Diagnostic value of molecular markers for Lr genes and characterization of leaf rust resistance of German winter wheat cultivars with regard to the stability of vertical resistance

Abstract

Breeding for resistance is an efficient strategy to manage wheat leaf rust caused by Puccinia triticina f. sp. tritici. However, a prerequisite for the directed use of Lr genes in breeding and the detection of new races virulent to these Lr genes is a detailed knowledge on Lr genes present in wheat cultivars. Therefore, respective molecular markers for 18 Lr genes were tested for specificity and used to determine Lr genes in 115 wheat cultivars. Results obtained were compared to available pedigree data. Using respective molecular markers, genes Lr1, Lr10, Lr26, Lr34 and Lr37 were detected, but data were not always in accordance with pedigree data. However, leaf rust scoring data of field trials confirmed the reliability of DNA markers. These reliable marker data facilitated the analyses of the development of virulent leaf rust races from 2002 to 2009 based on released cultivars. A sudden change from low infection rates to susceptibility was observed for Lr1, Lr3, Lr10, Lr13, Lr14, Lr16, Lr26 and Lr37 since 2006. Cultivars carrying several leaf rust resistance genes showed no significant shift to susceptibility except one cultivar which revealed an increasing infection rate at a low level. In summary, it turned out that pedigree data are often not reliable and a detection of Lr genes by diagnostic markers is fundamental to combine Lr genes in cultivars for a durable resistance against leaf rust, and to conduct reliable surveys based on released cultivars, instead of 'Thatcher' NILs.

The virulence spectrum of the wheat leaf rust population analyzed in the Czech Republic from 2002 to 2011

“…High frequency of virulence on Lr2c was also recorded in France (Goyeau et al 2006). A sudden change from avirulence to virulence on Lr1, Lr3a,Lr10,Lr13,Lr14,Lr16,Lr26 and Lr37 since 2006 was described in Germany (Serfling et al 2011). Virulence frequency on Lr1 increased in Russia in the years [2001][2002][2003][2004][2005][2006] in central parts of the country and decreased in the northwestern region (Gultyaeva et al 2000).…”

Characteristics of virulence of Puccinia triticina populations and the potential of the Lr24, Lr25, LrSp genes for spring common wheat breeding in the Southern Ural

“…В настоящее время информативные ПЦР-маркеры подобраны для более 20 Lrгенов. Эти маркеры широко используются в селекционных учреждениях в России и за рубежом (Гайнулин и др., 2007;Serfling et al, 2011;Давоян и др., 2014).…”

Virulence of wheat leaf rust (Puccinia triticina Eriks.) in the years 2013–2015 and resistance of wheat cultivars in Slovakia

“…Goyeau and Lannou (2011) postulated the frequency of Lr10, Lr24, Lr26 and Lr37 using multi-pathotype tests in 275 wheat cultivars grown in France from 1983 to 2007 was 34%, 1%, 7% and 45%, respectively. In the test of Serfling et al (2011) comprising 115 German cultivars, molecular markers were used to determine the presence of Lr10 in 35 cultivars, Lr26 in 14 cultivars, Lr34 in 2 cultivars, Lr37 in 48 cultivars.…”