Common Garden Experiment Reveals Altered Nutritional Values and DNA Methylation Profiles in Micropropagated Three Elite Ghanaian Sweet Potato Genotypes

Authors

Belinda Akomeah, University of Adelaide, Australia
Marian D. Quain, CSIR-Crops Research Institute, Ghana
Sunita A. Ramesh, University of Adelaide, Australia
Lakshay Anand, University of KentuckyFollow
Carlos M. Rodríguez López, University of KentuckyFollow

Abstract

Micronutrient deficiency is the cause of multiple diseases in developing countries. Staple crop biofortification is an efficient means to combat such deficiencies in the diets of local consumers. Biofortified lines of sweet potato (Ipomoea batata L. Lam) with enhanced beta-carotene content have been developed in Ghana to alleviate Vitamin A Deficiency. These genotypes are propagated using meristem micropropagation to ensure the generation of virus-free propagules. In vitro culture exposes micropropagated plants to conditions that can lead to the accumulation of somaclonal variation with the potential to generate unwanted aberrant phenotypes. However, the effect of micropropagation induced somaclonal variation on the production of key nutrients by field-grown plants has not been previously studied. Here we assessed the extent of in vitro culture induced somaclonal variation, at a phenotypic, compositional and genetic/epigenetic level, by comparing field-maintained and micropropagated lines of three elite Ghanaian sweet potato genotypes grown in a common garden. Although micropropagated plants presented no observable morphological abnormalities compared to field maintained lines, they presented significantly lower levels of iron, total protein, zinc, and glucose. Methylation Sensitive Amplification Polymorphism analysis showed a high level of in vitro culture induced molecular variation in micropropagated plants. Epigenetic, rather than genetic variation, accounts for most of the observed molecular variability. Taken collectively, our results highlight the importance of ensuring the clonal fidelity of the micropropagated biofortified lines in order to reduce potential losses in the nutritional value prior to their commercial release.

Document Type

Article

Publication Date

4-26-2019

Notes/Citation Information

Published in PLOS ONE, v. 14, no. 4, e0208214, p. 1-17.

© 2019 Akomeah et al.

This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Digital Object Identifier (DOI)

https://doi.org/10.1371/journal.pone.020821

Funding Information

This work was supported by the Bill & Melinda Gates Foundation (https://www.gatesfoundation.org) through the International Centre for Genetic Engineering and Biotechnology (https://www.icgeb.org/home.html) to BA, as a capacity building initiative in biotechnology regulation in sub-Saharan Africa, funded this research.

Related Content

All relevant data are within the manuscript and its Supporting Information files.

S1 Fig. Experimental layout. https://doi.org/10.1371/journal.pone.0208214.s001 (DOCX)

S2 Fig. PCoA results of the 12 primer combinations used for MSAP pilot studies. https://doi.org/10.1371/journal.pone.0208214.s002 (DOCX)

S3 Fig. Analysis of molecular somaclonal variation induced by micropropagation of sweet potato. https://doi.org/10.1371/journal.pone.0208214.s003 (DOCX)

S4 Fig. Analysis of epigenetic and genetic variability induced by micropropagation in three sweet potato genotypes. https://doi.org/10.1371/journal.pone.0208214.s004 (DOCX)

S1 Table. Identity, origin, year of release, and preferred ecology of sweet potato genotypes used in the study. https://doi.org/10.1371/journal.pone.0208214.s005 (DOCX)

S2 Table. Scale of reference (1–9) and definition of scores for virus incidence, foliar and root morphological descriptors. https://doi.org/10.1371/journal.pone.0208214.s006 (DOCX)

S3 Table. Oligonucleotides used during Methylation Sensitive Amplified Polymorphisms protocol with their sequences and function. https://doi.org/10.1371/journal.pone.0208214.s007 (DOCX)

S4 Table. Results of selective primer combinations for MSAP pilot study. https://doi.org/10.1371/journal.pone.0208214.s008 (DOCX)

S5 Table. Mean foliage and root quality phenotypic scores for micropropagated (M) and field-maintained (F) populations of three sweet potato genotypes Bohye, Ogyefo, and Otoo. https://doi.org/10.1371/journal.pone.0208214.s009 (DOCX)

Repository Citation

Akomeah, Belinda; Quain, Marian D.; Ramesh, Sunita A.; Anand, Lakshay; and Rodríguez López, Carlos M., "Common Garden Experiment Reveals Altered Nutritional Values and DNA Methylation Profiles in Micropropagated Three Elite Ghanaian Sweet Potato Genotypes" (2019). Horticulture Faculty Publications. 42.
https://uknowledge.uky.edu/horticulture_facpub/42