|Pilet-Nayel, Marie-Laure - INRA-UNIP, UMR FRANCE|
|Kraft, John - USDA-ARS, RETIRED|
|Mcgee, Rebecca - PILLSBURY CO., MN|
|Baranger, Alain - INRA-UNIP,UMR FRANCE|
Submitted to: European Conference on Grain Legumes Proceedings
Publication Type: Proceedings
Publication Acceptance Date: January 15, 2002
Publication Date: N/A
Interpretive Summary: We carried out a Quantitative Trait Loci (QTL) mapping study in pea for aphanomyces root rot resistance assessed under field conditions over two years and two locations in the United States. A major QTL, explaining up to 39 percent of the observed resistance variation was identified and could be useful in marker-assisted selection in applied breeding programs.
Technical Abstract: Aphanomyces root rot, caused by Aphanomyces euteiches is one of the most destructive diseases of pea (Pisum sativum L.) worldwide. It was first reported in the 1920's in the United States. In Europe, it was rediscovered in the 1980's, causing heavy losses in many pea producing areas. No efficient chemicals are available to control the disease. Prediction tests have been developed to identify the fungus in infected soils. Since the 1950's, breeding for Aphanomyces resistance in pea has been difficult due to: a) the low level of resistance available; b) the polygenic inheritance of the resistance; c) linkage between resistance and three dominant, horticultural undesirable alleles that control node length, flower color and hilum color; d) variability in disease reaction tests and interaction with other root invading pathogens under field conditions; and, e) variability in the pathogen. In order to assists breeding for A. euteiches resistance and to better understand genetics of quantiative resistance, this study aimed to: i) identify Quantitative Trait Loci (QTL) for field Aphanomyces root rot resistance and ii) assess ATL consistency for several resistance criteria over two years at two locations in the United States.