Genetic analysis and molecular mapping of crown rust resistance in common wheat

Abstract

This is the first report on genetic analysis and genome mapping of major dominant genes for near non-host resistance to barley crown rust ( Puccinia coronata var. hordei ) in common wheat. Barley crown rust, caused by Puccinia coronata var. hordei, primarily occurs on barley (Hordeum vulgare L.) in the Great Plain regions of the United States. However, a few genotypes of common wheat (Triticum aestivum L.) were susceptible to this pathogen among 750 wheat accessions evaluated. To investigate the genetics of crown rust resistance in wheat, a susceptible winter wheat accession PI 350005 was used in crosses with two resistant wheat varieties, Chinese Spring and Chris. Analysis of F1 plants and F2 populations from these two crosses indicated that crown rust resistance is controlled by one and two dominant genes in Chris and Chinese Spring, respectively. To determine the chromosome location of the resistance gene Cr1 in Chris, a set of 21 monosomic lines derived from Chris was used as female parents to cross with a susceptible spring type selection (SSTS35) derived from the PI 350005/Chris cross. Monosomic analysis indicated that Cr1 is located on chromosome 5D in Chris and one of the crown rust resistance genes is located on chromosome 2D in Chinese Spring. The other gene in Chinese Spring is not on 5D and thus is different from Cr1. Molecular linkage analysis and QTL mapping using a population of 136 doubled haploid lines derived from Chris/PI 350005 further positioned Cr1 between SSR markers Xwmc41-2 and Xgdm63 located on the long arm of chromosome 5D. Our study suggests that near non-host resistance to crown rust in these different common wheat genotypes is simply inherited.

Proteomic Analysis of Rice Nonhost Resistance to Puccinia striiformis f. sp. tritici Using Two-Dimensional Electrophoresis

“…Genetic studies demonstrated that NHR in wheat and barley crown rust ( Puccinia coronata var. hordei ) was controlled through one or two dominant genes in wheat accessions Chris and Chinese Spring, respectively [ 33 ]. Niks et al [ 12 ] proposed that nonhost plants, especially near-nonhost, possess multiple R genes corresponding to Avr genes in potential pathogens.…”

Genetic analysis and molecular mapping of resistance to Puccinia striiformis f. sp. pseudo‐hordei in common wheat

“…Previous genetic studies on the resistance to heterologous rust pathogens in wheat, including barley crown rust ( Puccinia coronata var. hordei , Pch) and rye stem rust (Pgs), were either dependent on rare susceptible genotypes or the development of susceptible experimental lines (Sanghi, ; Jin & Steffenson, ; Niu et al ., ). These previous studies and the current study suggest that wheat is an intermediate or near‐nonhost to Pch, Pgs and Psph.…”

Mapping genes in barley for resistance to Puccinia coronata from couch grass and to P. striiformis from brome, wheat and barley

“…In our previous study (Niks et al 2013), we found a few barley accessions that reacted hypersensitively to PcE, and possibly their resistance is due to Rpc1. In wheat, a near-nonhost to the barley crown rust, resistance was reported to be due to one (cv Chris) or two (cv Chinese Spring) dominant major genes for resistance (Niu et al 2014). The resistance found in the present study was quantitative, and we found different QTLs that conferred resistance.…”