Comparative water budgeting and water use efficiency of irrigated lowland rice under drum culture and AWD-based drum culture techniques in semi-arid tropics of Telangana, India

Evaluation of water balance components through drum culture technique during kharif seasons of 2019 and 2020 was conducted in the clay soils of RARS, Polasa, Jagtial, PJTAU, Hyderabad, Telangana, India. Water balance components were measured through drums on a loss and gain basis using a measuring scale twice daily. Quantification revealed maximum water use efficiency and yield under AWD based drum culture technique than transplanted rice with drum culture technique alone. The study quantified evapotranspiration (ET), evaporation, percolation, seepage, and effective rainfall. AWD significantly reduced percolation and improved irrigation water use efficiency (IWUE) without a yield penalty, showing potential for sustainable rice production in semi-arid tropics. However, challenges such as labor-intensive monitoring of water levels, variability in soil hydraulic properties, dependence on timely rainfall, and the need for farmer training on AWD thresholds were observed, which may limit widespread field adoption. Addressing these constraints is essential for wider field-scale adoption.
Water scarcity has become one of the major constraints to sustainable rice production, necessitating the adoption of efficient irrigation management practices. This experiment to evaluate the effect of alternate wetting and drying (AWD)-based drum culture on seasonal water budgeting, irrigation water productivity, and grain yield of transplanted rice compared with conventional puddled transplanted rice (PTR). The experiment comprised two treatments: T₀ – conventional transplanted rice with drum culture technique and T₁ – transplanted rice with optimum water management using AWD through drum culture.
AWD substantially reduced seasonal water losses by lowering mean evapotranspiration from 429.0 to 351.2 mm, evaporation from 425.0 to 266.2 mm, and percolation from 511.0 to 289.3 mm. Mean irrigation water application decreased from 998.5 mm under conventional transplanting to 698.5 mm under AWD, resulting in approximately 30% irrigation water saving. Effective rainfall utilization increased, while ineffective rainfall losses were markedly reduced under AWD.
The total irrigation water applied, including nursery and puddling water, averaged 1239 mm under conventional transplanting and 938.5 mm under AWD. Irrigation water-use efficiency (IWUE) improved from 3.37 to 5.45 kg ha⁻¹ mm⁻¹. In the main field, irrigation water application decreased from 796 to 300 mm, while IWUE increased from 4.26 to 13.00 kg ha⁻¹ mm⁻¹ and field water-use efficiency (FWUE) increased from 3.23 to 6.01 kg ha⁻¹ mm⁻¹. AWD also enhanced crop performance by increasing tiller number, panicle density, filled grains per panicle, and grain yield. The pooled mean grain yield increased from 4258 kg ha⁻¹ under conventional transplanting to 5149 kg ha⁻¹ under AWD, representing an increase of approximately 20.9%. The study demonstrates that AWD-based drum culture is an efficient irrigation management strategy that conserves irrigation water while improving water productivity and rice yield. Adoption of AWD can therefore contribute to sustainable rice cultivation, particularly in regions experiencing increasing water scarcity.