Abstract
Nitrous oxide (N20) is a greenhouse gas that is three hundred times more
potent than carbon dioxide. The majority of N20 emissions worldwide are
the result of excess soil nitrogen being metabolized by microbes. It has
been hypothesized that crops with better nitrogen uptake efficiency and
more roots will reduce excess soil nitrogen therefore reducing N20
emissions. To test this hypothesis, a pilot study was performed in 2021
in collaboration with Iowa State University in which root growth
dynamics were captured using RootTracker ™ technology in four commercial
maize hybrids. This preliminary study showed a correlation between
increased root growth and reduced N20 emissions. Further, we find
genetic differences in root growth that is consistent across reps,
suggesting that i) cultivar choice impacts N2O emissions and ii) that it
is possible to breed for root system architecture to limit N2O
emissions. It was also observed that the hybrid with the fastest rate of
root growth (lowest N20 emissions) did not reach the greatest soil
depth, suggesting early root establishment could be pivotal to more
efficient nitrogen uptake. These preliminary results suggest there are
differences in root growth by variety that could be exploited to reduce
agricultural N20 emissions at scale.