A global overview of cassava genetic diversity

Autoři: Morag E. Ferguson aff001;  Trushar Shah aff001;  Peter Kulakow aff002;  Hernan Ceballos aff003
Působiště autorů: International Institute of Tropical Agriculture, Nairobi, Kenya aff001;  International Institute of Tropical Agriculture, Ibadan, Nigeria aff002;  International Center for Tropical Agriculture, Cali, Colombia aff003
Vyšlo v časopise: PLoS ONE 14(11)
Kategorie: Research Article
doi: 10.1371/journal.pone.0224763


Although numerous studies of diversity have been conducted in cassava, there is no comprehensive assessment of global genetic diversity. Here we draw on previous studies and breeders’ knowledge to select diversity sets from the International Institute of Tropical Agriculture (IITA) and the International Center for Tropical Agriculture (CIAT) genebanks and breeders’ germplasm, as well as elite germplasm and landraces from eastern, southern and central (ESC) Africa to make a global assessment of diversity in cassava, using a SNP based GoldenGate (Illumina Inc.) assay. A synthesis of results from genetic distance and ADMIXTURE analysis essentially revealed four populations (i) South American germplasm characterised by relatively higher genetic diversity with hypothetical ancestral founder genotypes from Brazil, (ii) a smaller group of African introduction germplasm which is more distantly related to all other germplasm, (iii) West Africa germplasm dominated by IITA breeding lines, containing sources of cassava mosaic disease resistance, and IITA genebank accessions from West Africa, both characterised by slightly lower diversity, and (iv) a less cohesive group of African germplasm, termed ‘Other’, with moderate levels of diversity and a majority of germplasm from ESC Africa. This study highlights opportunities for heterosis breeding, purging of duplicates in genebanks and the need for conservation of ESC Africa landraces.

Klíčová slova:

Africa – Heterozygosity – Molecular genetics – Plant breeding – Population genetics – Species diversity – Cassava


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Článek vyšel v časopise


2019 Číslo 11