Why Midwest drought could have been much worse for some corn farmers
Estimates suggest that drought-resistant corn breeds might have diminished potential crop losses by one-quarter this year – a development with major implications for a hotter, more crowded world.
Mr. Sousek now figures he lost half or more of his crop to the drought that scorched the midsection of the country. But he knows this, too: Things could have been much worse.
“You might say I’m pleasantly surprised with the yields,” says Sousek, who was harvesting his corn last week. “Considering what it went though this summer, the extreme heat and lack of rain, it still amazes me that it was able to produce as much as it has.”
Sousek isn’t the only one. Across the Corn Belt, farmers have expressed surprise that their corn endured drought as well as it did – much better, they say, than the varieties they planted just a decade or two ago. In Illinois, for example, one estimate suggests that corn farmers will lose one-quarter less of their crop than they did during the 1988 drought – in large part because of the seeds they planted.
Farmers are benefiting from decades of research in plant breeding combined with a growing interest in crops that can better tolerate drought and other stress. Indeed, research has shown that vulnerability to drought is one of the chief limits to crop production around the world. Meanwhile, gene mapping and other innovations have enabled scientists to develop new varieties with much greater speed and precision than before.
The results are startling, and have implications far beyond the the survival of one year’s harvest in the Midwest. In a world of rising temperatures and population, improvements in drought tolerance are especially urgent.
“We’re heading for 9 billion people in the future,” says Mitch Tuinstra, a researcher at Purdue University in West Lafayette, Ind., who has worked on drought tolerance in corn and sorghum. “If climate change is important, and we have to double the amount of grains we produce, we have to think about how we’re going to adopt to conditions like those we had in the United States this year.”
The improvements are not a cure, say experts. The US Department of Agriculture estimates that farmers this year will harvest 13 percent less corn than last year, despite planting 4 percent more acres.
“Drought can wreak a lot of havoc on crops, even today,” says Emerson Nafziger, a crop specialist at the University of Illinois at Urbana-Champaign.
But the research of the past few decades has yielded plants that are much better at withstanding the conditions that withered crops this year – and that this resilience helped limit farmers’ losses. According to his early projections, Illinois corn farmers will probably lose about 33 percent of their crop this year, compared with 44 percent during the 1988 drought
“If we had the hybrids we had in ’88, we’d be looking at lower yields,” says Mr. Nafziger.
Other farmers agree with Nafziger and Sousek.
“Our yields didn’t dip nearly as much,” says Leon Corzine, who farms in Assumption, Ill., and recalls how 1988 devastated his crop.
Bruce Rohwer, a farmer in Paulina, Iowa, marvelled at how his corn stayed green this year while lawns turned brown – then perked up quickly after August rains. “The plant is absolutely phenomenal, what it can do,” he says.
Several years ago, researchers at Dupont Pioneer, the world’s third-largest seed company, planted modern corn hybrids next to top corn varieties from the past 80 years and exposed the plants to dry conditions. They found that today’s corn is three times more drought tolerant than varieties from the 1930s – and that much of the improvement was in varieties from the past 20 years.
“When you see it in the fields, it’s quite dramatic,“ says Jeff Schussler, senior research manager for Maize Stress at Dupont Pioneer.
Researchers around the world are working to increase the drought tolerance of many crops, including rice, wheat, and sorghum. But corn, the world’s most abundant grain and an immensely profitable crop, has been the focus of research in the United States. Commercial seed companies began marketing drought-tolerant hybrids several years ago, and next year Monsanto, the world’s largest seed company, plans to begin selling genetically modified seed that it says confers even greater drought tolerance.
Farmers are following these developments closely. DuPont Pioneer says farmers planted its drought-resistant AQUAmax seed on 2.5 million acres this year, and it expects them to plant even more next year.
“There’s a huge interest in anything that’s going to get you a crop when you have a situation like this,” says Greg Kruger, an agronomist at the University of Nebraska, Lincoln.
Scientists say modern crops are better at tolerating drought because of improvements like more efficient roots and greater resistance to insects. Farmers also deserve credit for adopting practices like “conservation tillage,” which preserve soil moisture and make it easier for plants to send their roots deep.
Mr. Tuinstra of Purdue says his own research, which involves cross-breeding plants from a wide range of the world’s 20,000 corn varieties, has shown promise. But making plants more drought tolerant is far from easy. The biggest challenge, scientists say, is to produce crops versatile enough to do well when the rains fail, but also when they don’t.
Moreover, “it’s going to be hard” to match past gains, says Mr. Schussler of Dupont Pioneer. “We have made major improvements already, optimizing parts of the plant.”
For his part, Mr. Corzine of Assumption worries that farmers will expect too much. “There’s no miracle cure for extreme weather,” he says. Still, he’s considering planting “a few bags” of the newest drought-tolerant varieties next year. “I might try a little bit of that and see how it does.”