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POSTERS: Remote Sensing and Sensor Technology

Impact of zebra chip on crop water-use and efficiency of the Irrigation Scheduling Supervisor Control and Data Acquisition (ISSCADA) System
Charles Rush - Texas A&M AgriLife Research. Fekede Workneh- Texas A&M AgriLife Research, Jerry Moorhead- USDA-ARS, Susan O'Shaughnessy- USDA-ARS, Jordan Trees- Texas A&M AgriLife Research

Potatoes in Texas High Plains are irrigated to maximize yield. However, the Ogallala Aquifer has declined significantly, causing an increase in pumping costs. Farmers are trying to improve crop water use efficiency (WUE) and conserve ground water with automated irrigation scheduling systems, such as the ISSCADA system, that are based on remote detection of crop canopy stress. The question was raised how a plant disease, such as zebra chip (ZC), might affect such a system. A study was conducted in which three irrigation treatments were established, 100, 80, and 60% full irrigation, and ZC subplots were established in each main plot. Remote imaging was taken weekly to monitor crop stress and neutron probe readings were taken in all irrigation treatments and ZC subplots to monitor soil water. In all irrigation treatments, soil water content started to accumulate three weeks post-infestation within diseased subplots, suggesting decreased root function of infected plants. Remote sensing at this time did not detect ZC. Soil water continued to accumulate in infested subplots for the remainder of the study. ZC subplots could be remotely detected 50 days after infestation, but not clearly differentiated from drought stress. ZC negatively impacted crop WUE and the efficiency of the ISSCADA system, and soil water measurements in combination with remote sensing of canopy temperature will be required to optimize irrigation scheduling in the presence of plant disease.