Validation and Interaction of the Soybean Mosaic Virus Lethal Necrosis Allele, Rsv1-n, in PI 507389

• Published in: Crop science Vol. 49; no. 4; pp. 1277 - 1283
• Main Authors: Tucker, D.M, Saghai Maroof, M.A, Jeong, S.C, Buss, G.R, Tolin, S.A
• Format: Journal Article
• Language: English
• Published: Madison Crop Science Society of America 01.07.2009; American Society of Agronomy
• Subjects: Agronomy. Soil science and plant productions; alleles; Biological and medical sciences; Crop diseases; disease resistance; dominant genes; Fundamental and applied biological sciences. Psychology; gene interaction; gene pyramiding; Genes; genetic resistance; genetic variation; Genetics; Genetics and breeding of economic plants; Genomics; genotype; Genotype & phenotype; Glycine max; introgression; mortality; necrosis; plant diseases and disorders; resistance genes; signs and symptoms (plants); Soybean mosaic virus; Soybeans; strain differences; Validation; Soybean mosaic virus; Plant pathogen; Lethal character; Glycine max; Necrosis; Virus; Grain legume; Allele; Microorganism resistance; Leguminosae; Dicotyledones; Angiospermae; Spermatophyta; Potyvirus; Potyviridae
• ISSN: 0011-183X; 1435-0653
• DOI: 10.2135/cropsci2008.08.0477

Soybean mosaic virus (SMV) is the causal agent of a commonly occurring disease of soybean [Glycine max (L.) Merr.] that can be effectively controlled through the deployment of single, dominant genes known as Rsv genes, which confer resistance to different strains of SMV. The Rsv1-n allele in PI 507389 conditions a lethal necrosis (LN) reaction on inoculation with specific SMV strains, including SMV-G1, -G5, and -G6. The objective of the current study was to examine effects of the Rsv1-n allele introgressed into the susceptible genotype 'Essex' background alone or in combination with either Rsv3 or Rsv4 resistance genes by inoculation with six different SMV strains. Presence of Rsv1-n and its LN as well as severe mosaic reactions to the strains tested were masked when the gene was pyramided with Rsv3 and Rsv4. Thus in some cases, the LN-causing gene may go undetected in breeding populations. Pyramided isolines containing Rsv1-n and Rsv4 together were susceptible to SMV-G6, displaying a mosaic reaction, although Rsv4 alone confers resistance against all known strains. This study demonstrates the importance of selecting against the Rsv1-n allele to prevent its introduction into breeding programs.