Agricultural Research Journal

Measurement of water productivity/use efficiency is an important tool for the selection of soil and crop management technologies for enhancing yield as well as irrigating water savings In the present study quantitative information is synthesized from the data at hand in the literature on change in water productivity, based on irrigation water (WP_I), total water (irrigation rain) input (WP_I+R) and evapotranspiration (WP_ET), corresponding to change in yield, irrigation water, and evapotranspiration (ET) in different soil, water and crop management technologies. WP_I and WP_ET are more in the technology which ensures a more % increase in yield than a % reduction in irrigation water and/ or ET. WP_ET is increased with increasing transpiration (T) component of ET and subsequently yield by means of mulching with crop residue, deep tillage, and N application. WP_I is increased with a reduction in irrigation water via (i) growing shorter duration cultivars in the period of least potential evaporative demand in which yield potential is highest (ii) scheduling irrigation based on the demand and using proper irrigation method (iii) modifying soil surface in such a way that irrigation is applied in shorter period (with laser leveling) and applied water retained is more and for longer period by the soil (medium to finer textured soils). Amongst different crops, WP_I is more in sugarcane and less in rice while WP_ET is more in sugarcane and less in cotton. In a cropping system, WP_ET is less as ET is more due to its inclusion from intervening bare period too.