A team of biologists and agronomists has identified genomic signatures in plants indicating they are resilient to stresses such as drought or toxic soils. The multi-year study, expected to help developing-world farmers, was done with sorghum, one of the world’s most common crops. It appears in the journal Science Advances.
“It is abundantly clear that climate change will have major impacts on crop yields around the world,” said lead author Jesse Lasky, who conducted most of the work while a fellow at Columbia University’s Earth Institute. “The most consequential impacts may occur in the developing world, where the risks are not merely rising food costs, but crop failure and potentially famine. This project is intended to help equip breeders in the developing world with information that will help them develop environmentally appropriate and resilient crops that mitigate the risks posed by climate change.”
The researchers chose sorghum because of its importance as a staple crop for over half a billion people in some of the harshest agricultural regions of Africa and Asia. Also, its genome had been previously sequenced and assembled.
Lasky (now about to take up a position at Pennsylvania State University) worked with Geoff Morris at Kansas State University, as well as researchers at Clemson University, Cornell University, the University of Texas at Austin, and the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT).
Collaborators at Cornell and ICRISAT sampled about 2,000 sorghum varieties from extensive crop gene banks and then took “snapshots” of genetic variations across the genome. Because each sorghum variety was from a particular known location in an African or Asian village, Lasky and Morris were able to tie the genetic differences of each variety to its home environment. In doing so, researchers found each sorghum variety’s genomic signature indicated its environmental adaptations. This signature predicted how different plant varieties would respond to specific stresses, including drought. In order to validate drought resistance, ICRISAT and the University of Texas applied a drought stress test to hundreds of different sorghum varieties. These experiments showed that the genomic signatures could identify which varieties are most resilient.
The researchers have cataloged the findings in a freely available database aimed at helping sorghum producers in developing countries make better predictions about which varieties will thrive in specific environments, and how varieities will respond to long-term climate change.
The study is part of a project funded by the U.S. National Science Foundation and the Bill and Melinda Gates Foundation that is developing new technologies for crop improvement.
