QTL Conferring Fusarium Crown Rot Resistance in the Elite Bread Wheat Variety EGA Wylie

Abstract

Fusarium crown rot (FCR) is one of the most damaging cereal diseases in semi-arid regions worldwide. The genetics of FCR resistance in the bread wheat (Triticum eastivum L.) variety EGA Wylie, the most resistant commercial variety available, was studied by QTL mapping. Three populations of recombinant inbred lines were developed with this elite variety as the resistant parent. Four QTL conferring FCR resistance were detected and resistance alleles of all of them were derived from the resistant parent EGA Wylie. One of these loci was located on the short arm of chromosome 5D (designated as Qcrs.cpi-5D). This QTL explains up to 31.1% of the phenotypic variance with an LOD value of 9.6. The second locus was located on the long arm of chromosome 2D (designated as Qcrs.cpi-2D) and explained up to 20.2% of the phenotypic variance with an LOD value of 4.5. Significant effects of both Qcrs.cpi-5D and Qcrs.cpi-2D were detected in each of the three populations assessed. Another two QTL (designated as Qcrs.cpi-4B.1 and Qcrs.cpi-4B.2, respectively) were located on the short arm of chromosome 4B. These two QTL explained up to 16.9% and 18.8% of phenotypic variance, respectively. However, significant effects of Qcrs.cpi-4B.1 and Qcrs.cpi-4B.2 were not detected when the effects of plant height was accounted for by covariance analysis. The elite characteristics of this commercial variety should facilitate the incorporation of the resistance loci it contains into breeding programs.

Histological Evidence for Different Spread of Fusarium crown rot in Barley Genotypes with Different Heights

“…; Zheng et al. ). However, it is not clear whether the different FCR severities observed between tall and dwarf genotypes were due to different susceptibility of genotypes with different heights to the same concentration of the pathogen or the shorter genotypes could indeed slow down the development of FCR.…”

“…; Zheng et al. ). Further studies based on near isogenic lines (NILs) for various reduced height ( Rht ) genes confirmed the initial observation from the use of segregating populations that dwarf isolines indeed showed reduced symptom of the disease in wheat (Liu et al.…”

“…; Zheng et al. . These studies showed that some loci conferring resistance to FCR co‐locate with that for plant height (Li et al.…”

“…Growing resistant varieties is recognized as an important component in effectively managing FCR. As part of the efforts to enhance selection efficiency in breeding FCR-resistant varieties, several QTL conferring resistance have been detected in recent years in both barley (Li et al 2009;Chen et al 2013a,b) and wheat (Bovill et al 2006;Li et al 2010;Ma et al 2010;Zheng et al 2014. These studies showed that some loci conferring resistance to FCR co-locate with that for plant height (Li et al 2009;Chen et al 2013b;Zheng et al 2014).…”

Breeding wheat for drought adaptation: Development of selection tools for root architectural traits

“…Drysdale is an Australian cultivar with superior transpiration efficiency (Condon et al, 2004;Tausz-Posch et al, 2012). SB062 is a breeding line developed in the 'Physiological Wylie has high levels of Fusarium crown rot resistance and black point tolerance (Queensland Wheat Variety Guide, 2014;Zheng et al, 2014). The Australian cultivar Westonia was selected for acid soil tolerance, and tolerance to manganese and aluminium toxicities in soil (Tang et al, 2003;Khabaz-Saberi et al, 2010).…”