Modern hybrids absorb more than half of their final N content after flowering. In fact, they absorb 27% more total N from the soil after flowering than hybrids grown between 1950 and 1990, says a newly released Purdue study.
Today’s hybrids absorb more grain-N during grain fill, as opposed to N being remobilized from plant leaves and stems. The higher amount and duration of N uptake contributed to better grain yields, even as actual grain N concentrations decline; hybrids are much more efficient. But as corn plants increase N use, they increase their uptake of other nutrients....
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