A Killer Lurks Among Us

October 31, 2011
Doug Gurian-Sherman
Former contributor

From the smell of freshly baked bread, to spaghetti, couscous, chapattis and naan, wheat, the staff of life, is an iconic food. It is also one of the world’s most widely grown crops, supplying about 31 percent of human food calories.

Wheat is a versatile food, high in protein and other nutrients. The unique properties of wheat proteins and selection of desirable traits over the millennia have resulted in flour that gives western bread dough its ability to produce loaves. Breeding has also produced pastry wheat that gives baked goods their flaky quality, and pasta wheat that imparts a chewy texture.

Wheat is also plagued, as are all crops, by a variety of diseases, some of which can wither entire regions. One of the most devastating is called stem rust, which produces spores that can spread hundreds of miles or more in a summer. Where the right conditions exist, losses can be 50 to 70 percent regionally, and as high as 100 percent locally. Stem rust is joined by stripe rust, leaf rust, and other pathogens, in the pantheon of wheat diseases.

Wheat stem rust, USDA photo by Yue Jin

Enter the villain

Although there has been justifiable concern about the potential of drought  to drastically reduce the harvest of wheat and other crops, resulting in increased food prices that have swelled the ranks of the malnourished, most have probably never heard of wheat rust.

In part, that is because stem rust and its cousins have been successfully controlled for over 50 years through public sector conventional breeding programs that provided wheat with resistance to these diseases.

Recently, though, a new and virulent strain of stem rust, called Ug99, emerged in Uganda. As with the ability of bacteria to evolve resistance to antibiotics, plant pathogens can, and will, evolve to overcome the ability of plants to fight them off. If not stopped, this new strain (or race as plant pathologists call it) could cause tremendous losses of wheat world-wide.

Public sector science steps up

That is why the low-key announcement from the U.S. Department of Agriculture that it has found resistance to the new stem rust in its collection of wheat varieties from around the world, called landraces, is such good news. This discovery, along with those of USDA’s international collaborators, should allow conventional crop breeders to deploy the new resistance into commercial wheat varieties, heading off possible disaster.

Nothing better illustrates the value of public sector research. Do we really want to gamble our food supply on whether the private seed sector would step in and do what is needed?

Although not as dramatic as the situation with stem rust, the collective results of agricultural crop breeding research are invaluable, with resistance to pathogens of virtually all crops, improved quality, stress resistance, improved yield, and many other properties resulting from these efforts. Recent work on sustainable and organic agriculture is also valuable, especially for reducing agriculture’s substantial environmental impacts and making crops more resilient in the face of climate change.

Reaping what we sow?

This is why recent public research funding cuts, and possible future cuts in the name of debt reduction, are so disturbing.

Unfortunately, research budgets are mostly out-of-sight-out–of-mind, lost in frantic discussions about debt and legitimate immediate concerns about jobs.

USDA and journalists need to do a better job of reminding the public how important this research can be. They have a responsibility to communicate this work more broadly, so that the public and its representatives can make informed decisions about supporting it.

But if political expediency prevails, and if we don’t better prioritize and maintain crucial public research spending, we will all come to regret the results.