Irrigation Scheduling for Greenhouse Cucumber Based on Soil Water Potential

The effect of soil matric potential on yield and growth parameters of three varieties of cucumber in greenhouse was carried out during 2012 and 2013 growing seasons in Jiroft area. The treatments were laid out in randomized complete block design with three replications. The treatments were comprised of three soil matric potentials of 45, 60, and 75 centi-bar for initiation of irrigation in the main plot and sub plot consisted of three cucumber varieties (Negin, Hilarious and Dominos). The results showed that water use in treatments 45, 60, and 75 centi-bar tensions was, respectively, 6300, 5100, and 3900 m3 ha-1, which was 18% less than irrigation based on Class A pan evaporation.. Fruit yield, LAI, plant height, and fruit diameter decreased 2.7%, 2%, 2%, 0.73% and 2.3 percent, respectively, but water use efficiency increased 22 percent. On the other hand, yield in Dominos variety compared to Negin and Hilarious increased 6.2% and 6.4 percent, respectively, and water use efficiency increased 13.2% and 13.7 percent, respectively. According to the results, planting Dominos variety and 60 centi-bar soil matric potential for irrigation initiation is recommended to achieve the highest water use efficiency.