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Traditional plant breeding methods alone are insufficient to guarantee food security for a growing global population under a changing climate, necessitating more advanced approaches to develop productive and resilient crop varieties. The development of genome editing tools, particularly CRISPR/CAS, are significantly speeding up crop improvement by enabling targeted breeding in most crop species. However, for many crop species, the need for tissue culture remains a major bottle neck, slowing the progress of crop improvement. In this review, we are presenting and discussing approaches for delivering genome editing tools into a wide variety of crop plants, including perennials, and ideally without integration of transgenes. We suggest that efficient non-tissue culture delivery systems for high-performance genome editing are needed to fully reach the genome engineering potential in crop plants.
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Using targeted genome methylation for crop improvement
Abstract Genome editing allows scientists to specifically change the DNA sequence of an organism. This powerful technology now fuels basic biology discovery and tangible crop improvement efforts. There is a less well understood layer of information encoded in genomes, known collectively as ‘epigenetics’, that impacts gene expression, without changing the DNA sequence. Epigenetic processes allow organisms to rapidly respond to environmental fluctuation. Like genome editing, recent advances have demonstrated that it is possible to edit the epigenome of a plant and cause heritable phenotypic changes. In this review, we aim to specifically consider the unique advantages that targeted epigenome editing might provide over existing biotechnology tools. This review is aimed at a broad audience. We begin with a high-level overview of the tools currently available for crop improvement. Next, we present a more detailed overview of the key discoveries that have been made in recent years, primarily using the model system Arabidopsis, new efforts to extend targeted methylation to crop plants, the current status of the technology, and the challenges that remain to realize the full potential of targeted epigenome editing. We end with a forward-looking commentary on how epi-alleles might interface with breeding programs across a variety of crops.
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- Award ID(s):
- 2331437
- PAR ID:
- 10609679
- Publisher / Repository:
- Oxford University Press
- Date Published:
- Journal Name:
- Journal of Experimental Botany
- Volume:
- 76
- Issue:
- 9
- ISSN:
- 0022-0957
- Format(s):
- Medium: X Size: p. 2394-2404
- Size(s):
- p. 2394-2404
- Sponsoring Org:
- National Science Foundation
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