Prospects for soybean production increase by closing yield gaps in the Northeast Farming Region, China

Although China is the world's largest soybean consumer, its increasing demand relies heavily on imports from international markets, which restricts national and global food security. Northeast Faring Region (NFR) is one of the most important soybean producing areas in China, accounting for approximately 41% of total national production. To date, information about soybean yield potential and gaps remain unclear in NFR. Herein, we firstly investigated soybean irrigated potential yield (Yp), rainfed potential yield (Yr), potential yield (Ypaw), attainable yield (Yt), actual yield (Ya), and determined yield and production gaps by following the Global Yield Gap Atlas protocol in five subregions in the NFR. After calibration and validation, the CROPGRO model could reasonably simulate soybean growth, development, and yield, and was used to simulate Yp and Yr for 17 reference weather stations within NFR. The regional area-weighted mean Yp, Yr, Ypaw, Yt, and Ya were 4.80 t/ha, 3.51 t/ha, 3.81 t/ha, 2.97 t/ha, and 1.81 t/ha, respectively. The gap between Ypaw and Ya was 2.00 t/ha, indicating local farmers only achieved 48% of Ypaw, while the total production gap was 12.1 MT in 2020. Regional production increase was mainly achieved by closing yield gaps rather than expanding planting area. If yield reaches the Yt level without enlarging planting area, regional production would increase by 60%. The Songliao plain played a vital role in NFR's soybean production and had the largest production gaps among five subregions. Therefore, the subregion should be paid special attention to narrowing production gaps in the coming years. These results could provide valuable insights for developing local policies, improving soybean production, and ensuring food security in China.