Identification and mapping of leaf, stem and stripe rust resistance quantitative trait loci and their interactions in durum wheat

Abstract

Leaf rust (Puccinia triticina Eriks.), stripe rust (Puccinia striiformis f. tritici Eriks.) and stem rust (Puccinia graminis f. sp. tritici) cause major production losses in durum wheat (Triticum turgidum L. var. durum). The objective of this research was to identify and map leaf, stripe and stem rust resistance loci from the French cultivar Sachem and Canadian cultivar Strongfield. A doubled haploid population from Sachem/Strongfield and parents were phenotyped for seedling reaction to leaf rust races BBG/BN and BBG/BP and adult plant response was determined in three field rust nurseries near El Batan, Obregon and Toluca, Mexico. Stripe rust response was recorded in 2009 and 2011 nurseries near Toluca and near Njoro, Kenya in 2010. Response to stem rust was recorded in field nurseries near Njoro, Kenya, in 2010 and 2011. Sachem was resistant to leaf, stripe and stem rust. A major leaf rust quantitative trait locus (QTL) was identified on chromosome 7B at Xgwm146 in Sachem. In the same region on 7B, a stripe rust QTL was identified in Strongfield. Leaf and stripe rust QTL around DArT marker wPt3451 were identified on chromosome 1B. On chromosome 2B, a significant leaf rust QTL was detected conferred by Strongfield, and at the same QTL, a Yr gene derived from Sachem conferred resistance. Significant stem rust resistance QTL were detected on chromosome 4B. Consistent interactions among loci for resistance to each rust type across nurseries were detected, especially for leaf rust QTL on 7B. Sachem and Strongfield offer useful sources of rust resistance genes for durum rust breeding.

QTL mapping of adult plant resistance to Ug99 stem rust in the spring wheat population RB07/MN06113-8

“…Other loci on chromosome 1A that are significantly associated with resistance to African stem rust races have been reported by Rouse et al (2014b) in 'Thatcher' wheat (QTL QSr.cdl-1AL), Bhavani et al (2011) in the CIMMYT biparental population PBW343/Kingbird (QTL between the markers wPt-0128 and wPt-734078), Yu et al (2012) in CIMMYT's winter wheat breeding germplasm, Pozniak et al (2008) in a durum wheat (Triticum durum Desf.) association mapping panel, and Singh et al (2013b) in the durum wheat population Sachem/Strongfield. The only QTL located on chromosome 2D providing APR to the African stem rust races was reported by Bhavani et al (2011) in the CIMMYT population PBW343/ Kiritati, which is located 14 cM from the position of QSr.umn-2D.…”

Adult plant resistance of selected Kenyan wheat cultivars to leaf rust and stem rust diseases

“…It will be interesting to see if other new APR genes for stem rust are also responsible for leaf rust resistance observed in the current study. This is highly possible as most of these APR genes have pleiotropic effects, and also do not confer adequate levels of resistance when present singly (Kolmer 1996;Singh et al 2013;Silva et al 2015). The nested bi-parental population developed using the eight Kenyan cultivars in the backgrounds of Kariega and Morocco will therefore provide a powerful tool for identifying the 'unconfirmed or unknown' APR genes or QTLs controlling resistance to leaf rust and stem rust and possibly other economically important traits.…”

Screening For Resistance Against Rust Diseases In Advanced Wheat (Triticum Aestivum L.) Genotypes

“…The bi-parental mapping populations have recently been used to relate phenotype driven knowledge to genotypic results acquired through molecular markers in order to determine the numeral and locality of the resistance loci on the chromosome. 19,20 Disease reactions for the cereal rusts can be evaluated by either qualitative or quantitative manners, or both combined. Wheat is highly affected by three common rusts; stem rust (Puccinia graminis Pers.…”