Pathotype characterization of isolates collected from pea breeding nurseries.

Introduction: Drechsler is an oomycete pathogen that affects legume crops, causing root rot, a severe disease of peas ( L.) worldwide. While significant research progress has been made in breeding pea-resistant varieties, there is still a need for a deeper understanding of the diversity of pathogen populations present in breeding nurseries located in various legume-growing regions around the world.

Genetic and Pathogenicity Diversity of Populations From Pea-Growing Regions in France.

is an oomycete pathogen with a broad host-range on legumes that causes devastating root rot disease in many pea-growing countries and especially in France. Genetic resistance is a promising way to manage the disease since consistent QTL controlling partial resistance have been identified in near isogenic lines of pea. However, there are still no resistant pea varieties cultivated in France.

Single and multiple resistance QTL delay symptom appearance and slow down root colonization by Aphanomyces euteiches in pea near isogenic lines.

Background: Understanding the effects of resistance QTL on pathogen development cycle is an important issue for the creation of QTL combination strategies to durably increase disease resistance in plants. The oomycete pathogen Aphanomyces euteiches, causing root rot disease, is one of the major factors limiting the pea crop in the main producing countries. No commercial resistant varieties are currently available in Europe.

Genome-wide association mapping of partial resistance to Aphanomyces euteiches in pea.

Background: Genome-wide association (GWA) mapping has recently emerged as a valuable approach for refining the genetic basis of polygenic resistance to plant diseases, which are increasingly used in integrated strategies for durable crop protection. Aphanomyces euteiches is a soil-borne pathogen of pea and other legumes worldwide, which causes yield-damaging root rot. Linkage mapping studies reported quantitative trait loci (QTL) controlling resistance to A.

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

Marker-assisted backcrossing was used to generate pea NILs carrying individual or combined resistance alleles at main Aphanomyces resistance QTL. The effects of several QTL were successfully validated depending on genetic backgrounds. Quantitative trait loci (QTL) validation is an important and often overlooked step before subsequent research in QTL cloning or marker-assisted breeding for disease resistance in plants.

A Sensitive Assay for Rapid Detection and Quantification of Aphanomyces euteiches in Soil.

Aphanomyces euteiches is a widespread oomycete pathogen causing root rot in a wide range of leguminous crops. Losses can reach up to 100% for pea culture and there is currently no registered pesticide for its control. Crop management remains the most efficient tool to control root rot, and avoidance of infested soil seems to be the optimal solution.

A complex genetic network involving a broad-spectrum locus and strain-specific loci controls resistance to different pathotypes of Aphanomyces euteiches in Medicago truncatula.

A higher understanding of genetic and genomic bases of partial resistance in plants and their diversity regarding pathogen variability is required for a more durable management of resistance genetic factors in sustainable cropping systems. In this study, we investigated the diversity of genetic factors involved in partial resistance to Aphanomyces euteiches, a very damaging pathogen on pea and alfalfa, in Medicago truncatula. A mapping population of 178 recombinant inbred lines, from the cross F83005.

Development of a molecular method to detect and quantify Aphanomyces euteiches in soil.

A real-time PCR assay using 136F/211R primers and 161T TaqMan probe for the detection and quantification of Aphanomyces euteiches in soil is presented. The specificity of primers was tested on 105 different A. euteiches isolates, mainly from France.