Quantitative trait loci for lodging resistance, plant height and partial resistance to mycosphaerella blight in field pea (Pisum sativum L.)

Abstract

With the development of genetic maps and the identification of the most-likely positions of quantitative trait loci (QTLs) on these maps, molecular markers for lodging resistance can be identified. Consequently, marker-assisted selection (MAS) has the potential to improve the efficiency of selection for lodging resistance in a breeding program. This study was conducted to identify genetic loci associated with lodging resistance, plant height and reaction to mycosphaerella blight in pea. A population consisting of 88 recombinant inbred lines (RILs) was developed from a cross between Carneval and MP1401. The RILs were evaluated in 11 environments across the provinces of Manitoba, Saskatchewan and Alberta, Canada in 1998, 1999 and 2000. One hundred and ninety two amplified fragment length polymorphism (AFLP) markers, 13 random amplified polymorphic DNA (RAPD) markers and one sequence tagged site (STS) marker were assigned to ten linkage groups (LGs) that covered 1,274 centi Morgans (cM) of the pea genome. Six of these LGs were aligned with the previous pea map. Two QTLs were identified for lodging resistance that collectively explained 58% of the total phenotypic variation in the mean environment. Three QTLs were identified each for plant height and resistance to mycosphaerella blight, which accounted for 65% and 36% of the total phenotypic variation, respectively, in the mean environment. These QTLs were relatively consistent across environments. The AFLP marker that was associated with the major locus for lodging resistance was converted into the sequence-characterized amplified-region (SCAR) marker. The presence or absence of the SCAR marker corresponded well with the lodging reaction of 50 commercial pea varieties.

Molecular detection of QTL controlling plant height components in a doubled haploid barley population

“…Lodging is a common problem in barley and in some situations can reduce the grain yield of barley by 28-65% (Sisler and Olsen, 1951;Stanca et al, 1979;Jedel and Helm, 1991;Sameri et al, 2009). When a cereal crop suffers extensive lodging, fungal disease development on the spikes is increased, and the size and weight of grain and the efficiency of mechanical harvesting are drastically reduced (Stanca et al, 1979;Tar'an et al, 2003;Sameri et al, 2009). The tendency to lodge is a function of stem strength, so a dwarfing and semi-dwarfing plant minimizes the risk of lodging, as well as increasing the harvest index (Bezant et al, 1996;Hellewell et al, 2000).…”

Resistance to ascochyta blights of cool season food legumes

“…The genetics of resistance to ascochyta blight in peas indicate a multiple gene system with some dominance and additive genetic effects (Wroth 1999). Estimates of quantitative trait loci (QTL) for resistance to ascochyta blight have ranged from three (Tar'an et al 2003) to 13 (Timmerman-Vaughan et al 2004) (Table 1). The complex nature of resistance, as indicated by the number of QTL that have been estimated, presents a challenge to breeders and the prospect of making use of marker assisted selection for ascochyta blight resistance in peas.…”

Pea

“…The first QTL reported was that for seed weight (TimmermanVaughn et al 1996) (Valderrama et al 2004), and resistance to Aphanomyces euteiches (Pilet-Nayel et al 2002) and Mycosphaerella pinodes (TimmermanVaughn et al 2002;Tar'an et al 2003;Prioul et al 2004).…”

“…Three laboratories have investigated resistance mechanisms and reported QTLs for resistance to these pathogens (Timmerman-Vaughn et al 2002;Tar'an et al 2003;Prioul et al 2004). Timmerman-Vaughn (2002) LGs II, IV and VI.…”

“…The seed-protein-content QTLs were located on LGs III, VI and an unlinked LG A each explaining 30, 16, and 11% of the variation, respectively. Plant height QTLs were identified by Tar'an et al (2003) and Prioul et al (2004), andPrioul et al (2004) identified QTLs for plant height on LG II, III and VII while Tar'an et al (2003) identified QTLs on LG III and two unlinked LGs, C and D. The QTLs on LG III accounted for 57 and 63% of the variation for plant height in each of the reports, respectively.…”