|Riley, Ronald - NOVARTIS SEED COMPANY|
|Kelly, James - MICHIGAN STATE UNIVERSITY|
Submitted to: Euphytica
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: October 1, 1999
Publication Date: April 1, 2000
Citation: MIKLAS, P.N., LARSEN, R.C., RILEY, R., KELLY, J.D. POTENTIAL MARKER-ASSISTED SELECTION FOR BC-1 2 RESISTANCE TO BEAN COMMON MOSAIC POTYVIRUS IN COMMON BEAN.. EUPHYTICA, 116:211-219. 2000. Interpretive Summary: Bean common mosaic is a seed borne virus which plagues dry and snap bean production worldwide. It is a major problem in the Pacific Northwest and California where bean seed production is concentrated. Many fields grown for seed production are rejected each year due to infection by this virus. Genetic resistance is the only effective control measure. The most sustainable resistance is obtained with combinations of resistance genes. Markers linked with these genes would help breeders to obtain combined resistance. We have identified a marker linked to a resistance gene. The marker will be useful for obtained more sustainable resistance to this virus. Improved resistance will reduce yield loss caused by this virus worldwide and make it easier for growers in the Pacific Northwest and California to produce virus-free seed.
Technical Abstract: In common bean, the most effective strategy for broad spectrum control of the bean common mosaic virus disease is to combine I, bc-u, bc-12, bc-22, and bc-3 genes. We describe the use of near-isogenic lines and bulked segregant analysis to identify a marker tightly linked with the bc-12 gene. The recessive bc-12 gene conditions resistance to specific strains of bean common mosaic virus and bean common mosaic necrosis virus and is masked by the bc-22 and bc-3 genes. We identified a RAPD marker completely linked (0 recombinants) with bc- 12, as examined by 72 F3 progeny generated from a cross between the contrasting near isogenic lines (I + bc-1 / I + bc-12). To facilitate marker-assisted selection of bc-12 across breeding programs, the RAPD was converted to a SCAR marker, designated SBD51300. Tight linkage (0 recombinants) was confirmed in a second population of 58 F2 progeny co-segregating for SBD51300 and bc-12 gene from a different source. Based on a survey of 130 genotype, the SCAR will be useful for MAS of bc-12 in most beans of Middle American origin and snap beans, but will have very limited utility in the case of kidney and cranberry beans. The SBD51300 marker mapped on linkage group B3, revealing independence of bc-12 from the I gene on B2 and bc-3 gene on B6, which supports the opportunity to readily combine genes for broad spectrum and pyramided resistance to bean common mosaic potyviruses in a single bean cultivar.