Location: Crop Genetics and Breeding ResearchTitle: Quantitative trait loci sequencing-derived molecular markers for selection of stem rot resistance in peanut
|CUI, RENJIE - University Of Georgia|
|CLEVENGER, JOSH - Mars, Inc|
|CHU, YE - University Of Georgia|
|BRENNEMAN, TIMOTHY - University Of Georgia|
|ISLEIB, T - North Carolina State University|
|Holbrook, Carl - Corley|
|OZIAS-AKINS, P - University Of Georgia|
Submitted to: Crop Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/7/2020
Publication Date: 5/28/2020
Citation: Cui, R., Clevenger, J., Chu, Y., Brenneman, T., Isleib, T.G., Holbrook Jr, C.C., Ozias-Akins, P. 2020. Quantitative trait loci sequencing-derived molecular markers for selection of stem rot resistance in peanut. Crop Science. 60:2008-2018. https://doi.org/10.1002/csc2.20047.
Interpretive Summary: Marker assisted selection (MAS) can be used to improve the efficiency and effectiveness of developing new peanut varieties. Genetic marker linked to important traits are needed before MAS can be implemented. Stem rot is one of the most damaging disease of peanut with regards to both cost of control and yield loss. We genotyped and phenotyped a population that was segregating for resistance to stem rot to identify two genetic markers linked to resistance. These markers were then validated in a blind selection test by selecting only with markers in a part of the population not used for initial analysis. Resistance to stem rot is a highly complex and quantitative trait. These genetic marker will allow breeders to use MAS to more effectively and efficiently develop peanut varieties with resistance to stem rot.
Technical Abstract: Developing markers linked to key traits has been a focus of peanut genomics in the post-genome era. Multiple disease resistant traits have been found to be qualitative and controlled by major quantitative trait loci (QTL) or even single genes. Southern stem rot (stem rot in short) is a devastating disease of peanut caused by the fungus Sclerotium rolfsii. It has been one of the most damaging diseases of peanut with regard to both cost of control and yield loss in the southeastern United States for the last decade. The disease is initiated annually from sclerotium in the soil. The nonuniform distribution of these propagules leads to the nonuniform development of disease, which makes phenotyping and genetic mapping of resistance difficult. Here we report the mapping of two QTL regions controlling stem rot resistance in peanut. Using careful field evaluation, resistant and susceptible bulks were identified from a recombinant inbred line (RIL) populations and subjected to QTL sequencing (QTL-seq). Developed SNP markers linked to the QTL were validated in a blind selection test by selecting only with markers in a part of the population not used for initial analysis. The lines selected for bulk sequencing also were shown to have strong separation for resistance in an independent field experiment. This work not only delivers markers for marker assisted selection (MAS) for an important disease in peanut, but shows that QTL-seq can work effectively even when considering highly complex, and quantitative traits.