Location: Crop Genetics and Breeding ResearchTitle: Major seed size QTL on chromosomes A05 of peanut (Arachis hypogaea) is conserved in the U.S. minicore germplasm collection
|CHU, Y - University Of Georgia|
|CHEE, P - University Of Georgia|
|ISLEIB, T - North Carolina State University|
|Holbrook, Carl - Corley|
|OZIAS-AKINS, P - University Of Georgia|
Submitted to: Molecular Breeding
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/10/2019
Publication Date: 12/20/2019
Citation: Chu, Y., Chee, P., Isleib, T.G., Holbrook Jr, C.C., Ozias-Akins, P. 2019. Major seed size QTL on chromosomes A05 of peanut (Arachis hypogaea) is conserved in the U.S. minicore germplasm collection. Molecular Breeding. 40(6):1-16. https://doi.org/10.1007/s11032-019-1082-4.
Interpretive Summary: Pod and seed size are important characteristics for the peanut industry. The object of this study was to attempt to identify genetic markers for pod and seed size. A recombinant inbred line mapping population from a cross of Florida-07 by GP-NC WS 16 was used to determine the genetic regions associated with pod and seed size. A major QTL was identified on chromosome A05 which explained the majority of the variation observed for pod and seed size. This marker can be used by peanut breeders for marker assisted selection for larger pod and seed size.
Technical Abstract: Pod and seed size are important characteristics for the peanut industry and have been under strong selection pressure since peanut domestication. In order to dissect the genetic control of peanut pod and seed size, a recombinant inbred line mapping population from a cross of Florida-07 by GP-NC WS 16 was used to determine the genomic regions associated with traits including 100 pod weigh, 100 seed weight, pod weight, pod weight of double-seeded pods, seed weight of double-seeded pods, and area of double-seeded pods. Nine QTLs on linkage groups (Lgs) A05, A06, A09, B10, B04, A03, B5 and B8 were associated with pod and seed size. A majority of the QTLs have small effects except the locus on LG A05 (93 Mbp to 102 Mbp) which explains up to 66% phenotypic variations for all of the measured pod and seed traits. A comparison of QTLs previously reported for yield component traits showed a common QTL on LG A05 was detected in two genetic populations whose parentage are distinct from those used in this study. The markers tightly linked to this major QTL were informative in distinguishing large versus small seeded germplasm lines in the minicore collection originating from thirty-one countries, suggesting the preservation of this seed size QTL through peanut improvement and breeding programs worldwide. However, the large seed size allele appeared to co-segregate with a late leaf spot disease susceptibility allele inherited from the Florida-07 parent. Therefor, peanut breeders need to weigh the pros and cons before integrating the large seed size QTL from Florida-07 in their breeding program.