Response of Cucumber to Deficit Irrigation

An experiment was conducted in a polyethylene greenhouse at farmers' condition with the objectives of i) determining cucumber response to water stress, ii) quantification of water use in different deficit irrigation programs, iii) defining practical recommendations for water management and iv) assess the crop response factor (ky) and water use of efficiency (WUE) under local conditions. The experiment was designed in three randomized blocks. Each block had four different treatments: (1) Full irrigation, soil water content was allowed to be depleted to 20% of available water content of the plant root zone, (2) Deficit 1, soil water content was allowed to be depleted to 40% of available water content of the plant root zone, (3) Deficit 2, soil water content was allowed to be depleted to 60% of available water content of the plant root zone and (4) Farmer's treatment-control, done according to farmers visual observations. A controller (GP1) was installed in each irrigation treatment in one block and the soil moisture, temperature and salinity were monitored with WET sensor and water-filled-tensiometers were installed at a 20 cm depth and SM200 moisture sensor installed at 40 cm depth. All irrigation and fertilization was undertaken with drip irrigation system. For each treatment, representative plants were grown in containers in order to measure the drained water. The highest yield was obtained from the full irrigation treatment (27.8 kg m(-2)) whereas it was lowest in Deficit 1 (20.3 kg m(-2)). Water consumption of treatments ranked between 387 to 591 mm. WUE values were the smallest in Farmer's treatment and were the greatest in Deficit treatments. Yield response factors varied from 0.66-1.22.