Imagine two crops of corn or soybeans each growing season. Plant in March; harvest in July. Plant another crop; harvest in November. What to most farmers would sound like pure foolishness could become a reality within a decade, according to Ray Bressan, professor of horticulture and director of Purdue University's Center for Plant Environmental Stress Physiology, West Lafayette, Ind. He maintains that scientists have learned as much in the past three years as in the previous 100 about how crops and other plants withstand various environmental stresses. The result of this knowledge is that they will soon be able to create new crop varieties that can withstand and even thrive through frost, heat, and drought.
Although doubling crop production will not necessarily cut the amount of farmland in half because of having to feed an ever-increasing world population, the need for cropland could be significantly reduced. An added bonus would be that, by planting two crops per growing season each year, American farmers could take much of the nation's 320,000,000 acres of farmland out of production, thus creating millions of new acres of wildlife habitat.
"A couple of years ago I wouldn't have predicted this? Bressan says. "But within a decade, it will be possible to have crops that can withstand the stresses of early spring and late fall." Drought, heat, frost, salty soil, and nutrient-deficient soil are some of the types of environmental stresses crops must endure. Farmers' worries about these occurrences are as old as praying for rain, and for good reason. They cause massive crop-yield losses every year--more, in fact, than those from insects and weeds.
Bressan points out that scientists have always assumed the ability to thrive through stress was a genetically complex trait, so researchers believed it would be a waste of time to try to create new varieties. Recent discoveries in plant genetics have turned that view upside down, however. "What we're finding is that there are a lot of genes involved, but the good news is that there are less than a couple of dozen--a manageable number of genes--that have significant effect on stress tolerance. …