLs around and indicate regions derived PKI-587 from the resistant Owarihatamochi; indicate those derived from the vulnerable Aichiasahi. The locations of and region using 192 F2 vegetation of the cross between the CSSL and Aichiasahi using Mapmaker software (Lander et al. 1987). The PROC GLM system of the Statistical Analysis Systems package (SAS Institute Inc.) was used to test variations in the phenotypic ideals among genotypes. PKI-587 Building of bacterial artificial chromosome library, sequencing, and gene prediction Megabase-size rice DNA was prepared from young leaves of Owarihatamochi as explained (Zhang et al. 1995). A bacterial artificial chromosome (BAC) library was constructed by ligation of the megabase DNA with the pIndigoBAC vector (Epicenter) and transformation of BACs into DH10B cells (Invitrogen) (Osoegawa et al. 1998). The library consisted of 20,380 clones with an average place size of 100?kb. The clones comprising the locus were screened using DNA markers and and and and and (between markers and (between and experienced a slightly larger effect than by QTL pyramiding In order to validate the effect of and (D) and PKI-587 one carrying only (E), and selected progeny homozygous for the resistance alleles at two.