Purdue University research findings indicate that today's hybrid corn varieties more efficiently use nitrogen to create more grain. The researchers recently reviewed 72 years of public sector research data. Tony Vyn, a professor of agronomy, and doctoral student Ignacio Ciampitti looked at nitrogen use studies for corn from two periods – 1940-1990 and 1991-2011. They wanted to see whether increased yields were due to better nitrogen efficiency or whether new plants were simply given additional nitrogen to produce more grain.
“Corn production often faces the criticism from society that yields are only going up because of an increased dependency on nitrogen," Vyn explains. “Although modern hybrids take up more total nitrogen per acre during the growing season than they did before, the amount of grain produced per pound of nitrogen accumulated in corn plants is substantially greater than it was for corn hybrids of earlier decades. So, in that sense, the efficiency of nitrogen utilization has gradually improved.”...
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