Analysis of soybean yield formation differences across different production regions in China

Understanding the yield gaps and its limiting factors under different soybean [Glycine max(L.) Merr.] production environments is essential in order to increase yield to meet plant‐based protein and vegetable oil requirements. Soybean yield data from the National Crop Varieties Test (NCVT) were analyzed to identify yield‐limiting factors and yield improvement measures in the four soybean agro‐ecological regions in China. The average yield was 2.70 Mg ha−1, with a unimodal distribution from North to South. The highest yield was in Huang‐Huai‐Hai Plain (HHH), followed by Yangtze River Valley (YRV), Northeast (NE), and Tropical and Subtropical region (TS). Seed weight was a major limiting factor of yield improvement for low‐yield farmfields, while pods per plant and seeds per plant were both limiting factors of yield improvement for middle‐ and high‐yield farmfields. Choosing improved soybean varieties in the right areas is the most critical factor in increasing yields. Selecting high‐yield soybean varieties with high seed weights should be the primary task to further improve the yield for NE region. Increasing seed number and seed weight by preventing pod shedding and abortion with chemical control techniques from flowering to pod formation should be the key yield‐increasing measures for soybean production in YRV and TS regions. Furthermore, attention should be paid to maintaining soil moisture and ensuring water supply in HHH region. Furthermore, advanced agronomic techniques, such as high‐precision sowing, proper plant protection controls, and proper fertilizer formulas based on soil testing, are also vital measures to improve soybean yields.