Fertilizer and irrigation effects on forage protein and energy production under semi-arid conditions of Pakistan

• Two cropping systems (common and drought adopted) were compared for fertilizer and irrigation effects on forage quality.
• Irrigation water use efficiencies for crude protein (CP) and metabolizeable energy (ME) were also studied.
• Fertilizer and irrigation did not affect the quality parameters significantly.
• Drought adopted system proved more water efficient for CP and ME production.
• Nutritional quality of both systems was in acceptable range.

Fertilizer and irrigation water are major inputs for forage production in semi-arid areas, and to ensure sustainability, nutrient and water efficient crop species should be used. The major objectives of the present study were to (i) evaluate the effect of crop species, fertilizer and irrigation on nutritive value and (ii) determine irrigation water use efficiency (IWUE) in terms of crude protein (CP) and metabolizeable energy (ME) production per unit of land. A two-year field experiment was conducted in Faisalabad, Pakistan, with a four times replicated completely randomized design in a split-plot arrangement of a combination of fertilizer treatment (control, farm yard manure (FYM) and mineral fertilizer (MIN)) and irrigation (recommended irrigation (RI), half recommended irrigation (HRI)) as main-plots. Sub-plots were assigned to two cropping systems Egyptian clover (Trifolium alexandrinum L.) followed by corn (Zea mays L.) (common cropping system, CCS) and the drought-adopted cropping system (DACS) oat (Avena sativa L.) followed by sudangrass (Andropogon sorghum subsp. drummondii). Crude protein concentration and IWUE of CP production per unit of land in CCS was 44 and 13% higher than in DACS, whereas ME contents and IWUE of ME production in DACS was 9.5 and 38% higher than in CCS. In view of ME as the major limiting nutritive property in roughages for feeding dairy cows, it is concluded that the tested DACS may be more suitable for sustainable forage production under water and nutrient limited conditions in semi-arid areas of Pakistan.