DArTSeq SNP-based genetic diversity and population structure studies among taro [(Colocasia esculenta (L.) Schott] accessions sourced from Nigeria and Vanuatu

PLoS One. 2022 Nov 10;17(11):e0269302. doi: 10.1371/journal.pone.0269302. eCollection 2022.

Abstract

Taro is a valuable staple food crop among resource-poor rural people in countries such as Nigeria and Ghana, among others. Characterization of genetic diversity is a prerequisite for proper management of breeding programs and conservation of genetic resources. Two hundred seventy one taro accessions obtained from Nigeria and Vanuatu were genotyped using DArTseq-based SNP markers with the objectives of investigating the genetic diversity and population structure. In the analysis, 10,391 SNP markers were filtered from the sequence and used. The analysis revealed higher transition than transversion types of SNPs in the ratio of 1.43:1. The polymorphism ranged from 0.26 to 0.29 for the markers, indicating moderate genetic diversity. A model-based Bayesian clustering analysis of taro accessions yielded five subgroups and revealed the admixture situation in 19.19% of all accessions in the study. Vanuatu taro accessions exhibited more genetic diversity than Nigerian taro accessions. The population diversity estimate (PhiPt) was relatively higher (0.52) for accessions originating from Vanuatu than for Nigerian accessions. Analysis of molecular variance (AMOVA) revealed that most variation existed among individuals within a population at 52%. Nei's genetic distance showed that relatedness is based on geographical proximity. Collection of taro genetic resources should give more emphasis to within regions to utilize diversity in taro breeding program. This study also demonstrated the efficiency of DArTseq-based SNP genotyping for large-scale genome analysis in taro. The genotypic markers provided in this study are useful for association mapping studies.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bayes Theorem
  • Colocasia* / genetics
  • Genetic Variation
  • Humans
  • Nigeria
  • Plant Breeding
  • Polymorphism, Single Nucleotide
  • Vanuatu

Grants and funding

The first author (PhD student at the time of doing research) was financially supported by European Union for his stipend, insurance and limited amount of research fund (Project no. 2016–2988). Integrated Genotyping Service and Support (IGSS) of the Biosciences Eastern and Central Africa (BecA-ILRI) Hub, Nairobi subsidized the genotyping services. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.