U.S. Department of Agriculture: Agricultural Research Service, Lincoln, Nebraska

 

Genotyping tools and resources to assess peanut germplasm: Smut-resistant landraces as a case study

Alicia N. Massa, USDA ARS National Peanut Research Laboratory
Marina Bressano, Universidad Nacional de Córdoba
Juan H. Soave, Criadero El Carmen
Mario I. Buteler, Criadero El Carmen
Guillermo Seijo, Instituto de Botanica del Nordeste
Victor S. Sobolev, USDA ARS National Peanut Research Laboratory
Valerie A. Orner, USDA ARS National Peanut Research Laboratory
Claudio Oddino, Criadero El Carmen
Sara J. Soave, Criadero El Carmen
Paola C. Faustinelli, USDA ARS National Peanut Research Laboratory
Francisco J. de Blas, Instituto Multidisciplinario de Biología Vegetal
Marshall C. Lamb, USDA ARS National Peanut Research Laboratory
Renee S. Arias, USDA ARS National Peanut Research Laboratory

Document Type Article

Abstract

Peanut smut caused by Thecaphora frezii is a severe fungal disease currently endemic to Argentina and Brazil. The identification of smut resistant germplasm is crucial in view of the potential risk of a global spread. In a recent study, we reported new sources of smut resistance and demonstrated its introgression into elite peanut cultivars. Here, we revisited one of these sources (line I0322) to verify its presence in the U.S. peanut germplasm collection and to identify single nucleotide polymorphisms (SNPs) potentially associated with resistance. Five accessions of Arachis hypogaea subsp. fastigiata from the U.S. peanut collection, along with the resistant source and derived inbred lines were genotyped with a 48K SNP peanut array. A recently developed SNP genotyping platform called RNase H2 enzyme-based amplification (rhAmp) was further applied to validate selected SNPs in a larger number of individuals per accession. More than 14,000 SNPs and nine rhAmp assays confirmed the presence of a germplasm in the U.S. peanut collection that is 98.6% identical (P < 0.01, bootstrap t-test) to the resistant line I0322. We report this germplasm with accompanying genetic information, genotyping data, and diagnostic SNP markers.