563practice under SI; therefore, knowledge of water stress-sensitive growth stages
concerning the timing of water application is critical.4 Conclusions
Supplemental irrigation is a promising practice to overcome the climate change-
induced challenges of low and erratic rainfall and to enable earlier planting. Here,
we have presented case studies covering different drylands of the WANA region as
well as different commodities to argue that supplemental irrigation brings more
benefits than the cost involved in implementing the practice. However, the practice
is not suitable for all rainfed situations, and care must be taken when adopting or
promoting it. A sustainable source of freshwater, as well as appreciation for down-
stream users of water, is a must before adopting this practice. If there is scope for
harvesting excess runoff, use groundwater or other blue water sources, the practice
should be adopted to bring resilience from erratic climatic conditions as well as to
provide a critical dose of irrigation to substantially increase yields and water
productivity.
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Supplemental Irrigation: A Promising Climate-Resilience Practice for Sustainable...