Agricultural irrigated area depends on the availability of irrigation water. To cope with scarcity of water supplies, deficit irrigation is an important tool to achieve the goal of reducing irrigation water use. Field experiments were carried out to study the effect of forward speed of seed drill (2.1, 3.6, 4.5 and 6.3 km/h), deficit irrigation (zero, 15 and 30%) and fertilization methods (broadcasting and fertigation) on the amount of water applied, productivity, water and fertilizer use efficiency, net return and net return/m3 of Quinoa (Chenopodium quinoa W.) in sandy soils.
The main results of the study could be summarized as follow:-
- Increasing the forward speed, increased field capacity and therefore, seed scattering was increased, vice versa field efficiency values were decreased.
- Amount of water applied and water consumptive use were (1989 and 1611), (1750 and 1407) and (1527 and 1268) m3/fed for treatments zero, 15 and 30% deficit irrigation, respectively. The water saving was 12 and 23.2 % for treatments 15 and 30% deficit irrigation, respectively as compared with treatment zero deficit irrigation.
- Seed and straw productivity, water and fertilizer use efficiency, net return and net return/m3 were increased under using fertigation method and forward speed of 3.6 km/h.
- Net return/m3 under 15% deficit irrigation (2.55 LE/m3) was higher than under zero and 30% deficit irrigation (2.31 and 2.54 LE/m3) under fertigation method and 3.6 km/h forward speed.
- Fertilization by fertigation was more efficiency than broadcasting fertilizers.