COMPARISON OF TWO IRRIGATION MANAGEMENT SYSTEMS IN STRAWBERRY
In Switzerland, the major part of the 420 ha of strawberry crops are cultivated on plastic-covered raised beds equipped with drip irrigation. The irrigation management is based on monitoring the soil moisture. Such a monitoring, if based on the visual reading of tensiometers combined with a manually operated irrigation system, is time consuming. In Switzerland, salaries are high and are a major production factor. The use of fully automatic irrigation management systems might help reduce production costs, and eventually reduce the amount of water used for irrigation. A trial comparing two irrigation management systems was conducted during two years at the Agroscope ACW at Conthey located in the southern part of Switzerland. The cultivar Clery was grown under two tunnels. The irrigation of each tunnel was managed with a different irrigation system. The first used tensiometers to monitor soil moisture at 20 cm depth. Irrigation cycles of 8 or 12 L/m2 were started manually at a 20 cbar threshold. This corresponded to 1-2 irrigation cycles per week. The second irrigation management system was based on Watermark sensors at 20 cm depth and was piloted by WEM (Watermark Electronic Module). Up to three irrigation cycles of 1.3 L/m2 could be delivered per day. An irrigation cycle was started when the 20 cbar threshold was reached at one of three times per day: 7:30, 11:00 and 15:00. During the irrigation period (March 28 to June 10), the average daily amount of water consumption was 2.5 L/m2 for the manually managed and 1.3 L/m2 for the WEM-piloted irrigation management system. There were no significant differences between yield and fruit size between the two irrigation management systems. In the manually managed system, the higher water consumption can be explained by over-irrigation during the spring period. The WEM-piloted systems avoided such a waste of irrigation water. Even though irrigation water is cheap in Switzerland (1.8 US$/m3), the WEM allowed savings of 1,580 US$/ha. The reduction in labor between the WEM system and the manually operated system was estimated to be 20 h/ha, which resulted in savings of 680 US$ in labor costs. The amount of money saved (2,260 US$) was greater than the costs for a WEM-set (2,200 US$). Given an expected duration of the WEM-system of 3-5 years, a switch from a manually managed to an automatic managed irrigation system is fully justified.
Ançay, A., Vincent, M. and Baroffio, C.A. (2014). COMPARISON OF TWO IRRIGATION MANAGEMENT SYSTEMS IN STRAWBERRY. Acta Hortic. 1049, 529-533
strawberry, irrigation, soil moisture measurement, water saving