Plant water stress index in corn
OPE3 is an interdisciplinary research project started in 1998 addressing various major environmental and economic issues facing U.S. agriculture today. Located in Maryland, USA the OPE3 sites' primary foci are the
environmental aspects of precision farming. Through the use of the Sentek Sensor EnviroSCAN technology, researchers can now identify the spatial location and timing of surface and subsurface chemical losses as they have an accurate knowledge of soil water dynamics.
Sentek's Irrigation and Hydrology Manager, Peter Buss, installed 48 EnviroSCAN soil moisture probes with a total of 256 sensors throughout the OPE3 site.
These millions of data points provide the backbone for moisture monitoring research.
Economic impact of too little water
One of the many outcomes from the project was the quantification of the impact of stress days on corn yield. Three seasons of data provided a good spread of yield and stress data. The stress days can be easily counted from the water dynamics at each site as identified by the slowdown in photosynthetic rate (onset of stress) shown on the IrriMAX graph (left).
The 15 stress days recorded on the graph, resulted in a 50% yield reduction! The graph shows that even 2 days of stress results in 10% yield loss which, when combined with yield data, quantifies to up to 40% of profits.
Economic impact of too much water
In other research, the University of Nebraska- Lincoln highlighted the negative aspects of over watering. These include reduced root oxygen, increased toxicity build-up, increased negative microbial growth and root disease and less roots due to lower soil temperature. Losses of between 8-15 bushels/ average acre ($43 -$81 in profits) were measured due to over-irrigation by 25%.
This information is invaluable in informing corn growers of irrigation strategies to optimize yield and profit.