Development and Phenotyping of Recombinant Inbred Line (RIL) Populations for Peanut (Arachis hypogaea)

ABSTRACT The identification of molecular markers for economically significant traits should greatly improve the speed and efficiency of all peanut (Arachis hypogaea L.) breeding programs. Development and phenotypic evaluation of recombinant inbred line (RIL) populations of peanut, along with molecular genotyping, will be essential for association of markers with traits. The primary objectives of this research were to develop 16 structured RIL populations that can be used by the peanut research community, and to begin high-resolution phenotyping of these populations. Crosses were made using a 2 by 8 (common by unique) factorial nested association mapping design. Parents were selected to attempt to maximize genetic diversity while meeting practical breeding objectives. First, two modern runner cultivars (Tifrunner and Florida-07) were selected as common parents because runner cultivars account for about 80% of the production in the U.S. Second, the eight unique parents were selected to supply diversity across market classes and botanical varieties and are donors of favorable alleles for enhancing drought tolerance and resistance to most important disease of peanut in the U.S. The eight unique parents are N08082olJCT (a Bailey derived high oleic breeding line), C76-16, NC 3033, SPT 06-06, SSD 6 (PI 576638), OLin, New Mexico Valencia A, and Florunner. The 16 populations were advanced using summer and winter nurseries. Input from multiple disciplines has resulted in a prioritized list of populations and traits that should be examined, and seed increase has begun to provide the community with material for extensive phenotyping. In-depth phenotyping and genotyping of these populations should result in markers that can be deployed by breeding programs for the development of improved cultivars.