Open Access059 Molecular Markers Linked to the Ur-6 Gene Controlling Specific Rust Resistance in Common Bean
Author(s) -
Soon O. Park,
Dermot P. Coyne,
James R. Steadman
Publication year - 2000
Publication title -
hortscience
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.518
H-Index - 90
eISSN - 2327-9834
pISSN - 0018-5345
DOI - 10.21273/hortsci.35.3.398d
Subject(s) - rapd , bulked segregant analysis , phaseolus , biology , rust (programming language) , genetics , germplasm , population , genetic linkage , gene , molecular marker , plant disease resistance , botany , gene mapping , genetic diversity , chromosome , demography , sociology , computer science , programming language
Bean rust, caused by Uromyces appendiculatus , is an important disease of common bean ( Phaseolus vulgaris L.). The objective was to identify RAPD markers linked to the gene ( Ur-6 ) for specific resistance to rust race 51 using bulked segregant analysis in an F 2 segregating population from the common bean cross pinto `Olathe' (resistant to rust) × great northern Nebraska #1 selection 27 (susceptible to rust). A single dominant gene controlling specific resistance to race 51 was hypothesized based on F 2 segregation, and then was confirmed in the F 3 generation. A good fit to a 3:1 ratio for band presence to band absence for each of three markers was observed in 100 F 2 plants. Three RAPD markers were detected in a coupling phase linkage with the Ur-6 gene. Coupling-phase RAPD marker OAB14.600 was the most closely linked to the Ur-6 gene at a distance of 3.5 cM among these markers. No RAPD markers were identified in a repulsion phase linkage with the Ur-6 gene. The RAPD markers linked to the gene for specific rust resistance of Middle American origin detected here, along with other independent rust resistance genes from other germplasm, could be utilized to pyramid multiple genes into a bean cultivar for more durable rust resistance.