Water saving and water productivity under buried clay pot and drip irrigation systems for cabbage in Rwanda

Abstract

This research evaluated the effects of Clay Pot Irrigation System (CPIS) on water saving and water productivity compared with Drip Irrigation System (DIS) as microirrigation systems in cabbage production in Rwanda. This research was conducted at the Rwanda Polytechnic/Integrated Polytechnic Regional College Huye (RP/IPRC Huye) farm (2°35′48″ S and 29°44′21″ E, Elevation of 1769 m above sea level), in Huye district of Rwanda. The experimental designed was a Randomized Complete Block Design (RCBD) with three treatments and three replications. The experimental treatments were Clay pot irrigation system, Drip irrigation system, and the control treatment (No irrigation). The soil type was a sand clay loam. The clay pots used were manufactured by mixing clay and sand at the ratio of 4:1 and dried with burning dry grass. Pots were buried under the soil up to their necks, with about 2 cm of their top above the surface of the surrounding. The crop variety used for the study was Zawadi F1 of cabbage produced by the East African Co. Seed, which is adaptable under the agroclimatic conditions of the Huye district of Rwanda. Crop water requirement and irrigation scheduling were estimated by using CROPWAT 8.0 software. Organic manure (20 tons ha^-1) was applied for whole trial during tillage, Nitrogen-Phosphorous-Potassium/ NPK 17-17- 17 (300 kg ha^-1) was uniformly applied around the seedling (ring application) and Urea (300 kg ha^-1) was split applied, first after three weeks of transplanting, and the second application was five weeks after transplanting. The water productivity of CPIS was 36.17 kg m^-3 for DIS was 25.4 kg m^-3, while the control was 31.1 kg m^-3. The results of this research show that CPIS increases water productivity and water saving. Water saved is 40.23% when CPIS is compared with DIS. Clay pot irrigation system can be a viable option for water scarce areas, particularly for small-scale farmers looking to improve their productivity with their small holdings of land in sandy and drier environments.