Effect of Black Polyethylene Mulch on Quantity of Tomato and Water Use Effeciency

Polyethylene mulch usually decreases water evaporation from soil surface، control weeds and increase yield crops. In order to study the effects of black mulch on tomato yield، yield components and water consumption efficiency an experiment was conducted in Kahriz Station (Urumia، Iran) for two years (2005-2007). The experiment was carried out at split plot factorial in CBR design with four replication in a loamy silt soil. Experimental treatments were row spacing (100 and 120 cm)، in-row spacing (30 and 40 cm) and black plastic. The treatments of black plastic were: full ridge and half furrow were covered by mulch; full furrow and half ridge were covered by mulch and control (no mulch) respectively. Each plot was irrigated separately. The results indicated that mulch was effective on yield and yield ingredients (weight fruit and fruits number per plant) and interaction on yield ingredients at 1%. The best treatment of mulch for yield increase، earliness and weed control was full ridge and half furrow. Interaction of plant density and mulch affected only earliness and stem length. Water use effeciency (WUE) was increased by using mulch. Water decreased 28. 8 % and 41. 3 % in full ridge and half furrow and full furrow and half ridge respectively in comparison with control. The best treatment according on WUE was full furrow and half ridge covered by mulch and 100×30 sowing pattern with 33 kg. m3.