Monday, 1 June 2020
New trials run by Innovative Farmers Field lab and funded by AHDB will research the possibility of using brackish water for potato irrigation.
Why are these trials required?
Irrigation plays a vital role in potato quality. Growers in areas such as Holbeach Marsh, one of the driest regions in the UK, are facing considerable economic yield losses due to common scab.
Under future climate projections we anticipate more unpredictability in rainfall events, increased saline intrusion of groundwater reserves and therefore a more vulnerable freshwater supply, which could impact on potato yields in the area. As such, local growers are keen to explore novel ways of irrigation management to reduce water usage without affecting yields or soil health.
Grower members of Nene Potato Ltd planned a trial on use of slightly saline water with those able to offer technical support. The two aspects being investigated are effect of salinity and benefit of application by drip when using brackish water.
Trials set up
The trials will be conducted on five fields, on which the following treatments will be studied:
- Plot A: Drip irrigation with (high) brackish water (2000 ppm)
- Plot B: Drip irrigation with mains water (400 ppm)
- Plot C: Drip irrigation with (low) brackish water (950 ppm)
- Plot D: No Irrigation
- Plot E: Overhead Irrigation with (low) brackish water (950 ppm)
The soil will be tested for the effects of these treatments on its physical, chemical and biological quality. Crop growth and yield will be recorded.
Why drip irrigation?
Drip irrigation can be a much more efficient use of water than overhead delivery on silt soils. It could also avoid the problems of delivery into the ridge in hydrophobic soils and leaf scorch from a brackish application. In this trial, brackish water treatments will be applied via drip irrigation, and compare with an adjacent overhead delivery system.
When will we have the final results?
The final results are expected at the end of this year.