PT  - JOURNAL ARTICLE
AU  - Marnin D. Wolfe
AU  - Ismail Y. Rabbi
AU  - Chiedozie Egesi
AU  - Martha Hamblin
AU  - Robert Kawuki
AU  - Peter Kulakow
AU  - Roberto Lozano
AU  - Dunia Pino Del Carpio
AU  - Punna Ramu
AU  - Jean-Luc Jannink
TI  - Genome-wide association and prediction reveals the genetic architecture of cassava mosaic disease resistance and prospects for rapid genetic improvement
AID  - 10.1101/031179
DP  - 2015 Jan 01
TA  - bioRxiv
PG  - 031179
4099  - http://biorxiv.org/content/early/2015/11/11/031179.short
4100  - http://biorxiv.org/content/early/2015/11/11/031179.full
AB  - Cassava (Manihot esculenta) is a crucial, under-researched crop feeding millions worldwide, especially in Africa. Cassava mosaic disease (CMD) has plagued production in Africa for over a century. Bi-parental mapping studies suggest primarily a single major gene mediates resistance. To be certain and to potentially identify new loci we conducted the first genome-wide association mapping study in cassava with 6128 African breeding lines. We also assessed the accuracy of genomic selection to improve CMD resistance. We found a single region on chromosome 8 accounts for most resistance but also identified 13 small effect regions. We found evidence that two epistatic loci and/or alternatively multiple resistance alleles exist at major QTL. We identified two peroxidases and one thioredoxin as candidate genes. Genomic prediction of additive and total genetic merit was accurate for CMD and will be effective both for selecting parents and identifying highly resistant clones as varieties.