Moisture Dynamics and Water Use Efficiency as Influenced by Different Methods and Levels of Irrigation for Vegetable Crop under Salt-affected Soils

The study was conducted at the Agricultural Research Station, Gangavati, University of Agricultural Sciences, Gangavathi in northern Karnataka, India during Rabi/summer, 2007-08 and 2008-09 with beetischolar_main (Beta vulgaris) as the test crop. Under the drip irrigation, the soil moisture content was the highest and maintained almost steadily near the field capacity throughout the cropping period at all distances away from the dripper. The maximum moisture content near the dripper was reduced to the extent of 15 and 19 per cent at a distance of 60 cm away horizontally and vertically downwards, respectively, from the dripper during 2007-08 in case of drip irrigation at 0.6 ET in salinity level-I, against16 and 20 per cent during 2008-09. The soil moisture content at particular distance from the point of application increased with increase in depth of applied water and it decreased with distance from the point of application (R2= 0.83 to 0.92). The maximum water use efficiency of 6.74 and 6.23 kg m-3 was achieved in drip irrigation at 0.6 ET under salinity level-I and the lowest water use efficiency of 2.78 and 2.40 kg m-3 was recorded in drip irrigation at 1.4 ETin salinity level-III during 2007-08 and 2008-09, respectively. Among the surface irrigation levels, the highest water use efficiency of 4.25 kg m-3 at 1.0 ET and 3.32 kg m-3 in 0.8 ET was recorded in salinity level-I during 2007-08 and 2008-09, respectively.