Common methods for editing crops involve using expensive technology to culture cells, essentially growing cells outside the plant in a suitable environment. Once whole plants are recovered from the cells, scientists then screen for the desired traits. Tissue culture technologies are not well developed for many small acreage crops, including common bean. Further, it often takes years for enhanced crops to reach farmers using conventional methods. Yet, new techniques that bypass tissue culturing could reduce the financial risk and time involved in cultivating climate-resilient crops that are less widely studied due to lack of funding or difficulties with editing.
Researchers at UC Davis, led by Dr. Neelima Sinha, are employing a CRISPR DNA-editing technique that edits genes in a seedling’s cells to generate edited shoots while the plant is in soil, eliminating a tissue culture stage. The researchers inject bacteria directly into the seedling. The bacteria carry the gene editing components into the plant cells. After researchers decapitate the seedlings at the injection site, the seedlings generate new shoots to grow at the point of decapitation. Researchers then determine which of the new shoots contain the edited genetic material and continue cultivating them in soil.
“Of the thousands of edible crops species available, about 150 species have been cultivated for consumption. The uncultivated crops, also known as underutilized crops, are a potential treasure trove of nutritional opportunities that could weather climate change disruptions better than some crop varieties we currently grow,” said Dr. Rosichan.
Dr. Sinha and her team have had previous success using this technique in tomatoes. This project is focusing on refining and adapting the process for use in common bean. Common bean was chosen for this study because it is a promising crop with high protein content and good nutritional quality. However, tissue culture and recovery of fertile plants is difficult and limited to specific varieties. The methods developed in this research can provide insights on performing faster and more efficient gene editing in other important food crops that are underutilized because they are difficult to edit or overlooked by the agriculture industry.
“We are excited to embark on this project for improvement of common bean,” said Dr. Sinha. “The nutritional quality of beans is unparalleled and establishing suitable editing methods will open the door to enhancing both quality and the ability of this species to resist disease and grow on a wider range of environments with fewer inputs. This project would not be possible without the money from FFAR and the matching funders.”