Nuclear Techniques Help Develop New Sorghum Lines Resistant to the Parasitic Weed Striga

Striga attacks crops from under the ground — its seeds remain viable in soil for over 20 years — sucking nutrients and water from their roots, killing crops in hordes. The two most destructive Striga strains are Striga hermonthica and Striga asiatica, Ghanim said.

To combat Striga, new varieties of sorghum have been developed using irradiation, in a technique known as plant mutation breeding (see What is Plant Mutation Breeding?). “Thanks to Glass-house and field trials, we succeeded in the selection of improved lines, and we expect that new resistant varieties developed from these lines will be released to farmers within the next two years, in some of the participating countries,” Ghanim said.

In plant breeding programmes, the primary challenge is to identify new and improved lines, with desired traits, before they can be developed into varieties that can be cultivated by farmers. The ongoing research and development using irradiation has identified such lines with proven resistance to Striga, and these are being developed into varieties that can be disseminated to farmers in the near term.

“I am so excited to see the power of nuclear technology applications for mutation breeding;  I hope the varieties developed from the improved sorghum lines selected in this project will finally restore production of cereals in the heavily Striga infested areas in Africa,” said Phillipe Nikiema, a researcher at Burkina Faso’s Institute for the Environment and Agricultural Research and a participant of an IAEA Striga coordinated research project.

The results of this project focus specifically on understanding and developing solutions for resistance to Striga in cereal crops, involving experts from twelve countries.

“The affected African countries, including my own, Burkina Faso, will benefit from new improved sorghum lines and varieties developed through this project.  Results of the project will also help to understand the physiological and molecular bases of host-parasite interaction to enable the development of further solutions to restore cereals production and boost food security in Africa,” he added. “Striga threatens food security in rural areas where it has been expanding and taking over millions of hectares, including those owned by of poor farmers.”

Experts are now analysing the induced resistance in different sorghum varieties to enable combining more than one defense mechanism and produce even more resistant sorghum varieties to restore production and ensure food security and the livelihoods of farmers.