Among different irrigation methods used for cultivation of seed spices in arid areas, cumin shows the better performance with sprinkler irrigation as it warrants the sensible water utilization and savings (Malhotra et al.,
2009). Sprinkler irrigation further plays a significant role in increasing yield as well as quality of the produce by ensuring the proper and uniform germination of crops (Ravindran et al.,
2006). Deficit irrigation offers another valuable tool to deal with the problems of restricted water availability in arid areas. It is revealed from the literature that deficit irrigation saves water quantities and improves water productivity of cereals and other crops in arid climate (Kumar et al.,
2019; Attia et al.,
2021; Kheir et al.,
2021; Meena et al.,
2021a,
b,
2025; Rathore et al.,
2021). However, few studies have investigated cases in which deficit irrigation is adopted to improve water productivity of seed spice crops, particularly cumin. Bondok and El-Sharkawy (
2014) compared amount of irrigation water, yield, and yield components of cumin under surface irrigation and sprinkler irrigation at deficit and full irrigation levels (60.0%, 80.0%, and 100.0% actual crop evapotranspiration (ET
c)) in El Gharbeia Governorate, Egypt. Results revealed about 45.5%-47.9% water savings through sprinkler irrigation with 10.2%-12.5% increment in cumin yield. Furthermore, yield showed 14.2% and 26.2% decreases and water productivity showed 6.9% and 14.9% increases under deficit irrigation at 80.0% and 60.0% actual ET
c, respectively, over the full irrigation (100.0% actual ET
c). Ozer et al. (
2020) imposed different deficit irrigation treatments to black cumin (
Nigella sativa L.) in Turkey based on cumulative pan evaporation (CPE) approach. The results indicated yield reductions of 13.5%, 18.9%, and 30.1% at deficit irrigation levels of 80.0%, 60.0%, and 40.0% CPE, respectively, as compared to the yield (1413.50 kg/hm
2) obtained under full irrigation (100.0% CPE). However, irrigation water use efficiency achieved under full irrigation was 6.2%, 23.0%, and 37.6% lower than that obtained under deficit irrigation at 80.0%, 60.0%, and 40.0% CPE, respectively. Mehta et al. (
2014) irrigated cumin at three intervals, i.e., 12, 15, and 18 d by employing flooding method. The maximum cumin yield (471.00 kg/hm
2) was obtained at the 18-d interval as compared to 12- and 15-d intervals. Besides, water productivity at the 18-d interval was also found higher (0.236 kg/m
3) than that at 12-d (0.074 kg/m
3) and 15-d (0.139 kg/m
3) intervals. Rao et al. (
2010) reported that the maximum yield (677.50 kg/hm
2) and water productivity (0.311 kg/m
3) were obtained for cumin irrigated through micro-sprinklers at irrigation water/cumulative pan evaporation (IW/CPE) of 0.8 as compared to that at IW/CPE of 1.0, 0.6, and 0.4. Jangir et al. (
2007) reported that the water productivity for sprinkler-irrigated cumin having five irrigations was 0.260 kg/m
3, and the crop yield was 411.00 kg/hm
2. In a semi-arid area of India, adoption of drip and micro-sprinkler for irrigating cumin crop saved water quantities by 68.5% and 58.1%, respectively, over the flood irrigation (Singh et al.,
2015). Also, drip irrigation (cumin yield of 319.50 kg/hm
2) and micro-sprinkler irrigation (cumin yield of 314.85 kg/hm
2) improved the water productivity by 4.74% and 4.29%, respectively, over the flood irrigation (cumin yield of 186.45 kg/hm
2 and water productivity of 0.721 kg/m
3). Kunapara et al. (
2016) evaluated the effect of three deficit irrigation levels (i.e., IW/ET
c of 0.6, 0.8, and 1.0) on cumin yield and water productivity in Junagarh, India. The results indicated the maximum crop yield (1255.78 kg/hm
2) under deficit irrigation at IW/ET
c of 0.8 as compared to that at IW/ET
c of 1.0 (1042.83 kg/hm
2) and 0.6 (1098.67 kg/hm
2), whereas water productivity was found to be the maximum under deficit irrigation at IW/ET
c of 0.6 (0.555 kg/m
3), followed by the IW/ET
c of 0.8 and 1.0 (0.476 and 0.316 kg/m
3, respectively). Lal Mehriya et al. (
2020) evaluated yield and water productivity under three irrigation levels, i.e., 40.0%, 60.0%, 80.0% CPE for drip-irrigated cumin and 80.0% CPE for flood-irrigated cumin. The maximum crop yield obtained at 80.0% CPE (1066.67 kg/hm
2) under drip irrigation was higher as compared to that obtained at 60.0% CPE (1062.67 kg/hm
2) and 40.0% CPE (934.67 kg/hm
2) under drip irrigation and at 80.0% CPE (631.00 kg/hm
2) under flood irrigation. The drip irrigation at 40.0% CPE resulted in the maximum water productivity (0.570 kg/m
3) and water saving (39.0%), followed by 60.0% CPE (water productivity of 0.480 kg/m
3 and water saving of 18.9%).