Scientists have agreed on a $US109 million ($105 million) plan to strengthen the world's biggest seed banks of crops such as rice and wheat to help protect and develop new varieties resistant to climate change and other threats.

The Global Crop Diversity Trust and the CGIAR Consortium of agricultural researchers said on Thursday that a five-year plan would help secure storage of more than 700,000 samples of crops at 11 existing gene banks from the Philippines to Belgium.

Reaping what we sow: climate change set to impact on crops. Credit:Tamara Voninski

"This will drive the creation of a real global system" to help safeguard food crops, Cary Fowler, outgoing head of the Bonn-based Trust, told Reuters in a telephone interview.

The funds will allow the collections to expand, put more information about genetic makeup of seeds on the Internet, and enable duplication of more seeds, partly to ensure that conflicts such as those occurring now in Syria or Mali do not wreck collections.