Deployment of new biotechnologies in plant breeding

Pod Shattering: A Homologous Series of Variation Underlying Domestication and an Avenue for Crop Improvement

“…Nevertheless, the products of these new plant breeding techniques can be i) crops with new genetic material, ii) crops without new genetic material, but with modified DNA, or iii) crops without new or modified genetic material [141]. Depending on whether the end products will be classified under genetically modified crops or not, these methods may need extensive regulations and may be met with resistance, which will increase the time cost and alter the market dynamics [140]. Overall, breeding programs would benefit from the development of high-efficiency methods that can be tailored to different genes and crops of interest.…”

“…A general advantage of all these new techniques is that they all save time by speeding up the breeding process due to increased efficiency and specificity. Another advantage of these target-specific methods is that they only introduce the desired gene(s) into the crop, thereby minimizing the contamination of the crop with unwanted genetic material via linkage drag [140]. However, gene editing approaches are still in their infancy, and further improvements are necessary.…”

“…With the introduction of marker-assisted breeding, traditional methods gained efficiency, but their use is still limited in crops with complex genomes, polyploidy, self-incompatibility, and long generation time [141]. Chemical and radiation-induced mutations can also increase genetic variation, but screening for beneficial mutations while selecting against undesired ones can be time-consuming and expensive [140]. Therefore, even though these methods remain an important part of crop improvement, new techniques are necessary to produce and increase genetic variation in crop species and to increase the efficiency in plant breeding programs.…”

“…Early plant breeding efforts were limited to utilizing the advantageous traits via selective breeding, which is a slow process and not a viable option in a rapidly changing environment. The crop improvement process is accelerated via micropropagation, which allows rapid expansion of stock plants, and embryo rescue, which allows crossing of incompatible plants [140]. With the introduction of marker-assisted breeding, traditional methods gained efficiency, but their use is still limited in crops with complex genomes, polyploidy, self-incompatibility, and long generation time [141].…”

“…These include agroinfiltration [142], which uses bacterial transformation to induce gene expression, oligonucleotide-directed mutagenesis [143], and zinc-finger nuclease technology [144], both of which allow site-specific gene manipulation; and cisgenesis and intragenesis [145], which involve gene transfer from the same or a cross-compatible species, resulting in plants that can be practically generated using traditional breeding techniques, but in much shorter periods of time [140]. The CRISPR-Cas9 system, and related CRISPR systems, are a set of recently developed tools for site-specific genome editing that introduces modifications to the genome at precisely targeted regions, thereby minimizing off-site effects [146].…”