Genetic mapping of two powdery mildew resistance genes in einkorn (Triticum monococcum L.) accessions

Abstract

Powdery mildew is a severe foliar disease for wheat and could cause great yield loss in epidemic years. To explore new powdery mildew resistance genes, two einkorn accessions including TA2033 and M80, both resistant to this disease, were studied for the inheritance of resistance. Each accession possessed a single but different dominant resistance gene that was designated as Mlm2033 and Mlm80, respectively. Marker mapping indicated that they are both linked to Xgwm344 on the long arm of chromosome 7A. To establish their genetic relationship with Pm1 on 7AL, five RFLP markers previously reported to co-segregate with Pm1a were converted to STS markers. Three of them detected polymorphism between the mapping parents and were mapped close to Mlm2033 or Mlm80 or both. Xmag2185, the locus determined by the STS marker derived from PSR680, one of the RFLP markers, was placed less than 2 cM away from them. The allelism test indicated that Mlm2033 and Mlm80 are likely allelic to each other. In addition, through comparative and EST mapping, more markers linked to these two genes were identified. The high density mapping of Mlm2033 and Mlm80 will contribute to map-based cloning of the Pm1 locus. The markers for both genes will also facilitate their transfer to wheat.

Study of genetic parameters and association between characters in einkorn genotypes

“…It is very useful and promising plant breeding material for its resistance to disease (rusts, powdery mildew) (1)(2)(3)(4)(5)(6)(7)(8). The crop is suitable for low input systems -organic farmingbecause of its better adaptability in marginal areas (in comparison with other crops) (1,9).…”

Identification and mapping of two powdery mildew resistance genes in Triticum boeoticum L.

“…Molecular markers, however, can be employed for breeding powdery mildew resistant varieties. In the present study, we identified a Yao et al (2007) have also been reported to be allelic to Pm1, based on the markers linked to these genes. Pm37 has been reported to be closely linked to Pm1.…”

“…In order to saturate the regions carrying the powdery mildew resistance genes, primers designed from RFLP probes, MAG1714, MAG2166, MAG2185, MAG1757 and MAG1759, reported to be linked with powdery mildew resistance genes on chromosome 7A (Yao et al 2007), were analysed on the RIL population. In addition, 38 primers designed from ESTs and 20 SSR primers already mapped on the distal half of 7AL (Somers et al 2004) were analysed for parental polymorphism.…”

“…Likewise, genes such as Pm4a, Pm4b,Pm5a,Pm6,Pm16,Pm26,Pm27,Pm30, Pm31 and Pm33 have been transferred from tetraploid wheat (McIntosh et al 2008). Srnic et al (2005) reported the identification of two dominant resistance genes from T. monococcum L. and Triticum timopheevii L. Yao et al (2007) identified two new alleles of Pm1 from two different accessions of T. monococcum. Xu et al (2008) mapped and introgressed a recessive powdery mildew resistance gene from T. monococcum on chromosome 5AL.…”

Molecular detection of disease resistance genes to powdery mildew (Blumeria graminis f. sp. tritici) in wheat (Triticum aestivum) cultivars

“…Currently, the yield losses range from 13 to 34% under high infestation in the field but during epidemic seasons, the disease can cause up to 50% yield loss (Yao et al, 2007;Zhang et al, 2008;Li et al, 2011;Alam et al, 2013;Quijano et al, 2015;Yu et al, 2015). The shift in pathogenic virulence structures range from the southwest and the southeast coastal regions of China to almost all the wheat growing areas throughout the country and the damage exceeds any other known wheat disease (Liu and Shao, 1994;Luo et al, 2009;Cao et al, 2013;Zhao et al, 2013;Shen et al, 2015).…”