EFFECT OF SOIL SURFACE SLOPE AND SOME HYDRAULIC PARAMETERS FOR DRIP IRRIGATION SYSTEM ON GROWTH AND YIELD OF TOMATO

Abstract

A field experiment was conducted in AL-Ramadi desert – Al-Bufaraj region in spring season 2018, North of AL-Ramadi city Far away about 110 km west of Baghdad, aimed to study the influence of the level and slope of the soil and some hydraulic parameters of drip irrigation system on growth and yield of tomato, the texture of soil is Silty loam. The experiment was designed with Split-Split plots according to "RCBD" with three replicates. The experiment included three factors : the first: soil surface(S) at two levels: flat land(S0) and land with slope (S1), the second: Emitter’s discharge (D) with two discharge, emitters type GR, whose discharge 4 Lh-1(D4), and emitters type GR with discharge of 8 Lh-1 (D8), the last factor: lateral line (L), with two lengths, the first length lateral line with a diameter 16mm, 30m (L30) and length 60m (L60). The results of the study showed that the operational pressure 70 KPa is optimal of the operation of the irrigation system, the decrease in leaf area was 7.12%, 3.56%, 3.87% and 10.34% While the percentage of increase in depth roots was 7.50%, 7.14%, 4.55% and 4.17%, but the decrease in the early yield was 6.58%, 23.57%, 20.72% and 29.35%, while the results showed decreased values of total yield, 6.72%,9.85%, 9.71% and 20.10% due to change of soil surface state from flat to slope and increased emitters' discharge and lateral lines, respectively.