M.K. Reddy, Group Leader of the Crop Improvement lab has received a grant from the Department of Biotechnology, Government of India to address rice blast disease, which causes serious damage to rice production worldwide.
Rice blast is one of the most destructive diseases caused by the fungus, M. oryzae. Currently, the rice blast disease is managed through incorporating various dominant resistance ‘R’ genes from the rice germplasm. The R gene, which earlier confered high levels of resistance, was found to lose resistance to the newly evolved M. oryzae pathotype. In general, different R-gene(s) are often required to confer resistance to different isolates of M. oryzae.
The availability of different R genes is the bottleneck, and pyramiding of these R genes from a wide spectrum of genetic backgrounds may lead to linkage drag in conventional, time-consuming, breeding methods.
The Department of Biotechnology (DBT) recently awarded a grant to ICGEB New Delhi to address this issue.
Under this new project, ICGEB aims to select a few rice genes whose expression is essential for the establishment of rice blast and whose knockout rice lines would be blast resistance. While these genes were not available in the rice germplasm, M.K. Reddy, heading the Crop Improvement lab at ICGEB New Delhi, proposed to generate these genes directly in the elite rice lines using target genome editing technology.
It is anticipated that the resulting, edited rice lines with loss of function of these selected genes will gain the durable blast resistance trait without any further requirement for actual rice mutants, and eliminating time-consuming plant breeding processes.
While the genome editing tools will be initially introduced into the plant through a transgenic approach, it is often unlinked to the site of DNA modification and can be removed by segregation in subsequent generations. Thus the new lines generated through this method will be non-transgenic and preventive to this most destructive rice blast disease.