zmm28 transgenic maize increases both N uptake- and N utilization-efficiencies

Area of Science:

• Agricultural biotechnology
• Plant genetics
• Crop science

Background:

• Maize (Zea mays L.) hybrids require efficient nitrogen (N) utilization for optimal yield.
• Biotechnology offers tools to enhance N use efficiency in crops.
• Previous studies indicated positive effects of zmm28 transcription factor (Event DP202216) on maize yield.

Purpose of the Study:

• To investigate the impact of the DP202216 trait on maize N uptake and utilization.
• To compare N metabolism in DP202216 transgenic hybrids versus wild-type (WT) controls.

Main Methods:

• Utilized isotope 15N labeling to track nitrogen assimilation.
• Compared N uptake, N harvest index, and N remobilization between transgenic and WT maize.
• Evaluated N uptake efficiency and N utilization efficiency.

Main Results:

• DP202216 hybrids exhibited enhanced N uptake during late vegetative stages, with N storage in lower canopy leaves.
• Transgenic hybrids demonstrated improved N uptake efficiency (N uptake to applied N ratio) compared to WT.
• Greater N harvest index and reproductive N remobilization resulted in superior N utilization efficiency (yield to N uptake ratio) in DP202216 plants.

Conclusions:

• The DP202216 trait significantly improves nitrogen uptake and utilization efficiencies in maize.
• This genetic modification offers a promising strategy for enhancing crop productivity and sustainability.
• Event DP202216 presents new opportunities for developing nitrogen-efficient maize varieties.