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Plant function and evolutionary biology
REVIEW

Epigenetic changes and their relationship to somaclonal variation: a need to monitor the micropropagation of plantation crops

Parisa Azizi https://orcid.org/0000-0001-5464-6761 A C , Mohamed M. Hanafi https://orcid.org/0000-0003-1898-6819 A B C F , Mahbod Sahebi C , Jennifer A. Harikrishna D , Sima Taheri D , Ali Yassoralipour E and Abbas Nasehi A
+ Author Affiliations
- Author Affiliations

A Laboratory of Plantation Science and Technology, Institute of Plantation Studies, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia.

B Department of Land Management, Faculty of Agriculture, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia.

C Laboratory of Climate-Smart Food Crop Production, Institute of Tropical Agriculture and Food Security, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia.

D Centre of Research in Biotechnology for Agriculture (CEBAR), University of Malaya, 50603, Kuala Lumpur, Malaysia.

E Department of Agricultural and Food Science, Faculty of Science (Kampar Campus), Universiti Tunku Abdul Rahman (UTAR), Jalan Universiti, Bandar Barat, 31900 Kampar, Perak, Malaysia.

F Corresponding author. Email: mmhanafi@upm.edu.my

Functional Plant Biology 47(6) 508-523 https://doi.org/10.1071/FP19077
Submitted: 22 March 2019  Accepted: 23 February 2020   Published: 30 April 2020

Abstract

Chromatin modulation plays important roles in gene expression regulation and genome activities. In plants, epigenetic changes, including variations in histone modification and DNA methylation, are linked to alterations in gene expression. Despite the significance and potential of in vitro cell and tissue culture systems in fundamental research and marketable applications, these systems threaten the genetic and epigenetic networks of intact plant organs and tissues. Cell and tissue culture applications can lead to DNA variations, methylation alterations, transposon activation, and finally, somaclonal variations. In this review, we discuss the status of the current understanding of epigenomic changes that occur under in vitro conditions in plantation crops, including coconut, oil palm, rubber, cotton, coffee and tea. It is hoped that comprehensive knowledge of the molecular basis of these epigenomic variations will help researchers develop strategies to enhance the totipotent and embryogenic capabilities of tissue culture systems for plantation crops.

Additional keywords: chromatin modulation, epigenetic changes, histone modification, DNA methylation, tissue culture system.


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