Fiziol. rast. genet. 2021, vol. 53, no. 1, 29-54, doi:

Induced mutagenesis in wheat: from ionizing radiation to site-specific gene editing

Kishchenko O., Stepanenko A., Borisjuk M.

  1. Jiangsu Collaborative Innovation Centre of Regional Modern Agriculture & Environmental Protection, School of Life Science, Huaiyin Normal University, Huai’an, China
  2. Institute of Cell Biology and Genetic Engineering, National Academy of Sciences of Ukraine 148 Akademika Zabolotnoho St., Kyiv, 03143, Ukraine

Wheat (Triticum aestivum L.) occupies the largest cultivated area among crops, supplying a substantial part of energy, nutrients, fiber and protein to human. Whereas the wheat yield has been significant enhanced during the Green Revolution, the food needs also increases with the growth of human population. The breeding of highly productive cultivars with improved agronomic and nutrient characteristics remains an important challenge. Since the beginning of 20th century, induced mutagenesis using ionizing radiation and various chemicals has been practiced to increase the diversity of plant material in breeding. The method represents an effective tool for inducing a wide range of genetic changes. However, the vast majority of the generated random mutations, are rather deleterious and have to be cleaned up via cumbersome and time-consuming back-crossing procedures. Instead, site-specific endonucleases offer an opportunity of accurate and efficient target-specific modifications in the chosen loci selected by a researcher. The review provides a historic perspective on the induced mutagenesis technologies and the recent progress in genome editing based on customizable endonucleases. The main focus is on the advances of CRISPR/Cas technology, which emerged as the most widely used mean for crop genomes editing, including wheat with its complex hexaploid genome. The areas of application of the CRISPR/Cas systems for wheat improvement are described in detail. Particular attention is paid to the development of new approaches, based on genome editing systems for speeding up the production of wheat hybrids, improving wheat productivity and nutritional values. The legal regulations applied to the production and applications of the organisms obtained by targeted mutagenesis are also discussed.

Keywords: Triticum aestivum L., wheat, induced mutagenesis, genome editing, CRISPR/Cas9

Fiziol. rast. genet.
2021, vol. 53, no. 1, 29-54

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