Abstract
The management that increases yield and reduce excessive amount of water is a priority for agriculture development in arid and semi-arid regions. This research investigated the effectiveness of previously subsurface placement (25 cm) of the clay deposits and drip irrigation on tomato yield, water use efficiency (WUE), soil moisture and salt distribution in the root zone. A calcareous sandy soil had a subsurface amendments and surface and subsurface drip irrigation applied for one year and planted with squash crop prior to seedling tomato. The field experimental site, and randomization, and consequently location of each treatment, replication was the same for the tomato experiment. The clay deposits were collected from western (Khulays) and central (Dhruma and Rawdat) regions of Saudi Arabia. Surface and subsurface drip irrigation were used at rates ranging from 234 mm (T1) to 564.5 mm (T4). The results clearly reveal that nutrients levels in all the experimental plots were quite variable depending on the amendments type, and rate of application, and the irrigation systems. Results show that tomato fruit yield and WUE were significantly affected by amendments rates and type and also by irrigation amounts and system. The soil moisture contents of subsurface drip irrigated layer increased dramatically, while salts accumulated at the surface away from the emitters of subsurface drip irrigation.