|Miklas, Phillip - Phil|
Submitted to: Journal of the American Society for Horticultural Science
Publication Type: Peer reviewed journal
Publication Acceptance Date: 6/1/2007
Publication Date: 10/1/2007
Citation: Osorno, J. M., C. G. Muñoz, J. S. Beaver, F. H. Ferwerda, M. J. Bassett, P. N. Miklas, T. Olczyk, and B. Bussey. 2007. Two genes from Phaseolus coccineus L. confer resistance to Bean golden yellow mosaic virus in common bean. J. Amer. Soc. Hort. Sci. 132:530-533. Interpretive Summary: This paper describes the identification and characterization of two new genes for resistance to Bean golden yellow mosaic virus (BGYMV). This viral disease is a major problem for dry and snap beans grown in the sub-tropics and tropics. Genetic resistance has been the only effective means for controlling this disease. Only a few genes have been discovered to date and they are vulnerable to being overcome by new strains of the pathogen. ARS scientists conducted the initial interspecific crosses and early generation breeding and pathogen testing to develop stable dry bean lines with the BGYMV resistance introgressed from Scarlet Runner Bean. University of Puerto Rico and Florida researchers conducted the inheritance studies. These newly discovered and characterized genes will shore up the arsenal of genes for combating BGYMV and will lead to develoment of dry bean cultivars with more effective and durable resistance.
Technical Abstract: Bean golden yellow mosaic virus (BGYMV), caused by a whitefly (Bemisia spp.) transmitted geminivirus, is an important disease that can limit common bean (Phaseolus vulgaris L.) production in Central America, the Caribbean and southern Florida. Only a few genes are currently deployed in BGYMV resistant common bean cultivars. The identification of novel sources of resistance would help bean breeders broaden the genetic base of resistance to this important virus. Phaseolus coccineus L. germplasm accession G35172 was found by CIAT scientists to be resistant to BGYMV. Populations derived from an interspecific cross between P. vulgaris and P. coccineus were evaluated to study the inheritance of resistance to BGYMV. Segregation ratios of F2 plants and other populations suggest that BGYMV resistance from P. coccineus is controlled by two genes. A recessive gene, with the proposed symbol bgm-3, confers resistance to leaf chlorosis and a dominant gene, with the proposed name Bgp-2, prevents pod deformation in the presence of BGYMV. Results from allelism tests with previously reported BGYMV resistance genes, bgm, bgm-2 and Bgp, and the absence of the SR-2 SCAR marker for bgm support the hypothesis that bgm-3 and Bgp-2 are different genes for BGYMV resistance.