scholarly journals Assessing the Climate Change Impacts on Grain Sorghum Yield and Irrigation Water Use under Full and Deficit Irrigation Strategies

2020 ◽  
Vol 63 (1) ◽  
pp. 81-94 ◽  
Author(s):  
Kritika Kothari ◽  
Srinivasulu Ale ◽  
James P. Bordovsky ◽  
Clyde L. Munster
Keyword(s):  
Climate Change ◽  
Water Use ◽  
Irrigation Water ◽  
Deficit Irrigation ◽  
Climate Change Impacts ◽  
Grain Filling ◽  
Growing Season ◽  
Grain Sorghum ◽  
Full Irrigation ◽  
Irrigation Water Use

HighlightsIrrigated grain sorghum yield and irrigation water use decreased under climate change.Increase in growing season temperature beyond 26°C resulted in a sharp decline in grain sorghum yield.Irrigating during early reproductive stages resulted in the most efficient use of limited water.Irrigating to replenish soil water to 80% of field capacity was found suitable for both current and future climates. Groundwater overdraft from the Ogallala Aquifer for irrigation use and anticipated climate change impacts pose major threats to the sustainability of agriculture in the Texas High Plains (THP) region. In this study, the DSSAT-CSM-CERES-Sorghum model was used to simulate climate change impacts on grain sorghum production under full and deficit irrigation strategies and suggest optimal deficit irrigation strategies. Two irrigation strategies were designed based on (1) crop growth stage and (2) soil water deficit. For the first strategy, seven deficit irrigation scenarios and one full irrigation scenario were simulated: three scenarios with a single 100 mm irrigation scheduled between panicle initiation and boot (T1), between boot and early grain filling (T2), and between early and late grain filling (T3) growth stages; three 200 mm irrigation treatments with combinations of T1 and T2 (T4), T1 and T3 (T5), and T2 and T3 (T6); one 300 mm irrigation scenario (T7) that was a combination of T1, T2, and T3; and a full irrigation scenario (T8) in which irrigation was applied throughout the growing season to maintain at least 50% of plant-available water in the top 30 cm soil profile. For the second strategy, the irrigation schedule obtained from auto-irrigation (T8) was mimicked to create a full irrigation scenario (I100) and six deficit irrigation scenarios. In the deficit irrigation scenarios, water was applied on the same dates as scenario I100; however, the irrigation amounts of scenario I100 were reduced by 10%, 20%, 30%, 40%, 50%, and 60% to create deficit irrigation scenarios I90, I80, I70, I60, I50, and I40, respectively. Projected climate forcings were drawn from nine global climate models (GCMs) and two representative concentration pathways (RCP 4.5 and RCP 8.5). Climate change analysis indicated that grain sorghum yield under full irrigation was expected to be reduced by 5% by mid-century (2036 to 2065) and by 15% by late-century (2066 to 2095) under RCP 8.5 compared to the baseline period (1976 to 2005). Simulated future irrigation water demand of grain sorghum was reduced due to the shorter growing season and improved dry matter- and yield-transpiration productivity, likely due to CO2 fertilization. Based on the simulated grain sorghum yield and irrigation water use efficiency, the most efficient use of limited irrigation was achieved by applying irrigation during the early reproductive stages of grain sorghum (panicle initiation through early grain filling). A 20% deficit irrigation scenario was found to be optimal for current and future conditions because it was more water use efficient than full irrigation with a minor yield reduction of <11%. In summary, these results indicated that strategic planning of when and how much to irrigate could help in getting the most out of limited irrigation. Keywords: CERES-Sorghum, Critical growth stages, Crop yield, Global climate model, Irrigation demand, Soil water depletion.

scholarly journals Determining Optimum Irrigation Termination Periods for Cotton Production in the Texas High Plains

2020 ◽  
Vol 63 (1) ◽  
pp. 105-115
Author(s):  
Srinivasulu Ale ◽  
Nina Omani ◽  
Sushil K. Himanshu ◽  
James P. Bordovsky ◽  
Kelly R. Thorp ◽  
...  
Keyword(s):  
Water Use ◽  
Irrigation Water ◽  
Deficit Irrigation ◽  
Cotton Yield ◽  
Full Irrigation ◽  
Cotton Production ◽  
Seed Cotton ◽  
Irrigation Water Use Efficiency ◽  
Irrigation Water Use ◽  
Use Efficiency

