ARS | Publication request: Assessment of cotton plant nitrogren status and yield potential using plant height mapping system

Submitted to: Proceedings of the American Society of Agricultural and Biological Engineers International (ASABE)
Publication Type: Proceedings
Publication Acceptance Date: July 29, 2012
Publication Date: August 1, 2012
Citation: Sui, R., Fisher, D.K., Reddy, K.N. 2012. Assessment of cotton plant nitrogren status and yield potential using plant height mapping system. Proceedings of the American Society of Agricultural and Biological Engineers International (ASABE), Paper No.:12-1338431, 6 pp.

Interpretive Summary: Precision agriculture technologies make it possible for farmers to make site-specific adjustment of production inputs for optimal profit. Plant height is one of the key parameters to be considered in crop management. Plant height or plant growth rate can be used as an indicator of plant health status and yield potential. With an understanding of the relationship between plant height and production-related inputs, a plant height map could be used to make site-specific adjustment of inputs such as fertilization and irrigation. The scientists at USDA-ARS, Crop Production Systems Research Unit have conducted an experiment at Stoneville, Mississippi to develop a method to assess plant N status and yield potential in cotton. The experimental plots were laid out in a split plot design with irrigation treatments as main plots and nitrogen treatments as subplots. Cotton plant height was measured using an experimental ultrasonic device coupled with a GPS (global positioning system) receiver. Cotton leaf-blade samples were collected and analyzed for N content. Amount of water applied in irrigated treatment was recorded during the growing season. The plant height showed close relationship with yield. Irrigation had a significant effect on plant height, leaf N content, and yield. Excess application of N would not improve cotton yield.

Technical Abstract: Plant nitrogen status and yield potential are important factors for optimizing field management in cotton production. An experiment was conducted in 2011 at Stoneville, Mississippi to develop a method to assess plant N status and yield potential in cotton. The experimental plots were laid out in a split plot design with two irrigation treatments as main unit and six nitrogen treatments as subunit in a 10-ha cotton field. Cotton plant height was measured in real time in situ using an experimental ultrasonic device coupled with a GPS (global positioning system) receiver. Soil samples were collected and analyzed for soil-N residual and soil texture before planting. Cotton leaf-blade samples were collected and analyzed for N content. Amount of water applied in irrigated treatment was recorded during the growing season. The plant height showed a quadratic relationship with yield, and this relationship was stronger in the non-irrigated plots (R2=0.60) than that in irrigated plots (R2=0.16). Irrigation had a significant effect on plant height, leaf N content, and yield. Excess application of N would not improve cotton yield.