Potato Irrigation Management Xi Liang Aberdeen Research Extension

Potato Irrigation Management Xi Liang Aberdeen Research & Extension Center, Aberdeen, ID 83210

Crop Water Relations • ETr = transpiration + evaporation • ETc = ETr * Kc http: //ga. water. usgs. gov/edu/watercycleevapotranspiration. html http: //www. usbr. gov/pn/agrimet/chart/abeich. txt

Crop Water Use http: //www 1. agric. gov. ab. ca/$Department/deptdocs. nsf/all/agdex 13571

Irrigation Management - ET J. C. Stark, S. L. Love, B. A. King, J. M. Marshall, W. H. Bohl and T. Salaiz. 2013. Potato Cultivar Response to Seasonal Drought Patterns. Am. J. Potato Res. 90: 207 -216. • Early termination: irrigation applied until the beginning of late bulking • 100/70/50% ET: early bulking - tuber initiation / mid bulking / late bulking • Yield loss from irrigation reduction, and deficit irrigation does not work well in potatoes.

Irrigation Management – ET Potato Root Growth http: //preuniversity. grkraj. org/html/4_PLANT_AND_WATER_RELATIONSHIP. htm http: //nuearthllc. com/id 1. html http: //www. potatogrower. com/Article. aspx? year=2013&month=08&article=2805

Irrigation Management – Soil Moisture B. A. King and J. C. Stark. Potato irrigation management.

Irrigation Management – Soil Moisture • Irrigation was applied only when the soil matric potential reached the targeted values: 15, 25, 35, 45, and 55 k. Pa at 0. 2 m. Optimal yield Y. Kang, F. Wang, H. Liu, and B. Yuan. 2004. Potato evapotranspiration and yield under different drip irrigation regimes. Irrigation Science 23: 133 -143.

Irrigation Management - Canopy Temperature Irrigations were triggered only after canopy temperatures > 28°C for more than 452 min accumulated in a 24 h period. S. A. O'Shaughnessy and S. R. Evett. 2010. Canopy temperature based system effectively schedules and controls center pivot irrigation of cotton. Agricultural Water Management 98: 1310 -1316.

Irrigation Management - Canopy Temperature Treatments: • > 28°C over a 15 min interval • > 30°C over a 15 min interval • > 28°C for more than 4 h on the 3 rd day after irrigation • > 30°C for more than 4 h on the 3 rd day after irrigation • 100% ET weekly • 67% ET weekly Pp. 207 -213 In C. R. Camp, E. J. Sadler, and R. E. Yoder (eds) Evapotranspiration and Irrigation Scheduling. Proc. Internationa Conf. , San Antonio, TX. 1996. ASAE, St. Joseph, MI.

Irrigation Management - Canopy Temperature Thermal imaging Infrared thermometer http: //www. cell. com/trends/plant-science/fulltext/S 1360 -1385(11)00209 -3

Summary • Crop water relations: ET and crop coefficient • Irrigation management: • • • ET Soil moisture threshold Canopy temperature threshold