Potential for Crop Production Increase in Argentina through Closure of Existing Yield Gaps.

Argentine crop production has grown significantly during the last twenty years, but it is unclear how much further it can increase. The objectives of this work were i) to quantify the potential for crop production increase in Argentina through closure of existing yield gaps, and ii) to analyze the variation of this gaps among years and regions.

Yield potential (Yp) and water-limited yields (Yw) were estimated for the three Argentinean main crops (i.e. soybean, wheat and maize), using local calibrated crop simulation models embedded in DSSAT v4.5, at 15-16 buffer zones that cover ca. 50% of each crop area, considering local management practices and soil variability. Actual farmer’s yields (Ya) were calculated based on the actual yields reported for the departments located within the buffer zones for the last seven cropping seasons. The yield gaps (Yg) were estimated as the difference between Yw and Ya, because most of Argentine crop area is under rainfed condition. An appropriate upscaling method was used to obtain regional and national estimations.

National Yw were 3.9, 5.3 and 11.6 t ha^-1, Ya were 2.7, 3.1, and 6.8 t ha^-1 and Yg were 1.2, 2.2 and 4.8 t ha^-1 for soybean, wheat and maize respectively. Overall, soybean Yg (31.7%) were smaller than wheat (41.1%) and maize (41.5%) Yg.  High spatial variability was observed, related to cropping history and environmental conditions of each zone. Moreover, El Niño Southern Oscillation phenomenon (ENSO) had a significant effect on summer crops Yw, Ya and Yg.

These estimations are useful to prioritize research and enhance agricultural production through focus on areas with largest unexploited yield gaps and greatest potential to close them through ecological intensification.

This work forms part of the Global Yield Gap Atlas Project (GYGA), and its results are available on www.yieldgap.org.