Drip Irrigation And Fertigation Of Potato Under Light- Textured Soils Of Cappadocia Region

Abstract

Soils in the Cappadocia region of Turkey are mainly light-textured (sandy, loamysand, or siltloam) and the prevailing irrigation method used by the farmers is sprinkler. Due to the very high N fertilizer and water usage (nearly 100 kg N/da and 1400-1700 mm of water, respectively) by the farmer in the region for the potato production, some researchers (Karaca and Demir, 1994; Halitligil et al., 2002) conducted field experiments at different locations in the region. Karaca and Demir, 1994 reported that 550 kg N/ha is the economical rate for potato under these light-textured soils. Halitligil et al., 2002 conducted field experiments with potato using ¹⁵N labelled fertilizer in order to find out the N balance under sprinkler irrigation in the region rate. Their results showed that nearly half of the applied fertilizer N (45.6 %) at 40 kg N/da rate and more than half of the applied fertilizer N (60.8 %) at 100 kg N/da rate was in 0-200 cm depth in the soil after harvest. In the region, the water for irrigation, animal and as well as human use is directly pumped from the ground water resources due to lack of other resources. As a result of their their findings, the researchers suggested that some agricultural measures to prevent or decrease the nitrate contamination of ground waters (as changing the prevailing sprinkler irrigation system to the drip irrigation-fertigation system) must be taken after the completion of the necessary investigations of the new irrigation + fertigation system in the region.