Cumin is one of the important spice crops grown in arid and semi arid regions of India and is being adopted to cure some of the dreaded diseases. Determination of optimum water requirement which is function of soil crop and atmosphere is needed for achieving more profit and higher productivity per unit of water. Keeping in view, a field experiment was undertaken to access the conjugate impact of three irrigation regimes (0.6IW/ETc, 0.8IW/ETc and1.0IW/ETc) and three lateral spacing (0.60m, 0.70m and 0.80m) on productivity of cumin. Split plot design with three treatment replications was adopted. Drip irrigation with 0.8 IW/ETc resulted higher seed yield, plant height and dry matter of 1344.17 kg/ha, 36.42 cm and 2365 kg/ha respectively at 0.8 IW/ETc with lateral spacing 0.6 m as compared to other treatments. Highest water use efficiency (5.58 kg/ha.mm) was observed at 0.6 IW/ETc with 0.60 m lateral spacing. Highest B:C ratio (2.27) observed at 0.8 IW/ETcwith lateral spacing 0.6m as compared to other treatments.

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Estimation of runoff in a watershed is a prerequisite for design of hydraulic structures, reservoir operation and for soil erosion control measures. Water resource planning and management is important and critical issue in arid and semi-arid regions. Runoff from a watershed affected by several geo-morphological parameters and for a particular watershed land use change can affect the runoff volume and runoff rate significantly. Several methods are investigated to estimate the surface runoff from a catchment but the Curve Number method is mostly used. Present study was undertaken to estimate surface runoff and water availability for two sites (Ozat-2 and Zanzesri) in the Ozat catchment situated in Junagadh, Gujarat, India using RS and GIS based curve number method. The Weight curve number for the ozat catchment is 73.00. The correlation coefficient between calculated and observed runoff was good for both catchments. In this study found that SCS-curve number method along with RS and GIS can be used successfully in semi-arid region to simulate rainfall runoff and to estimate total surface water.

Reduced cost of cultivation (30%) and increase in yield (40%) obliged the Saurashatra farmers to adopt Bt. Cotton on mass scale. Saurashtra cotton earns more profit at international market due to good luster, low naps, more wax on fibers surface, very low dye absorption. High evaporative conditions, scarcity of groundwater, and deficient rainfall condition are detrimental to cotton yields. Climatic change is adding another dimension to this complex nexus of soil-water-plant-atmosphere. Adverse environmental conditions coupled with water scarcity intrigued farmers of this region to adopt drip irrigation with mulch in Bt. Cotton for mitigating the impact of climatic aberrations. Determination of actual crop evapotranspiration during crop growing season is highly advantageous for sound irrigation scheduling. So far no study is reported to develop crop coefficient for drip irrigated biodegradable mulch cotton subjected to variable irrigation regimes. An experiment was undertaken consecutively for two years (2013-14 and 2014-15) to address this issue. Diurnal and temporal variation of soil moisture with depth was monitored using soil moisture sensors at irrigation regimes 1.0 IW/ETc and 0.8 IW/ETc. The control treatment was taken as drip with no mulch. Adjusted FAO K c predict higher value than sensor based K c values at both irrigation regimes. Sensor based K c-mid values were lower by 12.99% and 30.04% than the adjusted FAO K c-mid value at 1.0 IW/ET c and 0.8 IW/ET c respectively. Biodegradable plastic mulch reduced K c-ini value by 72.26% and 66.54% over control at 1.0 IW/ET c and 0.8 IW/ET c respectively. Overestimated adjusted FAO K c values caused a loss of 78.13mm and 66.54mm of precious water at 1.0 IW/ET c and 0.8 IW/ET c respectively. This study admonishes blind adoption of published FAO K c curves, for mulch conditions.

In the era of decreasing irrigation water availabilities, the focus must be on decreasing crop production water footprints. The various irrigation water management like deficit irrigation, fertigation, and mulching along with MIS can help reduce water footprints. However, the effects of aerated drip irrigation on sweet corn performance under various options of irrigation water management are not yet examined elsewhere. So, it was assessed through field experiments for 2 years during the winter season of the year 2020-21 and 2021-22 at the research farm of the Junagadh Agricultural University campus at Junagadh having a soil texture of clay loam. Two air injection rates i.e. 0 and 12 % by volume of irrigation flow rate was imposed on 16 different treatment combinations of 2 irrigation levels (deficit irrigation-0.7 ETc and full irrigation-1.0 ETc {Crop Evapotranspiration}), 2 fertigation levels (deficit fertigation-0.7 RDF and full fertigation-1.0 RDF {Recommended Dose of Fertilizer}), 2 drip system type (surface drip and subsurface drip) and 2 mulch levels (mulch and no mulch). The aerated irrigation effects on the production of fresh cob yield were found different under various options of irrigation water management. Overall, on average, sweet corn cob yield increased by 8.94% due to aerated irrigation as compared to non-aerated and the results were found significant. The adoption of aerated subsurface drip irrigation under mulch with irrigation/fertigation scheduling at 1.0 ETc/1.0 RDF would result in higher yield if adopted by farmers, in other words, the yield increase of fresh cob would be almost twice as compared to traditional practices with benefit cost ratio (B/C) as 3.01 for aerated treatment and 2.78 for non-aerated treatment for subsurface drip irrigation under mulch with irrigation/fertigation scheduling at 1.0 ETc/1.0 RDF.