Conventional plant breeding is beating GM in the race to produce crops than can tolerate climate stresses, concludes the author of an article published in the science journal Nature.
The article highlights work being undertaken by the Drought Tolerant Maize (DTM) project, which has been using traditional plant breeding methods to develop new maize varieties that can tolerate drought (which can reduce yields by 25%). It has already developed 153 new varieties that, in field trials, have matched or exceeded commercial seeds under good rainfall conditions, and yield up to 30% more under drought conditions.
The project’s success has been helped by having access to a large seed bank managed by the International Maize and Wheat Improvement Center (CIMMTY) in Mexico City. DTM researchers have been able to search the collection for varieties that thrive in water-scarce regions, cross-breed these and then mate the most drought-resistant of their offspring. CIMMTY is also developing GM varieties of drought-resistant maize in collaboration with Monsanto. But the Nature article notes that a transgenic variety is “unlikely to be ready for African farmers before 2016″.
The Nature article’s author, Natasha Gilbert, points out that drought tolerance is a complex trait involving multiple genes. GM techniques, which target one gene at a time, have simply not be as quick to manipulate it. Gilbert suggests that conventional breeding may prove to be quicker to achieve solutions in other situations – such as nitrogen-poor soils – that are also genetically complex.
Commenting on, and developing, the issues raised in the Nature article, Dr Doug Gurian-Sherman (director of sustainable agriculture at the US Center for Food Safety), commented: If done right, conventional breeding and agroeocology can both improve agriculture in many ways. But achieving this potential means getting our priorities straight and seeing beyond silver-bullet solutions. The latest Nature article demonstrates a step in the right direction in recognizing one piece of this puzzle.”