HighlightsIrrigation water use efficiency was consistently higher under deficit irrigation as compared to full irrigation.Irrigation water use was always less than the annual allowable pumping limit under deficit irrigation.The first/second week of September was ideal for terminating irrigation under full/deficit irrigation in normal years.Ideal irrigation termination periods in wet/dry years were a week earlier/later than those in normal years.Abstract. Cotton ( L.) production in the Texas High Plains (THP) region relies heavily on irrigation with groundwater from the underlying Ogallala Aquifer. However, rapidly declining groundwater levels in the aquifer and increasing pumping costs pose challenges for sustainability of irrigated cotton production in this region. Adoption of efficient irrigation strategies, such as terminating irrigation at an appropriate time in the growing season, could enable producers to increase irrigation water use efficiency (IWUE) while maintaining desired yield goals. The objective of this study was to determine optimum irrigation termination periods for cotton production in the THP under full and deficit irrigation conditions using the Decision Support System for Agrotechnology Transfer (DSSAT) CROPGRO-Cotton model, which was evaluated in a prior study in the THP using measured data from an IWUE field experiment at Halfway, Texas. The treatment factors in the field experiment included irrigation capacities of 0 mm d-1 (low, L), 3.2 mm d-1 (medium, M), and 6.4 mm d-1 (high, H), applied during the vegetative, reproductive, and maturation growth stages. This study focused on a full irrigation (HHH) treatment and three deficit irrigation (LMH, LHM, and LMM) treatments. Eight irrigation termination dates with a one-week interval between 15 August and 30 September were simulated, and the impact of irrigation termination date on cotton IWUE and seed cotton yield were studied by dividing the 39-year (1978 to 2016) simulation period into dry, normal, and wet years based on the precipitation received from 1 April to the simulated irrigation termination date. Results indicated that the simulated IWUE was consistently higher under the LHM, LMH, and LMM treatments when compared to the HHH treatment. Based on the simulated average seed cotton yield and IWUE, optimum irrigation termination periods for cotton were found to be the first week of September (about 118 days after planting, DAP) for the HHH and LMH treatments and the second week of September (125 DAP) for the LHM and LMM treatments in normal years. In wet years, optimum irrigation termination periods were a week earlier than those in normal years and a week later in dry years for the HHH, LHM, and LMM treatments. For the LMH treatment, the optimum irrigation termination period in wet years was the same as that in normal years and two weeks later in dry years. The results from this study along with field-specific, late-season information will assist THP cotton producers in making appropriate irrigation termination decisions for improving economic productivity of the Ogallala Aquifer and thereby ensuring water security for agriculture. However, the recommendations from this study should be used with caution, as the optimum irrigation termination periods could potentially change with changes in cultivar characteristics, soil type, climate, and, crop management practices. Keywords: CROPGRO-Cotton, Deficit irrigation, DSSAT, Full irrigation, Irrigation water use efficiency, Seed cotton yield.

scholarly journals Effects of Deficit Irrigation on Yield and Quality of Onion Crop

2016 ◽  
Vol 8 (3) ◽  
pp. 112 ◽  
Author(s):  
David K. Rop ◽  
Emmanuel C. Kipkorir ◽  
John K. Taragon
Keyword(s):  
Water Stress ◽  
Water Use ◽  
Irrigation Water ◽  
Deficit Irrigation ◽  
Water Productivity ◽  
Growth Stages ◽  
Irrigation Water Use Efficiency ◽  
Yield And Quality ◽  
Irrigation Water Use ◽  
Use Efficiency

