Addressing wheat yield gaps

Cultivation of wheat using raised-bed planting

With financial support from the Russian Federation, ICARDA analyzed 18 sites in Central Asia - encompassing the full range of agro-ecological zones - to determine how to address the gap between the area's potential wheat yield and its low productivity.

Despite the large growth potential in agriculture characterized by high crop diversity and farming traditions, productivity in Central Asia is low. A variety of reasons explain the latter: land erosion; over-grazing; over-irrigation leading to increased soil salinity; increasing global climate change effects that exacerbate droughts, frosts, and high temperatures; and poor land management. Closing the yield gap is key to addressing regional food and economic insecurity.

Throughout 18 sites of CA — in Kazakhstan, Kyrgyzstan, Tajikistan, and Uzbekistan — crop growth parameters and actual yields in farmer and experimental fields were collected. CROPSYST modeling analysis for each of these 18 sites identified potential interventions for the best use of a location’s agro-ecological characteristics to achieve highest yields:

  • In the case of early sowing, pre-sowing irrigation and nitrogen-level management interventions would be applied to the rain-fed (spring) wheat production in Kazakhstan and Tajikistan — CROPSYST model results demonstrated an increase of 158% in farmers’ harvests while the experimental stations’ performance improvement ranged from 16% to 110%.
  • In irrigated sites, salinity management, optimum irrigation and nitrogen management could potentially increase farmers’ yields from 36 to 182% under model-based interventions, with experimental station yields potentially improving by 5 to 47%.

As water scarcity is an ongoing reality in the region, the analysis also determined that targeted crop breeding, crop rotation with alfalfa, irrigation and nitrogen management, and improved seed varieties that are drought and heat resistant could further lower the yield gap.