Phenotyping of a RILs population derived from a synthetic amphidiploid for peanut

DE BLAS, F.; SOAVE, S.; TORRES, L.; ODDINO, C.

Brisbane

Congreso; Advances in Arachis through Genomics and Biotechnology (AAGB) 2015; 2015

Peanut Genome Initiative

Peanut smut (Thecaphora frezii) is causing major damages to the peanut crop in Argentina, particularly in C¨®rdoba the main producing region. Criadero El Carmen has developed a 94 recombinant inbreed lines population derived by single seed descent from the cross of the synthetic amphidiploid JS.S*-1806¡ª[(A. correntina x A. cardenasi) x A. batizocoi]4x¡ªand the high oleic elite peanut line JS.17304-7-B. The parent JS.S*-1806 has been tested as immune to the smut while the A. hypogea parent is highly susceptible as all cultivars used in Argentina. The objective was phenotyping the RILs population for peanut smut resistance to study the inheritance of the trait for characterizing its genetic architecture and developing a system of molecular markers to assist in the introgression of resistance genes from wild Arachis species used. In 2014/2015 season, the 94 RILs and its parents were planted in a managed environment fivefold smut teliospore concentration usually find in any peanut crop field in the region. At the end of the season all pods were evaluated for the incidence of peanut smut¡ª% of infected pods¡ªand disease severity measured on a 0 to 4 scale. Statistical analysis was based on a mixed model with genotypes as fixed effects. The DGC test discriminated (p¡Ü0,05) three genotypes groups: (A) comprising the susceptible parent, showing a high to medium disease incidence; (B) showing a medium incidence level; and (C) with a very low level¡ªbelow 1% of incidence¡ªor completely sound, equal to the immune amphidiploid.