<p>The broad objective of this study was to test Deficit Irrigation (DI) as an appropriate irrigation management strategy to improve crop water productivity and give optimum onion crop yield. A field trial was conducted with drip irrigation system of six irrigation treatments replicated three times in a randomized complete block design. The crop was subjected to six water stress levels 100% ETc (T100), 90% ETc (T90), 80% ETc (T80), 70% ETc (T70), 60% ETc (T60) and 50% ETc (T50) at vegetative and late season growth stages. The onion yield and quality based on physical characteristics and irrigation water use efficiency were determined. The results indicated that the variation in yield ranged from 34.4 ton/ha to 18.9 ton/ha and the bulb size ranged from 64 mm to 35 mm in diameter for T100 and T50 respectively. Irrigation water use efficiency values decreased with increasing water application level with the highest of 16.2 kg/ha/mm at T50, and the lowest being13.1 kg/ha/mm at T100. It was concluded that DI at vegetative and late growth stages influence yields in a positive linear trend with increasing quantity of irrigation water and decreasing water stress reaching optimum yield of 32.0 ton/ha at 20% water stress (T80) thereby saving 10.7% irrigation water. Onion bulb production at this level optimizes water productivity without significantly affecting yields. DI influenced the size and size distribution of fresh onion bulbs, with low size variation of the fresh bulbs at T80.</p>

Effect of Regulated Deficit Irrigation on Water Use and Economic Benefit of Processing Tomato (Solanum lycopersicum) in an Arid Environment

2014 ◽  
Vol 926-930 ◽  
pp. 4234-4237
Author(s):  
Heng Jia Zhang ◽  
Ai Cun Wen ◽  
Ji Dong Zhang
Keyword(s):  
Water Use ◽  
Irrigation Water ◽  
Deficit Irrigation ◽  
Economic Benefit ◽  
Arid Environment ◽  
Full Irrigation ◽  
Regulated Deficit Irrigation ◽  
Water Deficits ◽  
Processing Tomato ◽  
Irrigated Crops

An experiment was conducted to determine the effect of regulated deficit irrigation (RDI) on water use and economic benefit of processing tomato in an arid environment. The results indicated that seasonal total irrigation water applied to processing tomato was significantly (p<0.05) saved by 14.3% to 42.9% under RDI compared to full irrigation. The irrigation water use efficiency (IWUE) of processing tomato was significantly improved with 32.4% and 57.2% in RDI plots respectively subjected to high and low water deficits at seedling as well as 26.1% in RDI plots subjected to low deficit at late fruiting compared with full irrigation, but no difference (p>0.05) occurred between fully irrigated crops and RDI plants subjected to water deficits at full fruiting as well as low deficit at late fruiting. However, in comparison with fully irrigated crops IWUE was significantly reduced with 20.5% and 22.2% in RDI plants both subjected to water deficits at flowering. Compared to full irrigation, the net income was significantly reduced with 11.3% to 45.3% in RDI plots except that subjected to low water deficit at seedling. Therefore, low water deficit RDI at seedling while full irrigation during flowering to late fruiting could be used to effectively reduce irrigation water application and improve IWUE of processing tomato without causing economic benefit reduction in arid areas.

Optimizing mungbean productivity and irrigation water use efficiency through the use of low water- consumption during plant growth stages

2017 ◽  
Vol 40 (04) ◽  
Author(s):  
Fathy S. El-Nakhlawy ◽  
Saleh M. Ismail ◽  
Jalal M. Basahi
Keyword(s):  
Saudi Arabia ◽  
Water Stress ◽  
Water Use Efficiency ◽  
Water Use ◽  
Water Consumption ◽  
Irrigation Water ◽  
Full Irrigation ◽  
Irrigation Water Use Efficiency ◽  
Irrigation Water Use ◽  
Use Efficiency

This research was conducted during 2014/2015 and 2015/2016 seasonsin the Agricultural Research Station, King Abdulaziz University at Hada Al-Sham region, Saudi Arabia to produce mungbean as a new legume crop in Saudi Arabia using low water consumption through maximizing crop yield with optimizing irrigation water use efficiency under drought stress during vegetative and flowering growth stages.No significant differences were found between the yield and yield components when practicing water stress during vegetative stage compared with full irrigation treatment in the two seasons. MN96 cv. was significantly dominated over NMf cv. in all studied traits except flowering date.The highest IWUE and seed yield/ha were obtained from the MN96 cv. under full irrigation and water stress during vegetative stage without significantly differences between them in the two seasons.

Sign in / Sign up

Export Citation Format

Share Document