Functional Codominant Marker for Selecting the Fw Gene Conferring Resistance to Fusarium Wilt Race 1 in Pea

Fusarium oxysporum f. sp. pisi (Fop) is a major soil-borne pathogen and the causal agent of Fusarium wilt of pea (Pisum sativum L.), resulting in significant yield losses. Resistant cultivars have become the most effective method for controlling this fungal disease. The gene controlling resistance to F. oxysporum race 1 in pea, Fw, is located on linkage group (LG) III and widely used in breeding programs. Although this locus is routinely used for developing resistant cultivars, a robust codominant DNA marker for selection of the Fw gene is not currently available. We developed a breeder-friendly functional codominant cleaved amplified polymorphic sequence (CAPS) marker, THO, which can be used in pea breeding programs for selection of resistance to F. oxysporum race 1. Using this marker, we were able to select pea lines with 96 to 98% accuracy in mapping populations and 94% accuracy in advanced pea breeding lines. This marker, in combination with other gene based markers (AnMtL6, Mt5_56, and PRX1TRAP13) developed from conserved sequences of closely related legume species, lays the foundation for candidate gene identification through comparative mapping.