Reaction of genotypes from several species of grain and forage legumes to infection with a French pea isolate of the oomycete Aphanomyces euteiches

Abstract

The susceptibility/resistance to Aphanomyces euteiches of various genotypes (cultivars and breeding lines) of several grain legume species was assessed in controlled conditions. A total of 279 genotypes from the major grain legumes grown in temperate climates (faba bean, chickpea, lentil, lupin and common vetch) and three other legumes frequently cultivated in France (French bean, clover and alfalfa) were screened with one pea-infecting isolate from France. Four different categories of susceptibility/resistance were identified among the legume species/cultivars tested with the pea A. euteiches isolate: (1) susceptible legume species (lentil, alfalfa, French bean) among which low levels of partial resistance was observed; (2) legume species including susceptible genotypes and genotypes with high levels of resistance (common vetch, faba bean and clover), (3) species with a very high level of resistance (chickpea) and (4) species displaying no symptoms (lupin). It is therefore important to consider pathogen-species and pathogengenotype interactions when defining the host specificity of A. euteiches and considering the possible role of different legume species in increasing or decreasing the soil inoculum potential.

QTL meta-analysis provides a comprehensive view of loci controlling partial resistance to Aphanomyces euteichesin four sources of resistance in pea

“…Analysis of the DSP × 90–2131 RIL resistance data in controlled conditions showed that the five pea lines used as controls ranked as expected for root rot index (RRI) scores with all but one of the six A. euteiches strains, confirming the strain pathotypes as described in [51] and [52] (Additional file 1). RRI scores in the DSP × 90–2131 RILs showed highly significant genotypic and block effects ( P  < 0.001) for each strain with the exception of Ae85.…”

A wide range of cultivated legume species act as alternative hosts for the pea aschochyta blight fungus, Didymella pinodes

“…As was recently shown by Moussart et al . (), variation in disease response can be significant at both the host species level as well as the host cultivar level. In the current study, cultivars from five different legume species were used to characterize the behaviour of D. pinodes isolates sampled from pea.…”

Validation of QTL for resistance to Aphanomyces euteiches in different pea genetic backgrounds using near-isogenic lines

“…Zoospores were produced as previously described by Moussart et al (2001). Seven days after inoculation, disease severity (DS) on each uprooted and washed plant was assessed according to a 0 to 5 scoring scale (Moussart et al 2008) (0 = no symptoms; 1 = traces of discoloration on the roots (<25 %); 2 = discoloration of 25-50 % of the roots; 3 = discoloration of 50-75 % of the roots; 4 = discoloration of >75 % of the roots; 5 = plant dead). 2 Genetic map positions of the seven main Aphanomyces resistance QTL and markers used in the Marker-assisted backcrossing scheme for NIL production.…”

“…In Europe, the disease has spread since the 1990s due to the intensification of pea production and can lead to total devastation of the crop in infested fields (Didelot and Chaillet 1995). Symptoms of the disease are translucent lesions on the rootlets, which evolve into brown rot affecting the entire root system up to the epicotyl (Moussart et al 2008). Above ground, the disease causes stunted seedlings, yellow leaves and even dead plants.…”