Recent advances in crop transformation technologies

Agriculture is experiencing a technological inflection point in its history, while also facing unprecedented challenges posed by human population growth and global climate changes. Key advancements in precise genome editing and new methods for rapid generation of bioengineered crops promise to both revolutionize the speed and breadth of breeding programmes and increase our ability to feed and sustain human population growth. Although genome editing enables targeted and specific modifications of DNA sequences, several existing barriers prevent the widespread adoption of editing technologies for basic and applied research in established and emerging crop species. Inefficient methods for the transformation and regeneration of recalcitrant species and the genotype dependency of the transformation process remain major hurdles. These limitations are frequent in monocotyledonous crops, which alone provide most of the calories consumed by human populations. Somatic embryogenesis and de novo induction of meristems — pluripotent groups of stem cells responsible for plant developmental plasticity — are essential strategies to quickly generate transformed plants. Here we review recent discoveries that are rapidly advancing nuclear transformation technologies and promise to overcome the obstacles that have so far impeded the widespread adoption of genome editing in crop species.

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Acknowledgements

Research in the Gallavotti lab is supported by grants from the National Science Foundation (IOS nos 1546873, 1916804 and 2026561). Research in the Dubcovsky lab is supported by grants no. 2022-68013-36439 and no. 2022-67013-36209 from the USDA National Institute of Food and Agriculture and by the Howard Hughes Medical Institute.

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Authors and Affiliations

  1. Waksman Institute of Microbiology, Rutgers University, Piscataway, NJ, USA Zongliang Chen & Andrea Gallavotti
  2. Department of Plant Sciences, University of California Davis, Davis, CA, USA Juan M. Debernardi & Jorge Dubcovsky
  3. Howard Hughes Medical Institute, Chevy Chase, MD, USA Juan M. Debernardi & Jorge Dubcovsky
  4. Department of Plant Biology, Rutgers University, New Brunswick, NJ, USA Andrea Gallavotti
  1. Zongliang Chen