The purpose of this study was to determine the effect of waterlogging duration on the growth characteristics and productivity of forage corn at different growth stages under paddy field conditions. Treatments consisted of waterlogging at two growth stages (V7 or V14) for four waterlogging durations (no waterlogging, 48 hours, 72 hours, and 96 hours, respectively). The V14 growth stage was more vulnerable to waterlogging than the V7 stage. Among the waterlogging durations, the lodging score increased at 48 hours. The stem height of forage corn decreased with the increase in waterlogging duration at the different growth stages (V7 and V14). Increase in waterlogging duration reduced the stem dry matter yield, ear dry matter yield, and total dry matter yield at both growing stages (V7 and V14). The waterlogging treatments at the V14 stage affected ear dry matter yield more than those at the V7 growing stage. Thus, the management of forage corn under paddy field conditions must be strengthened during early (V7) and grain fill stages (V14). When waterlogging occurs, surface and subsurface drainage should be implemented within 48 hours to control (no waterlogging) the groundwater level and, thus, minimize economic losses due to forage corn damage.

ABSTRACT
Ⅰ. INTRODUCTION
Ⅱ. MATERIALS AND METHODS
    1. Experiment site
    2. Plant materials and experimental design
    3. Statistical analysis
Ⅲ. RESULT AND DISCUSSION
    1. Soil moisture content changes
    2. Agronomic characteristics of plants
    3. Productivity of forage corn
Ⅳ. CONCLUSION
Ⅴ. ACKNOWLEDGEMENTS
Ⅵ. REFERENCES

• Jeong Sung Jung(Grassland & Forage Division, National Institute of Animal Science, Rural Development Administration) Corresponding author
• Gi-Jun Choi(Grassland & Forage Division, National Institute of Animal Science, Rural Development Administration)
• Bo-Ram Choi(Grassland & Forage Division, National Institute of Animal Science, Rural Development Administration)